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Guru

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Husqvarna's built-in chain brake problem-repair how-to

02/22/2008 12:06 AM

Hello members. This might take several picture postings, so...first pic first. Depicted below is the combination chain-(drive-clutch)-brake/anti-kickback mechanism assembly used on Husquvarna 36, 41 and similar felling-type (as opposed to arborist's') saws. I am hoping this question finds someone who has "been-there-done-that" when it comes to servicing (disassembling, resetting, reassembling) these (specifically, Husqvarna) assemblies; or one of those rare "mechanically minded's" able to "see through" a mechanism's cover; envision what goes on to accomplish the intended (system) function; and "see" how everything goes together according as designed. What you see here is the "Unit" in its assembled condition; however it is not assembled correctly--one interior component at least is out of place, with the result that:

  1. The Unit assy cannot be properly (if at all) fitted back (with binder band) over the chain drive clutch, and attached (along with bar and pictured chain) to the main saw body.
  2. The almost new (about 45-60 min. of use) saw cannot be used.

Now some background and a description of what is the problem. (Continued below picture)

Due to a possible design and/or mfg assembly flaw (or incorrect maintenance instructions in the user's manual could have played a part), when the saw was being operated something happened inside the assy (inside the handle and adjacent cover plate)--some kind of false triggering, slippage, misalignment, ...whatever--which resulted in the binder's (the circular strap's) being retracted to the "brake-on" position. (Presently, the binder is in extended, brake-off configuration; but, as said, the unit is incorrectly assembled...such that the anti-kickback mechanism is not set under tension. (That is to say, the handle should be pivoted fully rearward (not forward as shown) for the binder strap to be opened as shown.)

Now, with the binder strap in the retracted or near-retracted (applied or near-applied) state, the following functional faults come into play:

  • When installed on the saw, the saw can be started but cannot be rev'ed to cutting (top rpm) speed; the centrifugal clutch mechanism that turns with the main drive shaft engages a clutch drum which in turn (being gripped by the binder strap) resists acceleration (increasingly with application of engine torque)...causing the chain, and engine, to stall—just as if the brake had been normally, manually applied to stop and idle the chain—or just as if a kickback had done the same.
  • When not installed, the retracted binder cannot be fit over the clutch drum...hence the saw cannot be assembled for use.
  • If affixed to the saw body (somehow), the unit assembly cannot be detached from the saw (as for normal maintenance service) since the drum will be in the grip of the binder strap; and forcing it off will cause damage.

So what is the problem? The next pic is the blow-up illustration of the chain brake handle assembly from the saw owner's manual.

Below is a better view of the upper rendering, showing the components of the anti-kickback/binder-self-triggering components more clearly. (Unfortunately, due to a poor explosion rendering, neither drawing reasonably depicts how the parts fit together when assembled.) (Continued under pic)

It is the multi-form, multi-directional spring (find 1, pn 530 01 59-01) which, in particular, is causing the problem with reassembly. It seems certain that it must project from a point of pivot (apparently the same as the handle pivot) upward and leftward (ala the drawing) into the the handle support part of the handle assy. However, the drawing does not depict how, and where, the spring (the spring's bitter end at right) engages with the binder-actuation link (pn 501 87 53-01). It is this interface between handle and link which seems to be critical to correct operation (and operability) of the anti-kickback and clutch/de-clutch functioning....

Below is a paste-up illustration showing the approximate orientation of components which ought to have been shown in the mfr's blow-up drawing.

This view shows the link assembly aligned just above its installed position with nipple at right fitted into groove on cover assy at bottom. The subject spring is shown, orphaned. In the pic below can be seen the interfaces (among others) between handle and pivot point on cover assy, and between link assy and link pivot point on handle. (Continued below pic.)

Finally, a few "real life" images to better show how the drawings relate to the actual assemblies.

Pics just above and below are reverse direction from previous subassembly dwg's.

Thank you for your help. And another thing, neither the owner manual nor the manufacturer/seller/or "authorized" service are of any help or use with this problem. The Husqvarna manuals are distinguishable only by the carelessness of their writing and editing (I even rewrote a Husky manual maintenance procedure which could never be done as written--my offer to provide it to the mfr fell on deaf ears. Similarly, this problem with the Husqvarna chain brakes appears to be "over the heads" of Husqvarna U.S. technical support.

Note: some of the illustration were composed using copies on transparencies of the manual depiction. However, I've not been able, due to inherent photocopier distortion, to make a superimposition "mock up" which might give a clue as to where the spring should fit in the overall assembly.

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#1

Re: Husqvarna's built-in chain brake problem-repair how-to

02/22/2008 8:42 AM

Wow! good luck with this one.... i hope someone can help you, I'm afraid I know little about chain saws..

John.

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#2

Re: Husqvarna's built-in chain brake problem-repair how-to

02/22/2008 12:54 PM

I can't help much either. I'm still trying to figure out how to attach the bag to my lawnmower.

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#3

Re: Husqvarna's built-in chain brake problem-repair how-to

02/22/2008 1:14 PM

John, Bruce,

Thanks anyway for looking and...trying(?).

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Commentator

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#4

Re: Husqvarna's built-in chain brake problem-repair how-to

02/22/2008 3:05 PM

Sounds like you have the brake engaged. To disengage it, pull the handle back as far as possible, should click off. I hope it's that easy. Otherwise, they must have the wrong length brake band installed.

I have a Husky 359 felling saw, it has several hundred hours on it, and have never had a problem beyond theusual stuff. the marine construction division at my work uses these saws exclusively, because they are so darn good.

If I misunderstood your problem, please explain, and I'll go chat with one of my mechanics, who works on these very type of saws daily, on monday.

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#5

Re: Husqvarna's built-in chain brake problem-repair how-to

02/22/2008 3:19 PM

Oh yeah, probably the best place on the internet to get a good reply to your onundrum would be the arborsists site: http://www.arboristsite.com/

Good luck.

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#6

Re: Husqvarna's built-in chain brake problem-repair how-to

02/22/2008 4:37 PM

Fierce Allegience,

Yes, it is quite a conundrum (...your most recent post), and, yes, my presentation seems to have created a confusion (...your post before that). So let me clarify how the problem, and my question here, came about.

The first symptom occurred while I was doing some cutting, when, after restarting the saw—perhaps with brake-on, perhaps brake-off, I don't recall...)—the saw started and idled normally. (This is both normal and possible, as the clutch engages by virtue of centrifugal force increase with rev increase; slow rev, no clutch engage.)

Then, as I squeezed to rev the saw for cutting, the chain would not come up to speed, and the engine (also) refused to comply, instead stalling and stopping. A check of all visible, movable parts, and of fuel and lubrication systems indicated nothing amiss. Next, hoping to check the sprocket area for problems, I removed (down to and including) the (sprocket) cover assembly (that assembly also includes the brake handle [with anti-kickback and brake-binder-actuation mechanisms inside]). However, the cover resisted removal, and a closer look...revealed the brake binder strap to be retracted against the clutch drum, resisting removal of cover, of which the binder is an integral part. Since the brake handle was in correct position for cover removal, I attempted to move it to brake-on position and then back, hoping to "dislodge" whatever the "jamb" or misalignment might be. This was to no avail so, figuring the fault must lie inside the brake control/triggering mechanism, I managed to ease the binder free and remove the cover/brake assembly.

Next, and referring to the blow-up drawing above, I disassembled the cover/handle assembly to reveal all the parts shown (both correctly and incorrectly) in the exploded parts illustration. This required some doing because some parts were under spring-loaded tension...but I finally managed to get it totally disassembled...and figure out how it goes back together...except for the spring (as mentioned in original post).

No matter how I tried to position the spring (or figure out its functioning) I was unable to arrive at a reassembled unit that worked (that operating the brake band) as per design. (There is one exception to this last statement: If I removed the helical compression spring from under its cover, then the brake application mechanisms (binder and links to hand grip) could be made to smoothly open and close the binder strap. (Oh yes, not only the compression spring was left out, but also the subject, multi-directional (problem) spring as well. Coincidentally or not, this part [about the two springs] seems to suggest that the two springs some how counteract each other when installed properly in order for manual, brake-on/brake-off actuation to be achievable. But, whether or not this is true, it does not reveal how the problem spring is to be fitted during sprocket cover/brake reassembly.

Now here's the part where the "confusion" comes in. In order to prevent any possible loss of components, I decided to reassemble the assembly (including with miss-fitted spring)...and then store it with the saw in that condition...pending help from somewhere or someone who could advise how the spring must be fitted for the brake to work properly. It is this condition--with brake assembly not disassembled--shown in the above, actual item depictions that has perhaps led the the conclusion I'm asking for help to detach/reattach the cover/brake assy from/to the saw body.

So, to summarize the question at its most basic: I need to know how the funny spring fits together with the rest when (after again disassembling) I put the cover/brake assembly back together. My hope is that either someone knows exactly how on exactly these saw types, or some one smarter than me can figure out the spring's mechanism of function and be able to suggest how it must fit...or how it cannot fit and still have the brake mechanism work.

Fierce, sorry it took a bit of over-verbiage to explain. I pray this has not place you into a conundrum as well. Let me know if any of my explanation is...inexplicable.

CA

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Anonymous Poster
#7
In reply to #6

Re: Husqvarna's built-in chain brake problem-repair how-to

02/23/2008 12:20 AM

Looks like something might be wrong or broken in the cocking mechanism for the chain break. Check the parts inside the gaurd handle.

http://www.reviewcentre.com/review273083.html

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#18
In reply to #7

Re: Husqvarna's built-in chain brake problem-repair how-to

02/23/2008 12:31 PM

# 7, checked the link...and now I'm getting that sinking feeling. There are some things though that some of those on the review centre forum could do to alleviate the problems with the saw. For one, they're not realizing that the saw is fitted with Oregon chipper chain--the chain saw equivalent of dumbing down. This makes the say best serviceable for very light work such as chopping/pruning branches and felling very small trees. That's why the complaints of slow cutting and burning and such. I came across an arborist who knew just how to "adjust" the chain to eliminate the problem--and without having to replace with a more aggressive chain (but that is an option as well.) He simply pulled out his trusty file and gauge (a size smaller that specified for the saw in the manual) and proceeded to resharpen, giving the saw sharp as well as more aggressive cutting edges--making it a true felling chain. After that (until the brake failure) the saw easily zipped through logs small and large, soft and hard, with the best of them. Instead of needing even light pressure, the chain actually pulled the saw bar through the tree as it cut; you only had to hold it in place. (Bye the weigh, as he taught me about sharpening--which he said he learned from an old, Indian logger--he said the best thing is to forget about fancy dremel stones, tools and expensive sharpening contraptions. They will never sharpen as well as someone with file who "knows the art."

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#19
In reply to #18

Re: Husqvarna's built-in chain brake problem-repair how-to

02/23/2008 2:20 PM

I strongly suggest use of the more aggressive chisel tooth chain. Makes for much quicker work, less strain, less heat on the chain and less gas.

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#23
In reply to #6

Re: Husqvarna's built-in chain brake problem-repair how-to

02/23/2008 7:13 PM

Not sure if this will help but it is possible the spring is too strong and not allowing the brake to disengage properly.

I had a similar problem and threw the original spring away and fitted a softer spring it worked fine after that!!

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#46
In reply to #23

Re: Husqvarna's built-in chain brake problem-repair how-to

03/10/2008 8:26 PM

Thank you.

Response: See posting #39.

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#105
In reply to #23

Re: Husqvarna's built-in chain brake problem-repair how-to

06/01/2013 11:56 AM

I have the same problem on my Husky 268. Handle won't move rearward. If I take out the large spring, handle moves forward and backward easily, but now I don't have chain brake! It's the original spring. Did it get more rigid over time? Brake band is now contracted. Cannot slip band over clutch unless I remove the spring and cut without chain brake.......don't feel good doing this.

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#106
In reply to #105

Re: Husqvarna's built-in chain brake problem-repair how-to

06/02/2013 12:25 PM

Jeez this was a long time ago, I have forgotten most of what it was about.

Problems arise with wear and tear steel and plastic do not mix well and things tend to slop around with pivot points and linkages.

The original spring was keeping the brake in the locked position and could not be released by manual manipulation. So a softer spring from my spare parts dept was used and it fixed the problem.

Whatever you do do not use your machine without all safety's fitted.

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#8

Re: Husqvarna's built-in chain brake problem-repair how-to

02/23/2008 2:38 AM

Hello, the way I think the spring triger (530 01 59-10) and the link (501 87 54-01)work togather is when the handle/brake is in the rear position the link is straight compressing the brake spring (501 87 54-01). Then when the handle/brake is forward the link trips like a finger bending releasing the compressing pushing the link (501 87 54-01) back pulling the brake band and stoping the chain drive drum. So the spring triger (530 02 59-10) needs to apply preasure to the link (501 87 54-01) someway to keep the link straight from sagging.

After looking at the pixs again, does the left end of the link fit in the grove of the side panel (530 03 75-47) secured with pin(720 87 54-01) then the metal spring(501 87 47-01)sit over the left end of the link sticking up? If so then the spring (530 01 59-10) should sit under the link (501 87 53-01) lifting it up. Then the pin(501 87 49-01) rides on top of the link(501 87 53-01) like cam and lobe. When the handel/brake is back it pulls/pushes back on the lever arm of the link, compressing the spring(501 87 54-01) releasing the break band. Then the metal spring(501 87 54-01) notch holds the handle in place ready to trip.

The way I proably would assy it would leave pin(501 87 49-01)out until everything is togather then looking through the hole, move the handel till the lever is left of the hole or till the pin will sit on top of the lever.That position should be in the triped position handle/brake fowared insert pin (501 87 49-01) then clip it.

Then try handle/brake the band should release when pulled back.

I hope this helps, the brake assy looks a lot like what's on my poulin(sp?) and from the pixs this is the way i think it goes togather. And sorry for the long post just trying to be clearer than mud in explaining it.


-Charles

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#9
In reply to #8

Re: Husqvarna's built-in chain brake problem-repair how-to

02/23/2008 3:18 AM

Charles,

I've no problem with your using all the words you need, so I thank you for being thorough. I'm going to have to print out your post and check out the suggestions with my manual open (so I don't have to occupy my hands and eyes with mouse and keyboard). The problem right now is that a huge cyclonic weather event is coming on shore here on the USA west coast. So I'll be fully engaged battening tarps on my roof and bailing water and such. So it might be a little while before I can get back to let you know about your suggestions. Your patience is appreciated.

CA

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#10
In reply to #9

Re: Husqvarna's built-in chain brake problem-repair how-to

02/23/2008 5:34 AM

Good luck with the weather. Hope you don't have any problems there.
Just glad to try to help. Like you said someone with a mind to see how something works
is what's needed. Anyway take your time and I hope it's helps.

-Charles

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#47
In reply to #10

Re: Husqvarna's built-in chain brake problem-repair how-to

03/10/2008 8:34 PM

Charles,

Thanks again for the good wishes.

For response to your message (#8), please see posting #42, et seq.

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#13
In reply to #9

Re: Husqvarna's built-in chain brake problem-repair how-to

02/23/2008 10:15 AM

Why not go to your local Husq dealer and see if they will let you examine a working chain brake assy, i.e., lay yours and a working one side by side and see how they differ.

I have gotten to know my Husqvarna dealer very well over the years and their mechanics would bend over backward to help me resolve such a problem had I had one such as yours.

-John

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#16
In reply to #13

Re: Husqvarna's built-in chain brake problem-repair how-to

02/23/2008 12:04 PM

John...

Sure wish I could say the same...instead of A _ _ _ _ _ es. And, they were unable to convince me they knew anything about it; just tried to convince me that it was somehow my fault if a new saw fails totally after a short period of use, or a period of storage in its case. When I surprised them and asked if they knew "anything about the chain brake assembly" they were suddenly tongue-tied and stuttering... That's when they started getting uppity and began trying the old intimidation ploy. (Having had to teach two previous service shops here (both now out of business) how to diagnose and fix my riding mower, there's was no way I was going to let this one touch anything belonging to me.)

You are indeed fortunate to have a truly supportive dealer, with knowledgeable service personnel on your side; I'm finding such to be a dying breed; and, as the old-timers fade away, it's getting harder and harder to find people with good small engine and mechanical skills. Your location (somewhere in GA?) close to the east coast could also be a factor. Good mechanics (to me) have seemed harder to find the farther west you go. Out here it seems to be more about giving the good talk, but performance doesn't always back up the words when it comes to things mechanical.

Wouldn't it be nice if your mechanic could join in this conversation. He might even have actual drawings from the source, or shop manual/procedure that would accurately depict or describe the assembly procedure.

Thanks for the input and feel free to jump in whenever...

CA

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Anonymous Poster
#11

Re: Husqvarna's built-in chain brake problem-repair how-to

02/23/2008 9:17 AM

I've has exactly the same p roblem with my Huskgvarna saws

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#17
In reply to #11

Re: Husqvarna's built-in chain brake problem-repair how-to

02/23/2008 12:13 PM

#11, judging by our shared experience and the stories (links) I'm discovering on these threads, I beginning to become disheartened about buying the supposedly superior Husqvarna brand. Maybe ole Husqy needs to find themselves on the receiving end of a class action in court? Any ambitious lawyers reading this?

Anyway, hopefully both our problems might soon be over.

CA

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#20
In reply to #17

Re: Husqvarna's built-in chain brake problem-repair how-to

02/23/2008 2:25 PM

Likewise I have and old Husky and it worked very well. Then the case cracked and it being integral either its junk or I get coated with gas.

I've replaced with a Remington electric and wow! Light weight and the warranty says if it ever does not work return it!

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#48
In reply to #20

Re: Husqvarna's built-in chain brake problem-repair how-to

03/10/2008 8:52 PM

Thank you. See 20 ref 17 in posting #36.

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#21
In reply to #17

Re: Husqvarna's built-in chain brake problem-repair how-to

02/23/2008 5:00 PM

Just get a Stihl and be done with it.

Or better yet, get a predator like this one.

-John

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#49
In reply to #21

Re: Husqvarna's built-in chain brake problem-repair how-to

03/10/2008 8:55 PM

Thanks for the advise. Please see "20 ref 17" in post #36.

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#51
In reply to #11

Re: Husqvarna's built-in chain brake problem-repair how-to

03/11/2008 8:03 AM

Guest,

See also post 36 and "classification 5" titled thread for more info and answers.

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#12

Re: Husqvarna's built-in chain brake problem-repair how-to

02/23/2008 9:48 AM

(Third try: lost link TWICE last night, and finally gave up, after doing two writeups). I think metalSmiths has now covered most of the issues very well, but I think I may still have a little to add.

"Guest" (post 7) had a link that mentioned a small pin, which I've been unable to find in the photos. Could I ask you [after the battening down, and likely the hunkering, and the later uncovering functions have been completed] to "point" to it? Also, could you photograph the multi-directional spring in several positions? I think I'm understanding how it is shaped, but line drawing are a terrible way to describe wireforms. Scanning poor illustrations and displaying on a monitor does not magically improve them, oddly enough.

My "helpful information", if I'm right, is another clue: your second photograph, especially, shows the imprint of that very spring right on the flange of P/N 501 76 81-01, from about 6:30 to 3:00 o'clock [12-hour face]. I think it will be the end turn of the multi-turn torsion spring portion which rests there, concentric with the pivot axis formed around P/N 725 52 93-56 and the mating ones. The end turn on the coil will be faintly worn to match, and the orientation should be defined by the two surfaces. Following the same logic may locate the bearing surfaces of each lever section, or the cam-like function that metalSmiths (Charles) describes. Good luck with the weather!

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#14
In reply to #12

Re: Husqvarna's built-in chain brake problem-repair how-to

02/23/2008 11:07 AM

"...shows the imprint of that very spring right on the flange of P/N 501 76 81-01, from about 6:30 to 3:00 o'clock [12-hour face]. I think it will be the end turn of the multi-turn torsion spring portion which rests there, concentric with the pivot axis formed around P/N 725 52 93-56 and the mating ones. The end turn on the coil will be faintly worn to match, and the orientation should be defined by the two surfaces. Following..."

Ron

Ron, a quick reply to the above-quoted part of your message. If we are to believe that part of the drawing (which I don't really), then the multi-torsion spring will somehow be "affixed" outside the handle (hanging in mid-air, so to speak) after the brake/AKB unit assembly is assembled and installed on the saw. (The most glaring example of the ineptitude of Husqvarna's tech pubs department; and probably their design group as well.) Having worked on many publications myself, I am of the opinion that the writer didn't have a clue just how to interpret drawings and sketches provided by engineering, or how to instruct the artist/draftsperson; was too timid or intimidated to "challenge" engineering for clarification; the artist, too, didn't know or didn't bother; and the company itself didn't really care what kind of garbage went into its manuals. I doubt very much that the best drafts persons available to Husqvarna are ones who would merit no better than D+ in a basic, high school level drafting course.

Now that I've had a chance to vent...

I did check out the possibility of the spring's being placed where it "pivots" on the brake handle's pivot (inside the brake handle). Even if it could be so installed, and the handle re-mounted, the spring would not interface with else (could perform no function other than rattling about). So I think the springs placement in the drawing was simply the result of fudging by artist and writer to make an inconvenient problem go away. I do think Charles is on to something but need more time to prepare response....

I checked the link (guest #7) but have not as yet attempted to relate the part about the pin and the modifications to the drawings. Will advise when able...

Now it's time to batten down, and make a run for flashlight batteries, as we anticipate being in the dark tonight...possibly a few days judging by the last full storm that passed through. What a weird year for weather this has been!

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#24
In reply to #14

Re: Husqvarna's built-in chain brake problem-repair how-to

02/23/2008 9:16 PM

Keep in mind that I'm looking at your photographs, not the drawings, for the imprint. As it happens, that's exactly where it is shown on the drawing, with the extended centerline of the pivot passing through the coiled part of the spring. I would GUESS that it gets trapped between the case and cover, but that's only a guess with no hands-on. Unless you tried assembling it that way and left the mark later, that is where it used to be.

I've got a few chainsaws myself, though no Huskies. My largest is an 11-hp antique Mercury-Kiekhaefer two-man (unlike the video clip of Predator, the second man is at the business end of the bar!!!). It runs a conventional carb from before the diaphragm types came along, and the bar itself can be rotated into a horizontal position for felling, and back to vertical for bucking. The mechanism that clamps it is like a v-band clamp for a fiberboard drum. Like everything I've got, it is too old to have an anti-kickback or brake mechanism. I've got two bars for it, with the larger one a 54 incher, if I recall. Here's the military version: http://www.mil-veh.org/archives/05-01/0390.html. The rotating joint is roughly halfway between the starter rewind housing and the clutch (which aligns with the drive sprocket); you're looking at the rotation joint edge-on.

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#45
In reply to #12

Re: Husqvarna's built-in chain brake problem-repair how-to

03/10/2008 10:42 AM

This post has turned out to be the key to solving... Kudos for Ron's powers of observation. And a Good answer vote. The post deserves some more for sure.

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#15

Re: Husqvarna's built-in chain brake problem-repair how-to

02/23/2008 11:42 AM

Howdy,

I looked long and hard at the pic's and all looks okay. Have you lubricated the clutch drum bearing and the band itself? Check chain is fitted to proper tension and no burrs are on the bar. Check there is no obstruction to air flow into the filter or out of the exhaust. There is adequate properly mixed gas?

The kickback bar should not be under tension which the photo shows. Tension occurs when the kickback chain brake actuates.

If any binding occurs you should return it to the dealer or service agent and require them to fix it.

The problem may not be obvious...

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#22

Re: Husqvarna's built-in chain brake problem-repair how-to

02/23/2008 5:42 PM

interestingthe unit has 60 hours running time? how did you get the unit to operate that long with the band in what appears to be a reversed position? go back to the dealer raise hell if that doesn't help you have two options, send a letter of intent to the nearest consumer fraud investigator i8n your state relate what you are encountering then call a press conference with a local preferably cable t.v. company show them one running show them yours that scares the hell out of husky execs.

the will likely replace it n.c. to avoid litigation.

'da ber

p.s. it worked for us when the beetle trannies went boom 4 X

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#25

Re: Husqvarna's built-in chain brake problem-repair how-to

02/24/2008 12:05 AM

CowAnon,Whoa boy! don't take anything else apart, if you have, try to put it right back the way you found it and don't tell anyone you took the thing apart. There is nothing wrong with your saw. The clutch brake is in the applied position as evidenced in your first photo. The brake handle is in the most forward position, as it is against the stop just to the left of the pivot. See the little orange tab against the black handle? This is the brake applied position. Also look at the brake band itself. In the brake off position it will lay completely against the plastic rib surrounding it. To release the brake pull the handle in the direction of the rear of the saw and release. Its' easier with the cover on the saw but with some effort you can do it with it off. There will be a loud click or "pop" and the handle will return to an intermediate position. Refer to pages 9 and 10 of your instruction manual for a complete explanation of the operation of the chain brake. The Husky is a great saw capable of many hours of trouble free operation. I live in a house built in 1908 in eastern Colorado and heat exclusively with an Ashley wood stove so I am running the chain saw almost every day. I wouldn't waste my money on a Stihl or a Pouland as other posters have suggested. By the way you're not the first guy to be baffled by the Husky chain brake, I had a friend return a brand new saw to the retailer when the chain wouldn't move after he started it. The retailer didn't hesitate and gave him another saw. My friend finally read the instruction manual when the second saw wouldn't work either! Of course he hadn't released the brake!

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#26
In reply to #25

Re: Husqvarna's built-in chain brake problem-repair how-to

02/24/2008 7:16 AM

Its obvious the original poster has made a mistake in not pulling the release back far enough to disengage the brake .If it has been taken apart it would be easier to simply buy a new one .I have run Husky's for over 20 years the brake can easily be adjusted with spring tension or strap length .I would suggest chainsaws should be left to professionals and the fact the poster cannot figure out the basics reveals he should stay away from such a dangerous tool . In the same way a layman should stay away from electricity . Hire a pro and do what you do best , a quick look on line will demonstrate the devastating injuries that result from playing with chainsaws .Sell it!!!

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#29
In reply to #26

Re: Husqvarna's built-in chain brake problem-repair how-to

02/27/2008 4:47 PM

Its obvious the original poster has made a mistake in not pulling the release back far enough to disengage the brake .If it has been taken apart it would be easier to simply buy a new one .I have run Husky's for over 20 years the brake can easily be adjusted with spring tension or strap length .I would suggest chainsaws should be left to professionals and the fact the poster cannot figure out the basics reveals he should stay away from such a dangerous tool . In the same way a layman should stay away from electricity . Hire a pro and do what you do best , a quick look on line will demonstrate the devastating injuries that result from playing with chainsaws .Sell it!!!

That is what a more perceptive "helper" would more likely have done before posting such remarks. Indeed, if post-er of that comment was as smart and "professional" as s/he thinks, s/he might instead have:

  1. Hesitated to unwittingly implicitly or inferentially insult all other respondents, and all other members, who might wish to provide assistance with, or convey personal knowledge about, the question.
  2. Realized that what can't be tangibly seen and fully known cannot be quite so utterly "obvious."
  3. Realized that boasting about 20 year's experience, as if to claim superior expertise, and yet not being able to offer one scintilla of verifiable information about the assembly is tantamount to confessing...a kind of stupidity.
  4. Understood that neither operating nor repairing chainsaws is a "profession."
  5. Have gained sufficient education to understand that most electricians, and probably most chain saw repairmen as well, are, in fact, laymen (i.e., not of the clergy).
  6. Have fathomed (being a person with total technical familiarity...) that talk of danger and injuries from "playing" with (in this case) an unstartable saw is both immaterial and irrelevant.
  7. Have perceived the inconsistencies and ambiguities when attempting to "sell" a saw in need of reassembly in order to be started, or...
  8. The rationalities of purchasing, at retail, a new saw subassembly to replace a scarcely used, and evidently non-defective, saw subassembly...only for the purpose of selling both the barely used saw and the brand-new subassembly, and furthermore...
  9. As an aficionado of saws Husky, might have perceived the opportunity (to have a near-new saw to replace or supplement that 20-year-old saw) and offered to buy the saw as is, less repair cost, in the self-assured knowledge that s/he would immediately and easily (and cheaply) be able to correct the saw's problem.
  10. Have gotten more information about how the saw was operated before presuming, based on no tangible evidence (and even evidence to the contrary), the capabilities of the saw owner.
  11. Have been able to distinguish between "the basics" and the "advanced" when it comes to saw design and repairs.
  12. Have known that to say or imply that the brakes of all "Husky" saws—including those under 20 years of age—can be "easily" adjusted "with(?) spring tension" or "with strap length" reveals a basic misunderstanding of the subject; and of the design criteria of modern saws.
  13. Would have understood...when s/he read (if s/he read before spouting) about the unsuccessful attempt to engage so-called "pros," to fix the flaw in the almost new saw.
  14. Might have been aware, based on 20 years of (genuine) Husqvarna chain saw experience (or any small-engine product experience for that matter), that new-product flaws after purchase can, and do (more frequently that people would prefer to believe), arise as a result of such things as factory assembly workmanship defects, original design or pre-/post-production testing oversights, inadequate field failure tracking, incorrect or deficient owner manual maintenance procedures...and the like.
  15. Would have comprehended that such "answers" as s/he was able to offer could be seen by many "professionals" (members and non-members alike; and including perhaps those who demonstrated both grace and tact by offering encouragement while admitting unfamiliarity...) as a not-so-transparent attempt to cover up one's own (privately-admitted) paucity of either, knowledge about the specific problem, or mechanical problem solving skills in general.

Or might have simply recognized a need for self-restraint, and simply have been content to observe but not speak...there being (obviously) no immediate necessity to speak.

CAPO

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#32
In reply to #29

Re: Husqvarna's built-in chain brake problem-repair how-to

02/28/2008 7:14 AM

ok blow hard

The fact is the entire assembly cost only $30 so why make such a big deal out of it.

If it is a new saw the dealer should offer a free replacement if it is in fact defective and the fact it was disassembled would probably void that warranty .

Which brings me to the conclusion that this whole issue is a waste of time and I will restate the fact that chainsaws are very dangerous and should only be used by professionals.

I guess every wiener needs to prove his manhood so go ahead have fun .

And when your in the ER remember I told you so.

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#33
In reply to #29

Re: Husqvarna's built-in chain brake problem-repair how-to

02/29/2008 12:03 AM

Well said.

Tact along with wisdom doesn't come in a box it has to be sought...

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#78
In reply to #29

Re: Husqvarna's built-in chain brake problem-repair how-to

05/25/2010 3:41 PM

shut up, bleeding heart. grow a pair.

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#79
In reply to #78

Re: Husqvarna's built-in chain brake problem-repair how-to

05/25/2010 5:07 PM

"shut up, bleeding heart. grow a pair."

Brave words, coming from someone unwilling to disclose even a username! I'm quite impressed [but I did not say "favorably impressed". Do you know why, Guest #78?].

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#96
In reply to #25

Re: Husqvarna's built-in chain brake problem-repair how-to

11/05/2011 6:00 PM

I had two problems with this brake. After it jammed the first time I couldn't get the cover off since the band is tight around the drum. I purchased a new brake assembly since I broke the first one trying to get it off and had the exact same problem after using the saw a short while. This should not happen.

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#27

Re: Husqvarna's built-in chain brake problem-repair how-to

02/24/2008 6:06 PM

Doese the motor run and the brake work without the bar installed? Perhaps the chain is short and the bar is being retracted to a position where the end of the bar is rubbing on the clutch?

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#28

Re: Husqvarna's built-in chain brake problem-repair how-to

02/24/2008 6:45 PM

before you put back cover with brake pull back brake handle push forward to reset brake should have hear click. put back cover on saw should fit if blade in right place install bolt nuts ajust chain not to tight tightin nuts try saw should work may have to reset brake if chain then go out and saw a cord of wood do not forget to put some bar oil in the saw

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#30

Re: Husqvarna's built-in chain brake problem-repair how-to

02/27/2008 7:29 PM

Didn't read the whole item, but "Yep, been there done that." The answer was simple (after about five cups of coffee and a "stop and think" moment.) (HUSKVARNA 350)

What had happened in my case was that after removing the cover to fit a new chain, in my zeal to clean away all the muck, I had inadvertently activated the "anti kickback" lock and as in your pictures, the "band" was then clamped down.

If you look where the handle fits into the cover, there is (in my case) a three toothed "gear" that allowed the handle to activate the band. Refer to your three "real life" images. What has happened is the chain brake has been activated. You need to de-activate this. (You will know when this has been achieved as the band will be back snug against the outside surface of the plastic recess.

This is NOT an easy task with the unit dismantled, but can be done. You need to

1) Find in the mechanism where the handle would normally be positioned.

2) Determine which direction it needs to go to "release" the brake

3) develop a "tool" to do this.

3A) BE VERY CAREFUL from here on. The device has a cam and VERY strong springs and can jam fingers or send a tool across the room.

4) cause the device to rotate and release the brake. (You will see the "long spring" relax to a closer coil spacing.)

The difficulty comes from the lack of leverage available when compared to using the forearm guard with the saw fully assembled.

My HUSKY has had a few minor issues, but is now around 400 hours use making fence posts, firewood, sheds (from timber cut on the property) heavy duty furniture, clearing storm debris and other general farm use.

Hope this has helped.

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#69
In reply to #30

Re: Husqvarna's built-in chain brake problem-repair how-to

10/18/2009 4:26 PM

Hey "Traditional". I am having the EXACT same problem as the other man. I wish I had the same superior genes that you apparently possess so I could talk down to the rest of the human race. I have only been "playing" with chain saws for 26 years now and have not made even a trip to the store for bandages. Since you are so smart, what day are me and the other guy going to the emergency room? Mark von Kutzleben

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#70
In reply to #30

Re: Husqvarna's built-in chain brake problem-repair how-to

11/05/2009 12:31 AM

This is a follow-on to Just an Engineer's answer (#30), with a suggestion for the appropriate tool.
It just happened to me, with a borrowed Husqvarna 455. This was my first experience with a chainsaw having a brake; must have had a kickback that triggered the brake, or just accidentally hit the trigger handle the wrong way, and didn't know about disengaging or resetting the brake before removing the cover. Naturally the engine couldn't run the chain.
So stupidly, and with some difficulty, I removed the cover with the contracted brake-spring band. Then removed the linkage/coil spring cover and was whelmed by dismay! The coil spring in the 455 is very stiff and heavily preloaded. No way I'm going to fool with that. Tried unsuccessfully to turn the lobed wheel that engages with the handle and drives the linkage to the coil spring, using plain water pump pliers, but they kept slipping off without moving it a bit. I'd call the linkage a bistable overcenter type, the same principle found in wall switches, but with the cocked position being only slightly overcenter and the triggered position way overcenter, providing a staggering mechanical disadvantage to resetting. Didn't like the idea of using the brake handle to do this as several answers suggest, because I didn't want to reattach the cover and have to force that contracted brake band back over the flywheel, and if I didn't reattach the cover, the slightly chewed looking engagement lugs on the handle would not fully engage and might slip off causing more chewing.
Finally, while I was resignedly contemplating making a special tool from pipe (following #30's advice), my daughter suggested I try my narrow-nose visegrips. Well, why not, nothing better suggested itself. So I reattached the trigger/coil spring cover, clamped visegrips on the narrowest part of the long wheel lobe that actually engages with the linkage, oriented with the visegrips' long axis perpendicular to the plane of the wheel. Then used plain pliers to turn the visegrips, attached down near the ends of their jaws, with two people holding down the cover. Too easy! It snapped right into the cocked position. Luckily the handle is still good to trigger and reset the brake so I'm back in business. Visegrips rule!
Thanks to many contributors who made the layout and function of the mechanism understandable.

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#104
In reply to #70

Re: Husqvarna's built-in chain brake problem-repair how-to

12/08/2012 10:20 PM

Thanks Kirchwey. Your daughter's very smart. The vise grip and pliers worked great. That was a frustrating problem to have with a new chainsaw. I made the mistake of taking the clutch cover off with the front hand guard in the forward position/locked. Husqvarna should include more information in their manual on troubleshooting. With your tip I was able to get part of my storm clean-up done before the sun went down. Thanks again.

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#31

Re: Husqvarna's built-in chain brake problem-repair how-to

02/28/2008 4:54 AM

Just an, Gentlemen,

Like some prior posts, I find post #30 to be uncanny (that is to say...on the mark based on my own experiences attempting repairs) in many ways...and I think (with all the help from everyone) we are getting closer even if not quite there.

In the morning I will resume, working offline, to respond to everyone; I also hope, with your presumed agreement, to attempt to answer similar suggestions jointly so as to consolidate threads in order to keep the discussion from becoming too unwieldy for me. This will take some doing and a bit of time...and I'm also pondering whether to post pics, the ones above and perhaps others, to a web site so that viewing the pics (accessed from any any post by me) in a separate window might make it easier to discuss the matter without the need for scrolling as the discussion grows longer. I ask your patience while I work on this, and Will be back with detailed responses (and pertinent anecdotes) ASAP. Again, thanks and please stand by. (and no need to reply to this, please)

CA

BTW, I want to thank the earlier post-ers for waiting while I dealt with the recent storm events. As it turned out the weather forecasters were substantially off the mark in terms of severity...I think the worst part veered off on another track. Unfortunately, the forecast was the only thing I had to go by—the forecast revision didn't come until after the worst didn't come!—so I wasn't spared from spending just as much time, preparing/waiting/hunkering down, as if the storm had been as monstrous in my area as promised.

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#34
In reply to #31

Re: Husqvarna's built-in chain brake problem-repair how-to

02/29/2008 4:58 AM

Classified (See legend at bottom)

Post indentures

Commentary by

Comment/Reply

status

0

11 rf O

-Guest #11—

commiserates about same problem w/ husky

answered

0

17 rf 1l

-CowAnon—

acknowledge, return though, mention class action

NA

0

19 ref 18

-bwire—

reiterated 16 off track discussion

Ackn pending

0

20 rf 17

-bwire—

General about Husky experience, commiserating

Ackn pending

0

24 rf 14

-Ron—

explaining how got impression—suggest how user might have moved? REPLY

NA

14/5 ref O-Fierce Allegiance-about brake engage & how to unengageanswered

1

6 ref 4,5

-CowAnon—

Try explain brake not miss-set not grasped by all

NA

1,

4

15 ref O-bwire—general preventive maintenance advise; guesses about fotos, suggests coerce dealer. Unclear if fotos/OPquestion not misinterpretedReply pending
1,

4

22 rf O-Guest #22—Misread? Seems confused 60 min. for 60hours; possible dwg misread, suggests

suggests action to coerce seller.

Pending reply. about hours used
125 rf O-shart4legged—instruct how use brake (possibly not read/comprehend OP, et seq fully)Pending Reply
126 rf 25traditional26 rf 25-traditional—about qualififications and dangers; Seems not read/understand question. Comment bit overwrought, nonapropos.Possible reply pending... to try clarify situation
2, 37 rf 6-Guest #7—About cocking mechanism, checking inside handle, link to forum. .Possible misunderstood Q.Answered...about linked forum posts only

2,3

18 rf 7

-CowAnon—

discuss link/chain reworking—dismissed handle.part..

NA

323 rf 6-garth—more about brake engage, recommend improvise by modifyingReply pending
413 rf 9-Johnjohn—Dealer anecdote and recommend ask dealer helpAnswered

4

16 rf 13

-CowAnon—

explain and give anecdote why won't work here, tried already

NA

1, 4

15 ref O-bwire—

general preventive maintenance advise & guesses about causees; possible misinterpreted foto; suggest coerce dealer/agent

Reply pending about action against seller

1, 4

22 rf O-Guest #22—

Seems confused 60 min. for 60hours; possible dwg misread, Suggests confront/threat action against seller

Reply pending about actionability
58 rf O (&10 rf 9)-MetalSmiths—Good discuss about the braking part interfaces, suggests plausible proper fit. Ideas consistent w/ repair observations...

(& acknowledged standby request)

Reply pending about post correspondence to repair attempt observations

0

9 ref 8

-CowAnon—

ask time to review, PENDING REPLY

NA

512 ref O (actually 6)-Ron—Agrees w/ Metal smith, asks for pic marking improvised pin mentioned in linked forum. And views of multi-helix spring

thinks spring concentric w/pivot

Reply pending about foto of pin and spring
514 rf 12-CowAnon—Checking link and pin...

checked out idea of spring pivot on handle pivot more

See previous
512 ref O (actually 6)-Ron—

Agrees w/ Metal smith, asks pix of links, thinks spring concentric w/pivot ...more

Answered & rebutted idea about spring pivot on handle pivot.

5

14 rf 12

-CowAnon—

Checking link and pin... rechecked idea of spring pivot on handle pivot Idea& dwg rebutted. Added commentary about Husq tech pubs

NA

530 rf O (and 6 metal...)-Just an Engineer)-Plausible ideas about actual assembly... consistent w/repair CA's repair attempt observations!!reply about related saws and similar observations pending

Consolidated replies pending

31 rf O/5/all

-CowAnon—

thanks all and request standby for consolidated replies

NA

Legend: Response/recommendation classification code::

0. Class not applicable (na) or OT (tangential or off topic)

  1. Operator/maintainer error needs correction
  2. Flaw due to failure mode
  3. Failure mode due to Mfg/Setup Defect resolvable by modification
  4. Failure mode due to Mfg/Setup Defect resolvable by action by/against mfr, dealer
  5. Hardware interface/reassembly & setup problem
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#35

Re: Husqvarna's...chain brake...repair how-to...Discuss by Class.- Introduction

03/04/2008 1:56 AM

So what was the meaning of the hidden summary outline just above? Besides the obvious (an encapsulation under categories, and status, of the discussion up to now). Based on that, I will post new thread starters, one for each Classification in the summary legend, in each of which discussion participants will be able, using the underlined captions, to locate their own inputs, and review status and/or current responses.

By this approach I am anticipating that all except the last Classification (Thread class 5) of responses will have been comprehensively answered...and laid to rest for further technical answers to the forum question. (although...not meant to discourage anecdotes and OT posts of interest posted in zero or other appropriate thread category).

By this means of moderation, ongoing discussion about the central topic will then, it is hoped, be restricted to messages related to (and posted under) the bottommost "Classification" thread...posts related to: Hardware interface/reassembly & setup problems (This will also make it easier for all to stay on the same page with minimum scrolling and re-reading.)

(Please note: A bit more work is needed before the last, category 5 thread is ready...so it might not appear as quickly after your read this. Your patience is appreciated.)

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#36

Husqv.chainbrake repair how-to...Classif'n 0 - Class not applicable

03/04/2008 2:06 AM
  • 1) Classification 0 - Class not applicable or OT (tangential or off topic)
    • a) 11 rf O-Guest #11—commiserates about same problem w/ husky
    • b) 17 rf 11-CowAnon—acknowledge, return though, mention class action
      • (1) But also see Classif'n 4 about problems w/ legal/administrative action.
    • c) 20 rf 17-bwire—General about Husky experience, commiserating
      • (1) Although mine is not "old," your post, bwire, raises a question: Did your saw frame (I assume the tank was integral w/ handle, like mine) break because of age/wear-and-tear, or because of impact, or both?
    • d) 21 ref 17-Johnjohn—suggest forfeit, stihl, link to predator pics
      • (1) No doubt, Johnjohn jests...and has good reason for pride in his Stihl. I only wish I had the $means, or chainsaw-produced $income, (and/or common stock holdings) to be able to donate the price of a new saw to a large manufacturing company like Husqvarna.
    • e) 19 ref 18-bwire—reiterated 18 off track discussion about saw chains
      • (1) Agreed, and I'm pleased that fellow showed me the light...before I forfeited the "stock" chain and purchased the real thing. My take is, that Husqvarna's was faced with a problem of how to adapt a powerful saw, originally intended for "logger use," to the consumer market—and how to stay clear of injury claims and government (consumer safety) agency interference. One way of "safety handicapping" the saw—this appears to be the most common for mass-marketed saws—would have been to fit a tip guard. Problem with that is that the saw becomes worthless for plunge cutting; where I can fell a tree up to 82-cm trunk size, a tip guard would have limited my saw to less that its nominal 41-cm bar length. Provisioning a less aggressive, "chipper" chain seems intended (apart from selling optional replacement chains) not only to render the saw less potentially hazardous (because the cutters don't "bite wood" as aggressively), it also eliminates a different, perhaps more likely, downside (hazard) of aggressive (standard) felling chains: compared to a "tamed" chain, standard chains cannot be used, either as safely or as effectively, for smaller jobs such as sapling/sucker/small branch removal and brush clearing (because smaller, flexible "branches" cannot resist the biting & pulling of the chain, and tend to be grabbed rather than cut clean...)—the kinds of work which Husqvarna probably figures many householders, farmers, and such will want a new saw to do. So my guess is, Husqvarna (which did not market through mass retailers at the time) figures: "Give them a tame saw to practice on; if they complain about wanting to cut logs (or about wearing out or burning chains), then (and only then) sell them the real-deal chain. The lesson here, seems to me, is: If you want to do multiple cutting tasks, either keep multiple, task-specific chains, or multiple, task-specific saws, on hand.
    • f) 24 rf 14-Ron—explaining how got impression about user's mislocating a part? Link to monster saw pic.
      • (1) Understood and answered. More: The M-K (link) was fascinating. That being a "military" saw, I tried to imagine its use for "blazing" trails, in one fell swoop, in a forested battle theatre; and how efficiently such a "super powered" (what is essentially a) two-man whip saw could clear cut an old-growth stand. On the other hand, the saw seems to have one drawback unique to itself: just getting it through the woods to where a tree needs felling! Also, it looks to have the distinction among chain saws of being harder to carry than to use. J (More about saw assembly error under class 1.)
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#37

Husqv.chainbrake repair...Classif'n 1: Operator...error needs correction

03/04/2008 4:03 AM

Classification 1 - Operator/maintainer error needs correction

  • a) 4 & 5 ref O-Fierce Allegiance-about brake engage and how to disengage...
    • i) Previously answered: 6 ref 4,5- CowAnon--try explain brake not miss-set (possibly not read/grasped by all)
  • b) 15 ref O-bwire—general maintenance advise and guesses about misinterpreted foto, coerce dealer,
    • i) As photos show, clutch, etc, parts are in near pristine condition and well maintained along with rest of saw. The "kickback bar under tension" comment simply restates the originally stated problem. OP asserts that all probable "component faults" outside the brake handle assy have been eliminated. Please see "class 1 general response," below. For answer to dealer actions, please see "Classification 4" thread, below.
  • c) 22 rf O-Guest #22—misread about hours used, suggests confront/threat action against dealer/mfr
    • i) The (idling and cutting) time-of-use originally stated was 60 minutes (more or less), not 60 hours. Please see Class-4 thread, below, for response to dealer-related suggestion.
  • d) 25 rf O-shart4legged—didn't comprehend, instructs how use brake
    • i) Reply: No, not baffled, or predisposed to be baffled, by chain brake operation; only by what seemed to have been an anomalous failure...and how to identify it by opening (and having already opened) the handle assembly where the failure has been reasonably isolated. Please see "class-1 general response, below, for more detail about owner actions...and why these have no bearing.... Also, note about owner manual: For anyone who wondered about my ascribing this problem as a seeming, manufacturing (i.e., built-in) defect, I also feel the manual itself could be a significant part of the problem. I have suggested previously how a correctly drawn, and accurate, exploded-view drawing should have made it possible to assemble the brake actuation components correctly. Aside from that, the owner manual maintenance instructions are both poorly written and inadequate...in places even flat-out wrong (both text and illustrations). So, as is too often the case, if routine maintenance instructions are not accurate, it will be difficult to know whether or not a failure was actually caused by the manual! (Naturally, the mfr's customer service and authorized repairers seldom if ever read their own manuals—and will refuse to read them if told the manuals contain blatant errors. Their attitude is both: "Who reads manuals? And "See no evil; blame the customer."
  • e) 26 rf 25-traditional—about qualifications and dangers;
    • i) Guest CAPA appears to have pretty much covered it. Seems that "evidence of things not seen" was the guiding principle for the devoutly offered corrective actions.
  • f) 27 ref O-Guest #27—didn't read/comprehend—errant suggestions.
    • i) See next.
  • g) 28=27 ref O-Guest #27/28—more advise on saw setup—consolidated w/27-rf-O
    • i) Just in case...it's a gasoline-powered, 2-stroke, reciprocating engine. Please study the saw photo's (above), and see Class-2, -3, and -5 threads (below) to convince yourself that the answers to you questions are immaterial to the problem. I will be glad to further explain and illustrate clutch and brake subsystems function and interoperability if you wish to request...in private message.
  • h) General response to suggestions involving operation and maintenance error on the part of saw owner:
    • i) It has been stated or implied, both, that manual engagement (by pushing handle) of the clutch binder (component of chain brake) and (conversely: by pulling handle) manual "arming" (setting, cocking...) of the chain brake mechanism to its kickback-safe/clutch-binder-released/chain-un-braked/engine-full-rev-capable/engine-off-maintenance settings were somehow misunderstood—even that: but for absence of such knowledge (or of owner aptitude or "professional" standing), the saw will be found, or would have been found, to be free of flaw and functioning optimally. The following history (and clarification) is offered in hopes of allaying and putting to rest all such concerns about owner's general saw function understanding:
      • (1) Prior to first start of the new saw engine, and prior to powered use for cutting, all operation and maintenance procedures were carefully reviewed and "dry run" to ensure complete facility with using and maintaining the saw.
      • (2) After that, and before the apparent failure occurred (and apart from instances of preventive inertial testing of anti-kickback), the chain-brake/kick-back-safe mechanism had been successfully manually operated (with hearing of so-called "pops") numerous times in order to:
        • (a) Enable the saw for full rev cutting;
        • (b) Idle the chain (for safety's sake and to alleviate re-cranks/restarts) while resting the (running-at-idle) saw on the ground between cuts (while moving logs, clearing obstructions, gaining footing, reconfirming fall paths, etc.)
      • (3) It only after (2), near the end of only the most recent cutting job session that a problem first arose:
        • (a) Having killed the engine in "chain-idle" mode, the saw was restarted and attempted to be revved'ed to perform a cut, but would not accelerate normally...
          • (i) Realizing (or not) that the saw was in "safe idle," the brake handle was pushed (or was it, pulled and pushed?)...still, nothing.
          • (ii) The engine was killed and a superficial check of possible "points of resistance was checked:
            • 1. Chain tension/heat/lube reserve tank
            • 2. Bar sprocket lube
            • 3. Fuel level
            • 4. Plug cable
            • 5. Chain mobility being the only thing found amiss, pushing (but not forcing) the brake (release) handle, and then restarting & and revving'ing did not clear, or reveal, the problem.
            • 6. Time (for cool-down & teardown diagnostics) being then presently unavailable, election was made to shutdown, blow clean, drain fuel and lube, and stow the saw in its case, with intention of revisiting diagnostics later on...preliminary hypotheses being:
              • a. That since engine start/idle and throttle control were functioning normally, there should be little difficulty pinpointing the flaw
              • b. That, having unseated considerable "blow back" debris during compressed air saw cleaning, the problem might be as simple as an obstructing particle(s) (in the chain drive sprocket area) needing removal—or perhaps the compressed air cleaning might prove to have cleared the problem at next saw use.
            • 7. Although "later on" proved later than anticipated, next attempted "use" of the saw immediately revealed a need for to teardown to check for chain-drive torque output obstructions, starting in the sprocket area. It was then, when removing brake assembly and sprocket cover, that...
              • a. ...sprocket-drive drum was found to be seized by the brake binder—and no sensible amount of brake handle manipulation would open the binder to permit easy brake assembly removal for "getting at" the sprocket.
              • b. ...that preliminary failure hypothesis was expanded to include anomalous (i.e., not "wear & tear" or "use-induced") defect inside the chain brake assembly.
              • c. ...it became necessary to add some 3-In-OneTM (between binder and drum) to aid in prying brake assy and binder strap free from drum and off of the saw.

                • i. Sprocket clutch was found to be as shown at left (& in "0" post), and free of defect except for a slightly misplaced retractor spring ...possibly displaced during brake assy removal; possibly displaced during prior use; possible installed wrong at factory or by seller during delivery set-up/prep; but, in any event, not capable of preventing saw operation, or causing the observed failure symptoms.
            • 8. Subsequent, painstakingly difficult assembly (and attempted reassembly) of the brake assembly, followed by fruitless interactions with Husqv's US corporate and with local authorized service has finally led to this online discussion...and (now, and having eliminated all other failure mechanisms) to the (remaining-to-be-culminated) specific discussion of brake-assembly mechanical details, below, in the "Classification 5" discussion thread. Please continue reading/responding there.
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#38

Husqv...repair...Classif'n 2/3: Flaw due to failure...resolvable by modification

03/04/2008 4:12 AM

Classification 2/3 - Flaw due to failure mode/Failure mode due to Mfg/Setup Defect resolvable by modification

  • a) 7 rf 6-Guest #7—cocking mechanism, check inside handle, link to forum
    • i) Comment essentially restates the original question.
    • ii) Previously answered: 18-rf-7-CowAnon—discuss link/chain reworking—ignored handle part.
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#39

Husqv...repair...Classif'n 3: Failure...Mfg...Defect resolvable by modification

03/04/2008 5:33 AM

Classification 3 - Failure mode due to Mfg/Setup Defect resolvable by modification

  • a) 23 rf 6-garth—more about brake engage, recommend improvise by modifying brake actuation spring
    • i) It is premature to say if that (changing the helical spring) might work. If problem persists after brake handle assembly is reassembled and serviced (helix spring lubed? Manual ignores this maintenance) then this could be a solution(?)...this would also imply a design flaw. One problem, however, might be the degree to which the helix spring is spec'd in relation to the multi-action "trigger" spring, and the possibility that both would need to be changed (a very dubious if not impossible undertaking) in order for the kickback function to trigger, either inertially or by deflection of hand from saw handle. (Please see more about this aspect in Class-5 thread.)
    • (Note: by design flaw is also included flaw in maintenance documentation (one of others but not so glaring...because it's not there) in owner's manual. There was no instruction for periodic lubing of the helical spring or spring containment channel...to prevent its binding against walls of compliant, plastic channel in which it rests...under high compression during saw use--and saw use vibration! If this (lack of lube instruction) was an "informed omission" (which I doubt) the the inference is...a material selection (or testing omission) design flaw: where it was "decided" that the material surface property [and resilience] of plastic would provide sufficient lubricity for a powerful compression spring bearing against the plastic. When I checked this aspect by adding some lube, the spring did become more mobile when compressed/extended. When I attempted to discuss this and other design flaws...Husqvarna was (or feigned) incredulity ["We (our engineers) are the experts..." and all that...] I then expressed (my own) incredulity...stating that although it is not uncommon to bring products (designs) hastily to market expecting to resolve flaws after initial distribution...how could they know of flaws in the absence of an effective field failure tracking system. When Husqvarna replied that they do have such a system...it was then that the flaw with their failure tracking system (and, likely, of many other commercial-grade mfrs as well) became evident. Upon closer examination, Husqvarna revealed that the only flaws reported to their tracking system were flaws corrected by "authorized service" under warranty. No amount of persuasion could convince the Husq. customer rep that such an approach (such a restriction) essentially blinds the tracking system ever seeing the greater majority of flaws...such as the chain brake flaw (and the manual flaws). The "other side of the coin," though, is that skilled warranty service techs are in increasingly short supply for mfrs. A mfr's mass marketing of products with flaws, and blinding itself to the existence of design oversights...probably goes a long way [creates enough make work] towards keeping (at least a) sufficient number of service agencies both occupied (doing warranty and non-warranty defect work) and solvent.)
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#40

Husqv...repair...Classif'n 4: ...due to...Defect...action against mfr, dealer

03/04/2008 6:04 AM

Classification 4 - Failure mode due to Mfg/Setup Defect resolvable by action by/against mfr, dealer

  • a) 13 rf 9-Johnjohn—Dealer anecdote and recommend as dealer help
    • i) 16 rf 13-CowAnon—explain and gave anecdote why won't work in this case...tried already
  • b) 15 ref O-bwire—general maintenance advise and guesses about misinterpreted foto, coerce involving dealer,......ALSO CLASS 1
    • i) See next.
  • c) 22 rf O-Guest #22—misread about hours used, suggests confront/threat action against dealer/mfr ....also class 1
    • i) See general reply regarding actions against seller, next:
  • d) In addition to the leverage rationales, #22 Guest's [VW] "beetle trannies" experience offers a seemingly surefire, as well as "low-risk," approach to obtaining remedy; but, looking at a bigger picture, it also reveals why Husqvarna and its distributors (or any similar potential "defendants" (even those few which have not as yet sought "mfr's risk concealment" within large, corporate, retail box stores) are highly unlikely to be persuaded by leverage or legal tactics, whether threatened or actually initiated:
    • i) Saw mfrs & sellers would be mindful that whereas automobiles cost $thousands and more, most chain saws (and portable implements in general) sell for $hundreds or less; and therefore:
      • (1) ...that small-claims venues will deprive petitioner of any benefit of attorney representation.
      • (2) ...that the lesser skills of small claims arbiters are more likely to be exploitable by "corporate expertise."
      • (3) ...that small-claim petitioners are less likely, if at all, to be afforded the "normal" presumptions respecting litigant credibility; or full benefit of evidence presentation, subpoena or challenge; or even the full protection of procedural law.
      • (4) ...that—and possibly the most importantly—that only small claims defendants, but never plaintiffs, have the right to appeal "judgment" error...or simply judgments (right or wrong) they simply do not like.
      • (5) ...that even a buyer willing to spend disproportionately (both money and time) to be heard (where allowed) in "full" court is scarcely likely to find any lawyer willing to go to trial, or to press for "full" settlement including attorney fee.
      • (6) ....that, in general (this based on successful legal actions against GMC and Nissan MC), reasonable people will not be willing to invest the required, extraordinary time and lost opportunity (and aggravation) needed to prevail in a cause where only $hundreds is at stake; and where (even) "winning" is ultimately most likely to prove practically indistinguishable from losing.
    • ii) Whereas annual new & used vehicle purchases amount to millions (in buyer qty and $$ spent), chainsaw sales in any state jurisdiction are miniscule in comparison...for which reason—and because chainsaw sales constitute a virtually invisible portion of any state's economy—and because chainsaw owners have no "special interest" standing:
      • (1) Legislatures have no inducements to enact "car like" protections for chainsaw (and power tool) buyers.
      • (2) Consumer protection agencies (and such consumer-protective regulations as might be deemed to be applicable) are almost certain to ascribe lowest priority, if any, to inherent or anomalous flaws appearing occasionally in some (more or less) new chainsaws.
    • iii) Although consumers might be unaware, manufacturers are fully aware of the primary purpose of expressed warranties—to protect sellers—and they write them accordingly, for maximum seller (not buyer) value (both value of evaded liability, and value for promoting an image of perceived product/brand superiority).
      • (1) It is then (in the case at hand) no surprise (i.e., the manufacturer surely studied and took householder seasonal use/storage patterns into consideration...) that the my (the questioner's) chain brake anomaly occurred after the warranty period, not of reasonably expected saw use but, of ownership since purchase.
      • (2) Practically the only, and by far the best, chance of obtaining "legal" remedy...would entail an implicit warranty action based on "merchantability and fitness for purpose"—$300+ is scarcely a fair price for a power saw that saws only for an hour or so. But, even that approach, including the threat of such an action, is not without substantial difficulty of its own:
        • (a) Proving that a mfg defect created the "unfitness" could be an exceedingly expensive, possibly insurmountable, hurdle.
        • (b) Proving the negative—that purchaser did not cause the unfitness—could be equally problematic.
        • (c) Even the most cogent of arguments (esp. from other than Mfr's expert) is apt to "fly over" the heads of many judges.
        • (d) Use of "implicit warranty" (statutory or common law) as leverage or threat will be of no value, or doubtful value at best:
          • (i) Other than Mfr's or seller's lawyers (who will never be available), there will be scant chance of an employee having any clue about implicit warranties; or why he/she should feel threatened at the mention....
          • (ii) If such a person as does understand is approached, she/he is also likely to realize the emptiness of the threat—that it is unlikely to be carried out. "So, sue us"...is apt to be the end of the matter.
    • iv) Finally, in some regions (e.g., where small engine product markets are protectively (anti-competitively) carved up, legal threats and actions can ultimately prove more costly to "winning" customer than to "losing" merchant.
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#41

Husqv...repair...Classif'n 5: Hardware interface/reassembly & setup problem

03/04/2008 6:10 AM

Hardware interface/reassembly & setup problem

Coming soon

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#42

Husqv repair-Classif'n 5: Hardware...8 ref O-(&10 rf 9)-metalSmith

03/10/2008 6:18 AM

Classification 5 - Hardware interface/reassembly & setup problem

a) 8 ref O-(&10 rf 9)-metalSmiths—good, talking about the brake interfaces, suggests proper fit:

b) 9 ref 8-CowAnon—ask time to review, PENDING REPLY Updated reply continues next:

  • i) Charles, I have rephrased your MetalSmith comments in order to express what I interpreted you to be saying in your post (as captioned in a) above (please, let me know if, and where, my interpretation below is not what you meant). Following each rephrasing of each paragraph of your original comment, I inserted a response (it will appear in Italic type) to the foregoing material...presumably those "CA Response" comments will be the basic for continuing discussion.... So here goes with the first rephrased paragraph of your recommendations.
    • (1) "...the way I think the trigger spring (530 01 59-10) and the linkage (501 87 53-01) work together is: When the brake handle hand grip is in the rearward, pulled-back (towards saw operator) position, the linkage (ref 501 87 5453-01) must be straight, and not deflected, in order for it to compress the brake (actuation) spring (501 87 54-01). (If the linkage is not forcibly held in straight alignment (&or pushed into straight alignment as brake handle is pulled), then the great force capacity of the brake (helical) spring will cause the linkage to deflect, to collapse or remain collapsed)—to a "bent" configuration where it remains too short to compress the brake spring.)
    • (2) "Conversely, when the brake handle is pushed (or kickback "sprung") forward, the linkage (...53-01) must deflect (upward)—like a (beckoning) finger bending—to permit the (rearward) spring-guide plunger component of linkage assembly 501 87 53-01 to move forward under expanding 501 87 54-01 spring pressure, while simultaneously pulling on and closing (binding) the brake band around the clutch/brake drum; thus seizing and stopping the chain-drive sprocket and, with it, the saw chain.
    • (3) "Accordingly, whenever the brake handle is pulled rearward to release the brake (and/or to arm "kickback-safe" mode), the "trigger" spring (530 02 59-10) needs to somehow apply pressure to—to somehow restrict motion of—the linkage parts of 501 87 54-01 to keep them from deflecting—to keep the (brake-band-plunger-to-brake-handle) linkage straight (i.e., long enough) so that pulling the handle will, both, compress the 501 87 .54-01 spring and push against the brake band, forcing it to open wider and release the drum."
    • (4) CA response comment: Yes, it appears to me your description aptly describes the basic (manual) brake release and brake application functioning, at least insofar as all except how the kickback-safe- triggering mechanism works (but we can come to that later...).
  • ii) Now let us continue...with my interpretation of the second paragraph ofMetalSmith's message....below the illustration).
    • (1) MetalSmith asks: "Does the forward, driver-link part of the (501 87 53-01) linkage lie in the groove (slot) shown in the side-cover panel (530 03 75-47), where it is held by (and able to pivot about) the pin (720 87 543-01)? And (if so) does the (what seems to be a metal) spring (501 87 47-01) then sit "saddled" over the forward end and projecting tang of the driver link, such that the tang sticks up and through the bifurcation slot in the spring? (MetalSmith then deduces...)
    • (2) If so, then I envision that [some part of the?] the spring (530 01 59-10) must sit underneath the driver link (with tang) portion of linkage-and-spring-plunger assembly 501 87 53-01) [as well as underneath the 720 12 33-00 "fastener-&-pivot pin???], lifting [holding] it up [and...???]. Then, as brake handle is moved (back and forth), the pin [the little bolt] (501 87 49-01) contacts and glides (all the while pressing against 501 87 47-01 spring tension) on the upper surface of the drive-link part of 501 87 53-01—something like a lifter riding over cam & lobe (except the opposite in terms of force and motion-change application).
    • (3)
    • (4) Therefore, when the brake handle is pulled (rearward towards brake-off/anti-kickback-armed), the 501 87 49-01 bolt, riding (&or rolling) atop the drive link [and 501 87 47-01 spring???] pushes back and against the trapezoid-shaped projection on the drive link, forcing the drive link (along with articulating link and spring plunger) rearward towards the brake spring and, at the same time, compressing the spring (501 87 54-01) and opening the brake binder band loop to release the clutch-brake drum [as described earlier]. Then, at that point, as spring 501 87 54-01 reaches maximum compression, and as the binder (band) loop is forced to maximum opening (to maximum clearance from the drum), the little bolt (501 87 49-01) approaches and then slips into the notch, the detent, in the (metal) spring 501 87 54-01 501 87 47-01, where it is captured. ...so that, captivated in the detent under 501 87 47-01 spring tension, the entire linkage assembly, helical brake compression spring, and binder band is (are) held in place—in brake-released configuration—until the brake handle is pushed forward or kickback tripping occurs. ...in which case, forward motion (or relative forward momentum) of the brake handle, and of the little bolt (501 87 49-01), overcomes tension of the 501 87 4701 spring, permitting the little bolt to move forward and out of captivation in the detent...after which the strong helical brake spring "takes over," driving the linkage (to collapse) and the upper brake band end forward, until the binder loop is contracted fully against the drum, and the chain-drive sprocket is stopped." [Respondent CA adds the following which was not stated (but also probably not overlooked) by MetalSmith:]
    • (5) Following MetalSmith's perceptive reasoning, it also appears that whenever the little bolt is released from "detention" in the bifurcated spring,
      • (a) it is then free to be driven forward (under forward brake handle pressure, kickback-dislodged hand impetus, or reactive kickback inertia) to the point at which, sliding along atop the linkage assembly drive link (and atop the relaxing bifurcated spring on either side), it encounters the drive link's upward projecting tang.
      • (b) At this point, continuing forward brake handle pressure( or, alternatively, coordinated or independent impetus provided by the relaxing bifurcated spring[?]) causes the little bolt, in cam- & cam-follower-like manner, to slide forward (seemingly up) onto the tang, pressing it downward,
        • (i) causing the drive link to pivot about its mounting pin, and
        • (ii) lifting the far (rear) end of the drive link upward—
          • 1. which, in turn, lifts upward ("deflectingly") on the connected near end of the linkage assembly's articulating link—
          • 2. which, in turn, permits the helical spring to expand forcibly, during which time
            • a. it causes the "spring plunger" to force the brake binder loop closed, and
            • b. (possibly) also adds impetus to forward brake handle motion
              • i. via forces transferred through the linkage and little bolt...
              • ii. in tandem with impetus/momentum provided by the relaxing bifurcated spring.
      • (c) (Note: How the composite (Z-shaped) torsion spring "plays" into all this—to add a component of force or to restrain/moderate/manage forces, is an issue still yet to be resolved—an issue, the resolution of which, is apt to bring needed insight into how the torsion spring needs to be installed. )
    • (6) CA responds: Although I am not clear about how (and what part of) the composite spring "lifts up" or holds up the drive link in the linkage assembly, or to what precise purpose..., the ii)(2) & (3) description of the "basic brake actuation/release" dynamics, if interpreted correctly, leaves little or no visible room (vis-a-vis the illustration) for dispute; and I would say at this point that it is correct insofar as it goes, but possible not a fully-comprehensive description—in part because it does not take into full account the full range of potential/kinetic force vectors—the freedom of motion to impel or damper—of the composite spring. However, leaving aside the issue of the composite spring for the moment (for further discussion later on), I do find reason, based in part on observations while handling the brake assembly, to take mild exception (though not meant to disprove...) regarding a some aspects of brake functioning and component interfaces. First...
      • (a) Though the detent in the bifurcated spring could well play a role in captivating the overall mechanism in brake release/kickback-safe-armed position, I do not think it could do so by itself.
        • (i) ...because the helical, binder strap actuation spring stores so much potential force when compressed (in brake release mode), that it would, I sense, readily overpower any resistance offered by the detent in captivating the drive-link actuation bolt (and brake handle).
        • (ii) Even if the bifurcated spring could assume a shape so re-curved that the bolt could not "escape" from its detent, the force applied by the helical spring would be so great as to leave the bifurcated spring permanently "sprung," permanently bent (or deformed) beyond...recovery. As second "proof" that the bifurcated spring cannot act alone...
      • (b) If the bifurcated spring and detent were sufficiently strong and resistive, respectively, so as to prevent expansion of the helical spring, then the brake handle ought to be similarly resistant, after accounting for leverage, to being pushed or impelled forward to bind the clutch drum and stop the chain drive sprocket. To my recall, inordinate force was never required to push the brake handle for parking the chain. And, high resistance to brake application would not, seems to me, bode well for reliable anti-kickback functioning. So, if bifurcated spring cannot do the trick (of captivating the compressed brake spring) alone, what then? Here's a possibility based on direct examination...and which illustrated in the pic below.
        • (i) The red arrows point to depictions of a recess in the "link articulation" area of the sprocket cover; the red arrow in the line drawing also depicts spring release force vector as the spring pushes "thru" the link articulation as brake handle forward pressure moves the link assembly upward &or forward. In the depicted, spring-released, brake-applied configuration (photo) the link is deflected and (probably) does not "reach" into the recess—and it doesn't need to since the limit of travel of the spring and articulating link in the brake applied configuration is dictated by the diameter ( less external and internal wear, respectively) of the drum and contracted binder loop.
        • (ii) If, however, the spring is fully compressed (brake handle drawn fully back...and little bolt captivated in detent as described above), and if a mechanism to prevent the linkage from collapsing is functioning, then the forward end of the double-articulating link (its rear end only is visible shown in the photo) just might travel forward, and even a little downward, and lodge in the recess—the more firmly the( slightly released) spring presses, the more tightly the link lodges...unless another force (vector) is applied which dislodges ts just at the time the brake is attempted to be released, either by moving or striking the brake handle forward, or by inertial "triggering" of the emergency brake actuation mechanism. However, this (maybe) presents a secondary problem:
          • 1. In suggesting that the brake handle would need to be pulled slightly (to dislodge the link) before pushing (to apply the binder). I do not remember this being the case—and it doesn't make sense in the context of kickback braking. So,
          • 2. It seems reasonable to surmise that something else in the assembly and component interfaces, something probably including the composite spring, working in tandem..., is able apply just the momentary force needed to dislodge the link so that the its forward end is free to deflect and travel upward (as if wending around the upper aspect of the recess) while the binder tightens down.
            • a. One possibility might be that the rear of the drive link, when levered upward by downward force on its forward tang, provides the "lift" needed to dislodge the articulating link.
            • b. Another...that some part of the composite spring is able to help lift or push rearward on the articulating link to help dislodge it (?).
            • c. Coincidentally, a couple of mock assembly "experiments" I did might give a clue about how the composite might function, under the recess-capture "theory" in (ii, or otherwise, to help "operate" the linkage correctly:
              • i. When I assembled (as per above) leaving both the helical and the composite springs un-installed (...no energy potential except in the bifurcated spring), the articulating link was lifted readily when moving the handle forward to contract the binder. (The chain brake seemed to function nominally through both ranges of motion.) However
              • ii. When the chain brake is assembled with only the composite spring left out (with helical spring present), the articulating link will not "stiffen" in straight alignment when brake handle is pulled to release binder; instead, as shown in the photo, the articulating link flexes (seemingly even more, as if trying to push angularly downward towards and below the recess...until the brake handle is stopped short of its full range of rearward (brake release) travel (as shown below and in the early-posted photos in these discussions. This malfunction when the composite spring suggests that it is a key to making the linkage assembly links articulate correctly in both compression and compression release modes of brake handle operation.
  • iii) Metal Smith concludes, saying:
    • (1) The way I [MetalSmith] would probably assemble it would involve leaving pin (little bolt 501 87 49-01) out until everything else is assembled together; then...
    • (2) While looking through the (bolt insertion) pin holes in the lower handle, I would pivot the handle slightly, left/right, until the near and far bolt holes lined up just above the drive link and just rearward of (towards the brake spring from) the drive link tang, and
    • (3) Then push the bolt through and fasten with spring clip of the other side.
    • (4) Note that during and upon completing little bolt installation, the drive link should be in or near the brake applied/handle forward-most/drive-link-tang-depressed position.
    • (5) Cowanon: Again you (MetalSmith) have scoped out the task thoroughly; and it does seem that the little bolt is one "keystone" holding the interfaced brake binder "drive chain) components together in correct alignment...with one possible exception...
      • (a) That possibility being that inserting the handle pivot pin (just below the little bolt) next after the little bolt might be an approach that would make it easier to attain alignments when inserting the little bolt—because you'd have greater handle mobility for adjusting the alignment (?). I don't know because I did not test.... But inserting the little bolt pin before the handle pivot pin might even be necessary if composite spring insertion needs to be done (perhaps with special tool) from the handle bottom only after the linkage is aligned and secured. As said, I don't know for suer... but I do know that the way describe in (1) thru (4) does work, but is very difficult and requires much patience (and probably lots of swearing during learning curve). I also know, from not so pleasant experience that...
      • (b) the absolute last thing(s) to be installed should always be the helical brake spring (and spring cover and cover screws) Otherwise the spring, if not installed last, will apply so much pressure to the linkage that both the alignment manipulation of the handle, and the attempt to view the pathway and insert the little bolt will be exceedingly difficult...and might even "provoke" damage or pinching. My experience was that the instant you got one thing aligned, or the little bolt started, something would always move(because you didn't have enough hands (or strength/leverage) and you'd have to keep starting over; or the helical spring would fly out under great force, at risk of being lost or causing injury. (Note: this seems to be the only thing about chain brake assembly that Husqvarna knew about, so they get credit for being half right; but that's another story....)
      • (c) So, summarizing, we seem to be left with only a few uncertainties related to how the brake assembly goes together:
        • (i) Whether the little bolt actually goes over and slides on top of the bifurcated spring, or below and slide underneath.
        • (ii) How exactly does that composite spring fit and how does it interact dynamically with the other moving parts? Is it the component that makes the brake linkage work? Or does it serve a separate purpose of its own? Or both(?).
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#43

Husqv repair-Classif'n 5: Hardware...problem...12 ref O (actually 8)-Ron—

03/10/2008 9:51 AM

Classification 5 - Hardware interface/reassembly & setup problemPENDINGPOSTS

  • a) 12 ref O (actually 8)-Ron—1st part: agrees w/ Metalsmith, asks pics of pin mentioned in linked posting; thinks spring concentric w/pivot as shown in posted drawing and presents evidence.
    • i) Cowanon responds to 1st part of Ron's statement: The picture and explanation are provided below. Ron, please see answer in section d), below.
  • b) 12 ref O Ron— (2nd part)—agrees w/ Metalsmith, asks pics of links, thinks spring is concentric w/handle pivot...as per posted line drawing...
    • i) 14 rf 12-CowAnon—(already posted disagree idea of spring pivoting on handle pivot, more reply to Ron's 2nd assertion about Ron's description of "imprint" on handle pivot axis retainer nut: partial change of mind, correction of disagreement.
    • ii) Ron, here are two close-up pictorial views (same as above, and vertical-as-installed [inset]) where the owner manual's line drawing supposedly shows the composite spring's installed position...for which you claimed to find evidence. The "imprints" clock range position you mentioned is also indicated on both. Frankly, I just could not relate any artifacts on the handle axis nut (forget about Husqvarna's inept nomenclature-ing) to the "spring" (also a miss-nomenclature...as you'll soon see) as your post suggests. But, wait! I was looking at another chainsaw photo and... now I think I see it...let me point it out and add a pic below. (Be right back...) There, I amended the picture and posted it below.... And here's the other pic I was looking at as well....also with some additions. Ron, I now think you have scored a coup, and that all participants should immediately go back to post #12 and give you a GA Attaboy.
      • (1)

      • (2) It now appear my previous rebuttal might have been mistake (except the part about Husqvarna's inept drawing and part list nomenclature—and assembly break-down configuring as well); and that your observations are (almost) exactly correct—and, I've marked an additional "imprint" where the spring appears to have made contact...no, forget about that last statement and the black pointer and caption in the right-hand pic. Not only have you made an important discovery that explains why no amount of effort has succeeded in fitting the spring (back!) inside the handle; you have also, both, created and solved a heretofore unknown mystery! What I mean is, your observation has led to my uncovering the commission of a criminal act—one which I now am convinced is one of many such acts by the person/company that sold me the saw—and their modus operandi.... but I digress....
  • c) When I first was able to make out the markings in the picture, that decided me to pull out the saw and check first hand—remembering from earlier how difficult it would be to again re-assemble the brake assembly, I had deferred doing so until I could be reasonably confident of being able to reassembly it correctly...based on expertise from these CR4 discussions. It was when looking at the picture on the right (above) and at the saw (and both before and after re-disassembling the chain brake assembly (pic, bottom) that previously unseen picture (and possibly the answer to the main question) began to emerge:
    • i) After disassembling the chain brake assembly—this time removing the brake prime mover, the helical spring, first—yes, it made both disassembly and later reassembly much easier—I was able to attempt to match the larger helix of the composite "spring" (now recognized as a misnomer, as you will see....) to the imprints markings on the saw handle pivot axis nut (and to the Husq' drawing depiction):
      • (1) To my surprise the helix did not seem to match well to the markings on the handle axis pivot nut itself.
      • (2) Curiously, the smaller turn in the spring seemed a better dimensional match...so, did this mean the nut was misplaced in the drawing? To find out...
    • ii) I began looking at the circular recess molded into the side cover of the saw itself (see picture above)—the recess which appeared not to have any function...other than to accommodate something of similar shape as the "composite" spring, either one of its helix turnings or its bend.
      • (1) The "larger" helix proved to be a good match, the bend almost as good.
      • (2) This still could not explain how the spring could fit there and also function dynamically with brake operation; i.e., why it was depicted as it was in the mfr drawing.
      • (3) It was at this time that it occurred to me that the imprint markings, if not consistent with the spring having been in full contact (there you'd expect a full-circle imprint, not partial imprints), might be consistent if the spring and nut had contacted each other only at an angle—such as if the spring (and its helix turning) had been leaning towards or away from the brake handle (nut)—such as if the spring was in contact, both, with main saw and handle nut...in such a way as to prevent it from "escaping" and being lost, even under high vibration saw operation.
        • (a) I decided to mock up the fully assembled saw configuration and see if a sensible spring placement could be found when all saw "subassemblies" were joined...and how the spring, if external on the chain brake assembly, might be retained to prevent its loss.
          • (i) I assembled a "chain brake assembly" using only the handle (shell), the cover with band (shell), the little brake actuation/release bolt, and a key from my multi-hex-key tool (it was handy, having been previously used to remove the brake handle) to "stand in" for the three-part brake axis pivot.
          • (ii) Fastening the mock brake assembly to the saw (with saw chain bar) mounting/tension-setting nuts, I then tried every conceivable spring positioning I could think of to find a "best" fit for the spring...and some way to "mount" it so it stayed in place.
            • 1. At length I was able to find a "best fit"... one in which the spring could be (more or less) securely "fastened" in place...but to what purpose? That remained a mystery.
            • 2. And the other end of the spring—where to "attach" it and how the spring might function.... at this point I decided to put it aside and revisit figuring out about the chain brake assembly...this time without the composite spring...if could be assembled to work.
      • (4) Since the assembled brake assembly had been made to work previously—after a fashion—to close (but not to open) the binder strap when the heavy-force helical spring was present, I decided to (try again) to change the only thing that can be changed: instead of atop the bifurcated spring I inserted the little brake linkage actuation bolt so that it would travel beneath the bifurcated spring when the handle is moved.
        • (a) Previously it had been virtually impossible to do it this way with the helical spring installed.
        • (b) Without the helical spring in place, it proved not only possible but fairly easy—even easier than installing the bolt above the bifurcated spring!
        • (c) Only one hitch was encountered...there were two positions (or ranges) along the bifurcated spring at which the bolt could be inserted, one which would and one which would permit full movement of the brake handle (more about that in a full procedure I intend to post after the end of this discussion, but for now...)
        • (d) Once all chain brake assembly components, except the helical spring and spring cover, were installed (with bolt in proper position):
          • (i) Testing showed the assembly to be working as designed through its entire motion range, for both opening and closing the binder.
          • (ii) The so-called "pop" (at the transition from brake-on to brake-released was also "observed"—the "pop" (with its connotation as something exploding or breaking [no pun] is better described in this case as a (palpable) barely audible "jolt"...or "bump"...but this could change with helical spring installed.
          • (iii) After repeated brake/un-brake trials it was decided to retry...ii)(3)(a)... but, before that, the finger-tight assembled brake assembly, set at brake off (handle back) was observed to be readily and easily fitted (and secured with bar mounting nuts), with no binder-strap-clutch-drum interference, at its "installed" position on the saw.
          • (iv) (The decision was made at about this time to reserve discussion about how the spring got inside the handle to begin with, for another, potentially off-topic, posting. )
          • (v) (The next test—repeating above steps ii)(3)(a)(i) & (ii) would finally reveal the almost certain "true" purpose and function of the (heretofore) "composite" (etc.) spring...and more errors in the mfr's manual's descriptive and pictorial documentation of the saw—and, inferentially, how it was these errors that led to all problems to begin with...
    • iii) The below photo shots of the trial "installation" of chain brake assembly on chain saw shows what appears to be the "official" correct fit. (Taken with only a flashlight beam to illuminate it, I have added pointers to indicate the (formerly called) spring in its nearly hidden position behind the "side cover."
      • (1)

      • (2) Note that in this position the "spring-like" object (inset) appears to serve the sole function of supporting the saw top cover—as an adjunct to the opposite side (shown as view A) and probably functions:
        • (a) To brace the otherwise unsupported right side of top cover.
        • (b) To prevent possible distortion of top cover induced by heat from engine/engine exhaust.
        • (c) As a vibration damper—to alleviate loosening of (say) the bar-mount/chain-adjust nuts, chain-tensioner, and such....
        • (d) Note also the errors in the mfrs drawing and parts list(s):
          • (i) Where the spring-like object is depicted 90° out of rotation, and backwards;
          • (ii) Where the same is depicted in the wrong drawing;
          • (iii) Where the part number prefix (symbolizing higher assembly) is ambiguous;
          • (iv) Where an accurate nomenclature would have read something like: "spring-form brace (or) strut...or simply, (say) brace [catalog format: brace, springform (top-cover-support)]. The original name being wrong in that:
            • 1. "Spring" has not relation to actual function—hence leads to confusion.
            • 2. It is not properly a "spring"...in that the term, spring, is reserved only to an item that functions as a spring (it serves to push something (by expanding from compression), pull something (by retracting from extension), or turn something (by twisting or untwisting)...the brace (as it shall henceforth be called) does none of these.
    • iv) So there it is: the original question now appears to be resolved; but is it actually resolved?
      • (1) The next step to find out will be to dismantle then re-assemble the chain brake assembly with the helical binder-actuation spring—which might entail fabrication of a tool as suggested by another (Justan as U recall) ; remount the assembly with brace properly installed; and restart and test both the chain brake and the saw.
      • (2) Also to be done is posting a reply to Just an Engineer's entry.
      • (3) I will post the final results (except for the accurate teardown and reassembly procedure) after completing (1) and (2). PLEASE, stand by.
  • d) Ron, you asked me to point out the "pin" referred to in the following linked passage:
    • (i) "I think it's a bad design on the post supporting the chain brake spring lever. ...(a little more than 1/8") pin ...only press-fitted into the aluminum sprocket cover. Impossible to reset this device if you remove the cover while the chain brake lever is engaged. I broke it...trying to compress the spring to refit the cover. ...I...modified it the way I think the original designers should have made it, by drilling out the broken shaft hinge [?] post, and tapping a 1/4 x 20 thread for a machine screw... ...hardened metal three-spoked spring lever had to be drilled to hinge on the new...screw. ...fun. Then...assembled, securing the screw on...thread side with a lock washer and nut on the new hole that penetrated the case, on the outside of the case."
    • (ii) I pointed out the (what I sense to be) the corresponding pin above, in the lower-right-most frame in the picture at b)ii)(1)...the subject pin (elsewhere called "bolt" in these discussions) is circled in yellow. However, I note that the quoted speaker refers to a metal cover (quite likely on a metal saw), from which can be inferred that the saw might be much older, and possibly with chain brake assembly of different design and function. Naturally, we would think of newer, plastic-housed chain brake assemblies as mere derivatives (clones insofar as plasti-form fabricating allows) of metallic-housed predecessors. However this is something we (or at least I) cannot take for granted. As to the metal saw's applicability to this discussion, in view of the "discoveries" mentioned above, any similarity might now be a moot point. However...
    • (iii) It is interesting to see how that Husqvarna saw owner, too, appears to have gotten tangled up a bit by the poor nomenclature choices used in Husqvarna manuals—apparently some things never change.
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#52
In reply to #43

Re: wording correction

03/11/2008 8:40 AM

Correction in antecedent post:

c)i)(1) To my surprise the >larger< helix >in the "composite" spring< did not seem to match well to the markings on the handle axis pivot nut itself.

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#44

Husqv repair-Classif'n 5: Hardware...problem...30 rf O (and 8)..Just an Engineer

03/10/2008 10:35 AM

Classification 5 - Hardware interface/reassembly & setup problem

30 rf O (and 8 metalsmith)-Just an Engineer—good ideas about actual assembly

  • i) Prior answer: 31 rf O/all-CowAnon—Like some prior posts, I find post #30 to be uncanny (that is to say...on the mark based on my own experiences attempting repairs) in many ways....
  • ii) Updated CA response follows (Part 1: General reply, Part 2 specific comments.)
  • General
  • iii) Justan, it is unmistakably clear from your post that we have together, both been there; done that...and with virtually the same machine; which is good—you will not take anything further below in other that the helpful spirit intended. Your saw, as I'm led to understand, is essentially a more recent derivative of the Series 36/41 line—note the model no. similarity when the (mfr-added-for-PN- churning) third digit is ignored. Looking at the your saw (pictured below), and seeing that it, too, uses the single-pivot-hinge chain brake assembly, it is likely that, except for tweaking stock bar & chain sizes (36" to 35", 41" to 42") the two saws are virtually if not exactly the same.
  • iv)
  • Specific
  • v) There were a couple of things...perhaps you've already discovered if you have read my recent replies above.
    • (1) First, your mention of "'toothed gears'" visible from above the handle pivot housing subassembly. This got me to wondering if Husq. had actually redesigned...with some kind of gearing arrangement. (Not to make it any more reliable, mind you, but to simply make it easier to factory assemble using semi-skilled labor...one of the chief engineering functions in consumer tool innovation these days, it seems. However, if it was redesigned to correct a persistent warranty issue...then that would mean that Husq.'s repeated claims about not having a problem with the chain brake assembly were probably out-and-out deceits.) But for now I'm assuming that was just your way of describing what shows through the handle opening...and that we are speaking about the exact same chain brake assembly for all intents and purposes.
    • (2) The second thing is your description of doing the assembly and reassembly. Seems to me your experience—because you were able to get it together by hook or crook the first time—and unlike me who has had to really work at it—in a sense deprived you of discovering a basic key to easier disassembly and reassembly (I discussed this, too, earlier on in this forum.) The key is:
      • (a) The main brake band driver spring always (after removing its cover) comes out first and goes back in last. (Yes, it is true, this part is quite difficult...there's practically no way to get both good leverage and keep things from wanting to become airborne under the great spring pressure. And how to both design and fabricate a [very thin-gauge and yet very high strength tool that will hold the spring compressed and yet still slip the spring in place where there is almost zero clearances...that's a real mind bender. Anyway, not having to fight the helical spring makes getting the internal components lined up in the handle a whole lot easier.
      • (b) The order of assembly...I found that, although it seems logical to install handle pivot components (screw, grommet, and internally-threaded screw-receiving grommet) before the brake actuator pin just above, it is far easier to install the pin—even the retainer clip—first, then the handle pivot components. You have much more latitude for moving the handle to get things lined up for inserting the pin; and it's easier to see what you're doing—no stabbing blindly. Of course—and you might have experienced this with or without realizing—this approach is practically impossible if the helical spring was not removed—which, by your description seems to have been the case with you: where the handle pivot had to be secured to have any hope of properly inserting the brake actuator 'pin."
      • (c) With these things in mind, I have reposted your helpful information below showing what I understood you to be saying...and how it fits with what has been discussed elsewhere...
  • vi) J-a-E's quote w/ CA response insertions:
    • (1) Didn't read the whole item, but "Yep, been there done that." [Maybe the wrong way, just like me, judging by what's below... J ] The answer was simple (after about five cups of coffee and a "stop and think" moment.) (HUSKVARNA 350) [So Coffee is the answer!? J]
    • (2) What...happened...after removing...[side] cover to fit a new chain, in my zeal to clean away all the muck [zeal?! For muckraking?] , I had inadvertently activated the "anti kickback" lock ]brake binder clenched] and as in your pictures, the "band" was...clamped down [contracted].
    • (3) If you look where the handle fits into the cover[lower, pivot-housing part of the brake/cover assembly], there iscould be seen (in my case) [what appeared to be?] a three toothed "gear" that allowed [caused} the handle [, when moved,] to activate [to contract or expand] the band. Refer to your three "real life" images. What has happened is, the chain brake [brake's band actuator mechanism] has been activated [actuated, and has become jambed in band-closed, brake-applied configuration]. You need to [correct this in order to] de-activate[be able to return the brake to un-actuated position] this. (You will know when this has been achieved as the band will be back fully expanded and] snug against the outsideinside surface of the [circular, band-corralling "fence" molded into the] plastic recess [chain brake/side cover fixture].
    • (4) This is NOT an easy task with the unit dismantled, but can be done. You need to:
      • (a) 1) Find in the mechanism where the handle would normally be positioned.
      • (b) 2) Determine which direction it needs to go to "release" the brake
      • (c) 3) develop a "tool" to do this [to do what?? See above about spring handling tool.].
      • (d) A) BE VERY CAREFUL from here on. The device has a cam and VERY strong springs and can jam fingers or send a tool across the room.
      • (e) 4) Cause the device to rotate and [Use the handle to release the brake [brake spring??]. (You will see the "long spring" relax to a closer coil spacing.) [??? The helical (compression-type) spring can only "relax" (at the same time applying closing/clenching pressure to the band) to wider coil spacing...which is what it does when the handle moves forward. The action is accomplished by the handle applying leverage (direction- reversing central fulcrum position—where linkage attachment/ pivot point is the fulcrum) which causes the brake apply/release linkage, nearest its attachment to the spring, to deflect upward so that the spring (now) has room to extend...and (by extending/relaxing) to also pull/force the brake-binder band towards closed/clenched. Conversely, when brake is fully released (handle rearward, binder strap loop fully opened), the helical binder-strap actuator spring is at maximum compression (armed for anti-kickback service), with least spacing between coils.] [A good way to conceive the "cam and cam-follower" analogy is to think of "it," not as cam (lobe) and cam follower per-se but, rather, as a cam that has been turned inside-out, such that the cam follower is...following along the cam and over the cam lobes from inside the cam...a hollowed out cam. What ever rotational-to-linear direction change might have been caused with "regular" cam and follower, will be the opposite with this, inside-out cam and follower setup.]
      • (f) [Note:] The difficulty...comes from...lack of [easily attainable] leverage available when as compared to [when] using [able to grasp] the forearm guard [(wrap-around front saw handle)] withwhen the saw [is] fully assembled.
      • (g) My HUSKY has had a few minor issues, but is now around 400 hours use making fence posts, firewood, sheds (from timber cut on the property) heavy duty furniture, clearing storm debris and other general farm use. ...Hope this has helped. Just and Engineer from the land down under... Score 1 for Good Answer
  • vii) Ron, I stated in an earlier reply that, thanks to everyone here, I think we've solved the problem. But there is one more step...checking the assembly with the brake-actuation spring installed—so far I've only operated the brake with the spring not installed. I will report back when this test is able to be done to confirm the problems have all been resolved. After that I hope to generate a complete and accurate chain-brake assembly tear-down and reassembly procedure and publish it here...so others don't get snared like I did, looking endlessly for information, or relying on a seemingly clueless manufacturer.
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#50
In reply to #44

Re: Husqv repair-Classif'n 5: faux pas in #44

03/11/2008 7:45 AM

From previous post, #44: "...vii) 'RonJustan, I stated in an earlier reply that, thanks to everyone ....'"

Dear Just an Engineer from a land down under,

Please accept sincere apology for mental error indicated in excerpt above.

Regards,

CA (from a land up over and to the right [...from down under])

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Anonymous Poster
#53

Re: Husqvarna's built-in chain brake problem-repair how-to

03/27/2008 5:32 PM

I had this same exact problem with my husky 41. Couldn't get the darn brake to work, no matter how I assembled it. I am pretty good mechanically (I am an engineer), but just couldn't get this to work right. After numerous tries, I finally removed the goofy wire spring (part #530 01 59-10), and then cut 3 or 4 loops off of the spring coil with my dremel. The brake now works great - extremely reliable!

Hope this helps anyone who may be in a similar boat.

Brian

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#54
In reply to #53

Re: Husqvarna's built-in chain brake problem-repair how-to

03/29/2008 11:23 PM

Hello, Brian

Working with the others I have found the solution to the problem with the series 36/41 saws, and will be posting it in detail soon.

I do not recommend the alterations you suggest and think you will soon agree they are not really necessary. The spring you specified—actually, it is not really a spring at all, functionally speaking—serves a much different function than seems to be indicated by the drawing; it was actually depicted on the wrong drawing of the saw!

So here's a sneak preview of the solution to come. Think of the item not as a spring but, rather, as a brace: specifically, the top cover brace. Its function, because the right-hand side of the top cover (unlike the opposite side) is cut out, seems to be solely to provide support and stability--perhaps also it helps prevent sagging due to heat from the engine.

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#55

Re: Husqvarna's built-in chain brake problem-repair how-to

03/31/2008 12:04 PM

this might be a problem with a fairly new pouland..noticed the clutch free spin right before the no start situation...a little tension on the chain will prevent the start..I'll see thanks steve

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#56
In reply to #55

Re: Husqvarna's built-in chain brake problem-repair how-to

03/31/2008 2:24 PM

Guest Steve,

Not sure exactly what you're saying...

By "clutch free spin," do you mean that the chain stalls (giving the sense that the clutch is not grabbing...is free-spinning) while cutting? (Could it be that the binder is not released totally?)

And that, right afterwards (after that "free-spin" happens), you can't get the engine to fire up and run?

About "a little tension on the chain will prevent the start"...

Start of what? Start of the perceived "clutch free-spin problem? Starting of the engine? (There should never be undue tension on chain during engine start. But chain tension will not affect a Husqvana's engine start.)

What is a little tension (as opposed to more than little tension)? Moving the chain by hand prior to starting? Too-tight chain? Attempting to (re)start engine with bar and chain in mid cut? Over-opening throttle (over revving) during engine start? Adjusting chain tension before engine start attempt? Other?

Steve, if chain stalling/slippage is what you've described, you might want to check the drive sprocket for sheared off cogs. And the chain lubricator pump/outlet/oil supply...as well as bar sprocket if the Poulan is so equipped.

Clutch slippage on my (above pictured Husq'y) would become evident, not as chain stalling--or even, necessarily, as noticeable chain slowing--but, rather, when smoke began issuing from the chain drive area; but things might be different with your Poulan.

I recommend for you to post your problem as a new discussion on the board...that will help me keep this (Husqvarna based) discussion easier to follow and moderate. Likewise you will be better able to respond to and moderate feedback regarding your Poulan based problem.

Hope the above is helpful for you. Feed free to send me PM (you'll need to sign up) if that will help.

CA

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#57

Husqv repair-Classif'n 5: Hardware problem solution for Hooskie chainbrake

04/01/2008 6:22 PM

Introduction: Following is an all-pictorial solution to discussion question, commencing with the "engine won't rev" condition and including teardown to and disassembly, lubrication, and reassembly of the chain brake assembly. Due to web site (page) restriction, the procedure continues in the subsequent posting. Remounting of the chain brake assembly is not covered here, but can be provided to interested members upon PM request. The pictorial procedure shown here is a part of a comprehensive chainsaw power takeoff fixtures maintenance procedure, with complete text and pictures, developed for subject chainsaw in the absence of adequate mfr documentation. Complete text and pictorial procedure is also available on request from interested CR4 members. Procedure which follows includes text notes/warnings where applicable.

1 [Start by pulling to open brake binder so brake assembly can be removed from saw.]

Note: Brake handle (hand grip) offers resistance, and noise will be heard, as brake-actuation linkage is forced into (by pulling hand grip) and out of (by pushing hand grip), drive-sprocket-binder's release-locked and release-unlocked positions, respectively: characteristically, brake handle "clacks" back and "pops" forward. Due to brake spring resistance, considerable comparative "pull" force on hand grip is required to lock (internal) brake-actuation linkage in binder-released configuration. Position of brake handle and status of sprocket binder can be determined by direction of handle movement which offers no resistance; where binder released when no resistance to handle pull; and binder applied when no resistance to handle push.

2

3

4

[5, 6 - Bar and chain removal, and bar, chain, oiler, spocket maintenance service procedures omitted. Chain brake disassembly...lubrication...reassembly starts next.]

7 (Note: loosen sightly but don't remove upper right cover hold-down screw as pictured at right.)

Warning: Helical brake spring is under high pressure. When removing, keep pressure applied on spring-retainer cover to prevent sudden and uncontrolled spring expansion prior to removal. Eye Protection Recommended..

8 (Note that spring cover is held down to restrict spring during removal.)

9

10

Note: There are two "pivot" components in the handle: a socket-head axis screw with smooth-bore & female-threaded-bore grommets which form the brake handle hinge; and, above that, a bolt (pin) attached with circlip, which assists in driving brake-actuation linkage between "brake-applied" and "brake-release-locked" (kickback-reaction-"armed") positions. Unless renewing, removal of bolt (pin) and circlip is unnecessary (not recommended) and may be excluded. If necessary to renew...best if bolt (pin) and circlip are removed/replaced only after brake handle component is detached from base part of chain brake assembly.

11 (Loosen and strike socket head screw to dislodge grommet on opposite side.)

12 (Invert and strike on opposite side to dislodge grommet on screwhead side.)

[Continues in next message. Please hold replies 'til rest of procedure is posted, Thank you.]

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#58

Part 2 of Husqv repair-: Hardware problem solution for Hooskie chainbrake

04/01/2008 8:00 PM

[Continued from previous post]

13 (Lubrication points: Oil on left, chain lube oil on right)

14

15 Note that brake binder control below is in in brake-binder-released/kickback-safe-armed configuration.

16 Note: Tool is inserted temporarily to serve as handle pivot in order to test and ensure correct alignment prior to installation of permanent handle attachment and pivot hardware. Be sure brake handle/linkage is placed in handle-forward/brake binder applied/clenched orientation before proceeding with subsequent brake spring installation.

17 (At right, install one screw only.)

18 (Below: loosen scew only enough to permit rotation of cover. Keep pressure on cover while installing brake spring.)

Note: Attempting to install helical brake spring with brake handle in rearward (brake-binder-released/kick-back-reaction-armed) will require greatly increased spring insertion force and is not recommended.

Warning: Attempting to install brake spring with brake handle not in forward-most (brake-applied) position increases likelihood of injury caused by spring/finger/tool slippage or by sudden release of brake chain linkage from "kickback-armed-and-locked" state. Install spring only with brake in neutral, brake-applied brake handle position.

19 (Note that in left picture thumb holding down cover is not shown...it had to help with snapping photo shot. At right, lever pivoting on projection below provides leverage to squeeze spring into channel. Note binder strap is contracted.)

20

21 Place chain brake assembly partially onto saw's mounting studs and install mounting nuts finger tight...so enough leverage is available to pull back brake handle and open brake binder to enable complete chain brake seating & installation on saw, along with other maintenance service...

22 (Chain brake assembly verification, bar & chain mounting and adjustment steps are omitted...please inquire if interested.)

End of chain brake service procedure.

Chainsaw photoart shown below.

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#103
In reply to #58

Re: Part 2 of Husqv repair-: Hardware problem solution for Hooskie chainbrake

09/07/2012 6:26 PM

Thank you for your post and images. Major Thanks! Have owned my Husqvarna 55 since picking up online about eight (8 years) years back.... Unknowing about the brake anomaly, left it sitting at idle and turned around to find it smoking and the side totally melted? Took it apart after cooling off and simply ordered another Husqvarna brake/ clutch side assay from Jacks Small Engine. Fast shipment and quality parts... but after reassembly... having problem(s) with allowing the saw to turn when disengaged. Put this saw aside 8 years ago with 2.4 hours on it before finding your posts. Will keep my three Stihl MS880 Magnums for backup just in case.... but loved my Husqvarna 55 Rancher ;o)~ Now Thanks to these POSTS... back into taking it apart and some old fashion diagnostics and trying to get this Husqvarna Rancher55 at my side 55 feet in an ol Florida Oak helping this old Arborist again. Wish me luck and Thanks to everyone! Am a Physics "Nerd with Phd" in same... but prefer to work at top of the world in any tree that will support me and my old bones and muscles can climb!

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Anonymous Poster
#59

Re: Husqvarna's built-in chain brake problem-repair how-to

09/24/2008 8:22 AM

Here's an email I wrote this morning. I think y'all will find it funny!

"I used ****'s saw during deer season the same year he died. When I went to use it, it cranked ok... but the chain wouldn't spin! ...I just put it to the side and used my little saw. When I got home, I checked it out. It has a "clutch brake" which is part of the whole side cover that goes over the clutch, sprocket, and the bow. Well... the brake was engaged... rapping a circular steel band around the clutch very tightly... so the clutch couldn't turn (which drives the cutting chain). It was a good invention, because if you're cutting wood and the saw kicks back at you, the clutch brake will engage and stop that chain from turning. Well... I didn't see any way to get it un-braked (unlocked). So, I figured that it must be broke. I took it apart, and couldn't find anything wrong with it... other than it was stuck in the locked position. So.. I just took out a long heavy spring in it (which was causing the pressure on the steel band around the clutch) and put it back together. I used it a couple of times after that, but it made for a very dangerous situation in that the chain would still turn even when the saw was idleing. I was just very careful with it. I figured I'd get somebody to work on it one day. Well... when I went to use it the other day, it wouldn't crank. So, I started looking for a carburetor for it on the internet. I found carbs for it from $30.00 (generic brand) to $110.00 (Husqvarna brand). I bought the $30 buck one! The same guy had generic clutch cover/brakes to fit this saw for 45 bucks! I says to myself... what a deal! The Husqvarna covers are $100 bucks! So, I go to put the new cover on the saw yesterday evening around 7:30 pm. It wouldn't go on. That same steel band wouldn't go over the clutch! So, I came in here... and started searching the internet for answers. Finally, I just gave up, and put the old one back on the thing. I wrote the guy I bought it from (an eBay store).. and told him that I couldn't get it unlocked. He hasn't wrote back yet. I told him to try another one before he sent it. lol Anyway... I just couldn't believe neither of those things would unlock. Maybe I wasn't pulling hard enough on the unlock handle. I started searching again on the internet about the problem. Finally, early this morning, I found a dude with the same problem... on some forum. The people replying to his thread kept telling him that he needed to pull back on the brake handle to get it unlocked. Well... he was like me! We done pulled on the damn thing! I thought I was pulling hard enough to break it! One last expert told him... look... here's what you do... and provided pictures on assembly and disassembly. It was the very last post on his thread at http://cr4.globalspec.com/thread/18020#comment187531 . If you want to see it... scroll all the way to the bottom of the thread until you see the pics. I decided about 2 hours ago... to put the new one back on there and pull that handle hard. I'd made up my mind that it was either going to unlock... or I was going to break the dang thing off! Guess what. It didn't break. It unlocked. lol So... that was a $45.00 lesson in chainsaws 101. lol I think it was money well spent! lol"

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#64
In reply to #59

Re: Husqvarna's built-in chain brake problem-repair how-to

06/23/2009 11:20 AM

I just bought a brand new Hooskie 61. Same thing....brake won't disengage. I took off the cover (carefully, because the drum was held tight), and found this forum. After reading ALL of these super-detailed posts (great!!), I thought I was going to have to open 'er up. Just as I picked up my tools, I saw the post from the guy who just PULLED HARDER. I did exactly that (with some fear that I might break the plastic handle) and, VIOLA!!!....it disengaged. Thanks to eveyone who posted on this thread.....you guys are awesome...soooo much appreciated.

Kevin

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#60

Re: Husqvarna's built-in chain brake problem-repair how-to

11/01/2008 10:50 PM

It appears from your photos that the trip link that is at the top of the activation spring at the bottom of the handle may be in the locked postion? If this occurs it will be too tight to put back together since it would be in the stopped position. Some how I would consider the idea of trying to pop that back out toward the outside of the case or remove it all and re postion it to the realesed postion? With that link tripped upward it is pulling on the tension spring that pulls on the clutch band.

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#61

Re: Husqvarna's built-in chain brake problem-repair how-to

11/21/2008 11:02 PM

I know this is an old post, but I just had the same problem and the answer given here is way wrong. Thought I should correct the error.

The hand guard spring (530015910) goes "inside" the hang guard, not on the outside as the post pictures (post 54 & 57) and parts drawing suggests. It is also not held in place with pins through either coil. Instead, the large coil is compressed and jambed to the end of the hollow hang guard where it contacts a plastic cross brace. A pin (530874901) goes in front of the small coil. This first picture shows the compressed spring as it is oriented inside the hand guard.

When assembled, the end tang of the small coil goes behind the pawl of the chain brake "thingy" (501875301). The end tang of the larger coil rests against one side of the bifurcated leaf spring (501874701).

When the brake is activated, the pawl rotates rearward (left in the picture) and compresses the large coil further. I believe the added spring force makes it a bit easier to release the brake. Misplacement of this spring may be why the original poster had difficulty releasing his brake.

In any case, the hand guard spring does NOT attach near the muffler as the post suggests.

I hope this helps someone in the future.

Barry

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#62
In reply to #61

Re: Husqvarna's built-in chain brake problem-repair how-to

01/29/2009 11:53 PM

I find it hilarious that engineers will overthink a thing to exhaustion and in the end create an incorrect conclusion. Thanks for a simple and straightforward post with excellent photos. The perfect example of "keep it simple" !

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#63
In reply to #62

Re: Husqvarna's built-in chain brake problem-repair how-to

01/30/2009 2:03 AM

Thank you. Glad I could help. In defense of the previous, and somewhat confused posters, this one had me scratching my head too.

Barry

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#75
In reply to #61

Re: Husqvarna's built-in chain brake problem-repair how-to

03/09/2010 4:42 PM

AT LAST, someone who knows my pain! Your explanation and pictures were succinct and to the point and I was finally able to assemble this darn brake. The only change I had to make was to position the spring below the upper pin. I tried it above, but the tang was not long enough to achieve the goal. This also explains why the spring just fell out while being disassembled. Please accept my heartfelt thanks. It took me two days of frustrating perusal of the entire internet to find your solution.

Kate

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#98
In reply to #61

Re: Husqvarna's built-in chain brake problem-repair how-to

11/27/2011 2:58 PM

Like everyone else I was stumped on this damned spring, I spent hours staring at a useless diagram provided by Husqvarna. It doesn't make any sense whatsoever. The brake wasn't working so I took it apart to see how it works (Dumb idea considering the information available on the subject) I knew it actuated the lever somehow but thanks to your thread Cowdoc it all fell into place and works very well.

Cheers

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Anonymous Poster
#65

Re: Husqvarna's built-in chain brake problem-repair how-to

07/15/2009 10:09 AM

I realize this is not a new thread and at the risk of flaming for not being a professional I'd like to offer this:

After reading through several suggestions I decided to re-assemble my 51 without bar and chain - loosely, obviously as the brake was locked. I figured I'd use the leverage of the saw to correct the brake position - gave it a good hard pull. It reset. I took the assembly off and re-assembled the saw with bar and chain. Everything is working fine.

I bought this saw 18 years ago and used it quite a bit back then - now it's once every couple of years - still starts right up and runs great - that's why us amateurs buy professional tools.

Thanks again for the thread - saved me $ and frustration.

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Anonymous Poster
#66

Re: Husqvarna's built-in chain brake problem-repair how-to

08/22/2009 2:05 PM

I have a husqy 235 small model saw. i had the brake assembly on mine lock up too. unknowingly how to fixed it i removed the chainbrake/clutch cover with it still in the locked posistion. long story short the only way to reassemble the chainbrake mechanism was to do so with the chain brake in the unlocked posistion which requires you compress the spring to its absiolute max which without some sort of special tools nearly impossible. I cut the last 2 rings of the spring off and it did the trick, the spirng seemed to stiff for the mechanism all along it would take a ton of force to get the brake on and off etc and byt shortening it just a tad it has worked even better.

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#88
In reply to #66

Re: Husqvarna's built-in chain brake problem-repair how-to

10/03/2010 2:48 PM

The idea of shortening the spring seems like a very bad idea. It is the spring and not the lever that applies the brake. The stronger the force exerted by the spring the quicker the brake release will stop the chain. With a weaker spring the mechanism still goes through the same motions but takes longer to activate. Perhaps rather than missing your face it may just nick your nose before stopping. I think you are trading ease of setting for less braking.

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Anonymous Poster
#67

Re: Husqvarna's built-in chain brake problem-repair how-to

09/27/2009 6:09 PM

For future consumers with this problem, I will actually try to help you instead of just throwing insults.

When I followed the directions for my never been used Huskavarna I had the same problem. When putting the chain on, the brake cover would not go back on properly because the brake was locked in the engaged position (unbeknownst to me, and certainly not anything you could figure out from the manual - which is terrible). I figured out that was the problem by coming to this forum.

I wound up putting the brake cover back on without a blade and though wobbly it gave me enough leverage that by standing on the handle, and with lots of muscle I was able to disengage the brake (pull the brake handle toward top handle - really hard). I then took the cover off, put my chain back on and voila - no problems fitting the cover back on and adjusting the tension. Now if only the manual had said, make sure the brake is disengaged before taking off the cover and actually discribed or had some marking on the saw as to how to be sure of this, all of our troubles may have been avoided.

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Anonymous Poster
#68

Re: Husqvarna's built-in chain brake problem-repair how-to

10/08/2009 2:20 PM

Hi, I just had a problem with my Husky 350 chain saw. Seemed like the chain brake was on, so after taking the chain cover off, cleaning every thing, I found that the cover would not go back on because the chain brake was on. So after trying every thing know to man to release it, I ended up taking the chain brake handle off the saw body, placing it in the grooves of the brake release and snapping it back to the off position. Then I reassembled the saw with no problems!!! Hope this helps a few saw owners out the. M.Dean B.C. Canada

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Anonymous Poster
#71

Re: Husqvarna's built-in chain brake problem-repair how-to

01/03/2010 4:01 AM

Very helpful thread even though simple procedure to fix problem not suggested till well into it - glad I persevered. I have a second-hand Husky 141 and the chain brake must have engaged since its last use. Didn't realise disengaging required so much force so removed clutch cover looking for another cause. Thanks to this thread I also put the clutch cover back on with nuts finger-tight without removing the chain bar and this gave enough leverage to disengage the brake. Cover got a bit distorted but has returned to its original shape. May help if second person can try to keep cover from bending. I agree the manual is deficient in not alerting the need to ensure brake disengaged before cover removed and describing how to ascertain this, as well as providing the solution if things go wrong.

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#72

Re: Husqvarna's built-in chain brake problem-repair how-to

01/04/2010 7:42 AM

hi i realise im very late in the day to this. however 1 hour ago my son and myself were getting logs. quite cold weather in n.ireland at min so when saw started cutting out i wasnt sure whether or not it was the icy timber(yes probably stupid) or that i had also noticed i accidently slightly touched brake. anyway saw stopped and refused to start. we took it into garage but i found great difficulty in removing cover which i had done numerous times before. anyway eventually got it off. cleaned everywhere then realised i was unable to place cover back on. not only that but a strange coil was probably the prob. in panic i ran to the net eventually finding you guys. im not sure how far i got down the post but i suddenly realised that if i could twist forward the 3 pronged wheel at top of mechanism i might be back in business. at first i tried a hammer action. no good. next an old pair of angled pliers with a firm and sharp force gave the same result as pushing handle forward and releasing brake. oh happy days again. noel

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Anonymous Poster
#91
In reply to #72

Re: Husqvarna's built-in chain brake problem-repair how-to

10/18/2010 9:17 PM

thank YOU !!!!!!!! YOUR post was the only one that I understood ,,,I had my saw fixed in 2 mins after reading

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Anonymous Poster
#73

Re: Husqvarna's built-in chain brake problem-repair how-to

02/17/2010 1:14 AM

Just had the same problem on my Husqvarna 445. What I did was cut notches into an old socket (used a dremel with cut off discs) and put the clutch cover lightly tightned into a vice and just ratcheted the brake off. Plus now I will always have a tool to use in case it ever happens again.

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#74

Re: Husqvarna's built-in chain brake problem-repair how-to

03/09/2010 2:43 PM

Thank you for addressing this problem, as I am exactly at this point in trying to reassemble my Husky 51. I got as far as your "paste-up" picture in understanding the orientation of the lock spring, but cannot understand the placement in the handle. I figure it goes inside the handle, but in doing this, it no longer fits over the binder actuation link assembly. The exploded view shows the lock spring's pivot point in line with the large lower hole, but on the outside. How can this be? Am I just being dense? I tried to blow up the next pic to understand the assembly, but it was just too fuzzy. Please help!

Thanks

Kate

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Anonymous Poster
#76
In reply to #74

Re: Husqvarna's built-in chain brake problem-repair how-to

03/09/2010 5:15 PM

Hi Kate,

If your talking about the pics in post #61, just jam the spring into the handle as far as it will go. It will compress as you do. Keep pushing until it hits bottom. The orange handle hole the pin goes through is actually in front of the spring coil, not through it as the exploded parts diagram shows. The first picture in post #61 shows the final spring position (except it should be inside the handle). Everything should fit together after that.

Barry

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Anonymous Poster
#81
In reply to #76

Re: Husqvarna's built-in chain brake problem-repair how-to

07/16/2010 10:08 PM

Sir:

The thing that caused me some unease is that the spring in the handle is neither necessary for "normal" saw operation nor essential for kickback-safe chain braking ... provided, in the latter instance, that we are talking about a "kickback safe" brake response that is implemented by the ... forcing of operator's wrist to flex, and the dorsal aspect of his hand to strike the chain brake brake handle as the saw reacts to binding of saw chain on bar tip and rotates uncontrollably upwardly.

(For those not familiar ..., the "back-of-hand" saw chain safe-ing method just described was only the penultimate development along the innoation path towards preventing a "slashing" chain from striking operator's face and upper body during kickback accidents. The reason that initial invention succeeded only partially ..., is that it required operator's forward hand to grasp only in one place (in the plane of the bar), thus restricting more versatile front handle designs—such as wrap-around handles—which would permit more flexible [and easier] saw grasping and manipulation for meeting various cutting orientations and circumstances. The ultimate development, present on recent saw models, including subject saw or this discussion, was the "inertial" chain safe braking system which requires no accidental hand-to-brake-handle contact, but only sudden and "violent" reversal of bar [and brake handle] direction of motion [... from "forward" sawing to rapidly revolving, rearward, about operator's rearward hand and towards his face. Because "accidental" contact with brake handle was no longer required ..., mfrs were free to innovate more versatile saw handling arrangements in their saw designs. In effect, because inertial safety brake actuation is probably earlier (and can be designed to be faster) than accidental hand braking, it would lead one to wonder if the brake handle would ever again actually serve (apart form cocking and to provide moment of inertia) in its original capacity to "intercept" the operator's forward hand during an accident. Now, as to how this relates to your posts ...

I had always surmised that putting that compound spring, preloaded, into the handle could only serve the purpose of triggering inertial braking ... by suddenly releasing the cocking mechanism and then impelling the handle forward to release the pre-compressed (armed) brake drum binder spring. But I just could not figure the chain reaction that makes it all happen. More importantly, ...

Your picture of the handle spring in its mock-up setting—where you've squeezed and tied the spring into "armed" configuration—...doesn't quite explain how the installation in handle and interfacing with the brake arm/release mechanism is to be achieved. In my experiments, I found it near impossible to manipulate the spring while in the handle and yet still assemble handle to brake assembly housing ....

Now, assuming that the spring must be kept restrained as shown in your mock up photo, how are you then able to release (to unbind, to untie) the spring once engaged with the linkage and once the handle is mounted? Can you offer a method of releasing the spring after handle assembly to brake housing...leaving only the spring and nothing else (like the binding material) inside the handle?

Thank your for clearing up of that fine detail.

C. A.

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#82
In reply to #81

Re: Husqvarna's built-in chain brake problem-repair how-to

07/17/2010 12:26 AM

The twist tie in the photos (post #61) is only to show the final position and shape of the spring within the handle. It is not needed for assembly. Just push the spring into the handle as far as it will go. It will automatically compress and assume that shape and position.

You can't push the spring too deep. It hits bottom. You may need a screw driver to push it all the way in. Neither pin (725 52 93-56 or 501 87 49-01) goes through the loops of the spring, as it may appear in the parts diagram. Both pins are in front of the spring, as shown by the photos. Make sure the spring is fully seated, past the first pin hole. Just jam it in as far as possible. Push. The spring will stay in the handle by itself.

The tip of the "binder-actuation link" 501 87 53-01 touches the end of the handle spring (2nd photo). When the brake trips, the tip rotates counterclockwise and compresses the handle spring further. When you pull the handle to release the brake, the handle spring helps push the tip back into the off position. If the handle spring is not in place, you may have trouble resetting the brake.

BTW, you can easily test the brake. With the saw off, hold the saw level and about 14" above a solid surface. Let go of the front handle and let the tip of the blade free fall. Allow the saw to rotate freely about your trigger hand (limp wrist). When the tip of the blade hits, the brake should engage. If not, you have a safety problem.

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#83
In reply to #82

Re: Husqvarna's built-in chain brake problem-repair how-to

07/19/2010 5:16 PM

CowDoc, thanks for all the detail. As I recall, the "inboard/proximal" wire-end of the handle spring seemed to have interfaced with (what was called above) the "bifurcated" spring ... to the point that one side/leg of the bifurcated spring was bent/distorted somewhat. I took this - that the bifurcated spring was "damaged" somewhat - to be an indication of possible miss-assembly. Looking at your drawing, it now seems that "damaged" might have been a misperception on my part(??).

I will study your suggestion further with tool in had and then get back...or try to illustrate any further questions...as to how exactly the spring engages the moving parts near the handle pivot point.

PS: It seems that, just like the binder band pre-load spring, the trick to reassembling the handle spring to handle will be finding a way to do it without hand injury. I'm guessing there's a special tool used at factory for handle spring insertion during initial assembly--after all, no manufacturer wants line workers doing time consuming, difficult, or potentially risk assembly steps. thanks again.

ca

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Anonymous Poster
#77

Re: Husqvarna's built-in chain brake problem-repair how-to

04/18/2010 5:51 PM

Listen to posters 59 and 64. Pull harder to reset the brake.

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Anonymous Poster
#80

Re: Husqvarna's built-in chain brake problem-repair how-to

05/28/2010 8:18 PM

Great thread and wish I'd found it earlier. Having had the same problem, I assumed I must have cooked the clutch. Ordered and received a new one. In looking online for how to do that, I found this thread and read through. Finally dawned on me that the brake was on. Pull harder and problem solved. I can't believe that didn't occur to me. It must have happened while I was using it, as it stopped itself. I had same issue taking off cover, but did get it off and back on again. Don't ask how. Anyway, works fine now, and yes, I do feel stupid.

Thanks all

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Anonymous Poster
#84

Re: Husqvarna's built-in chain brake problem-repair how-to

09/10/2010 1:08 PM

Has the chain brake been activated or the spring removed when the saw is not fully assembled? There is a big issue in putting this back together if you have released the spring tension more than allowed by the saw when it is together since the clutch prevents the spring from going all the way. At this point the chain brake cannot reset the spring, and I found through much trial and error that you have to install the handle, but leave the guard off which is attached with four phillips headed screws, and attach the handle. Secure the housing, as with the vise and compress the spring with a screwdriver, pushing away from the chain brake while gently pushing the chain brake backwards. Pushing the spring backwards a ways will allow the guard to get to a point where it can reset the cam in the locking position. I also gently put a C-Clamp over the center of the spring so it would not sproing. After it is reset, remove the chain brake, replace the guard, and reassemble the chain brake. Just don't activate the chain brake untill you assemble the saw, and it is around the clutch, or you will have to begin all over again. Rick

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#85

Re: Husqvarna's built-in chain brake problem-repair how-to

09/29/2010 10:06 PM

CowAnon,

The Chain brake on my Husqvarna 36/41 is broken. The binder strap wore out. Your forum thread should be helpful, but I am stuck at a point that was not addressed. I suspect you can talk me through this.

My problem is getting the pivot axle apart to remove the large plastic lever. The part #725-52-93-56 is turned by an allen wrench, but it does not unscrew because the other end just spins. There is no apparent way to get a wrench on the other side. How did you deal with this?

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#86
In reply to #85

Re: Husqvarna's built-in chain brake problem-repair how-to

09/30/2010 11:35 AM

Clambaker - I don't have a Husqvarna, so I'm only working from the diagram that was posted [MUCH!] earlier on this thread. I've dealt with similar assemblies, though. My usual method is to use a Dremel (r) rotary tool with a mandrel and cutoff wheel to make a slot in the face of the part. Use the thin ones, #409, rather than the thicker #420. Use one that has worn down to 3/8" (10mm) diameter so that you can go closer to the edges without damaging surrounding material (I keep worn ones specifically for this purpose!). Now you should be able to hold it against rotation with a screwdriver or similar tool in the slot. And, good luck!

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#87
In reply to #85

Re: Husqvarna's built-in chain brake problem-repair how-to

09/30/2010 1:17 PM

Let the arm soak in WD-40 or turpentine for a while. A hand held impact driver may help too. The kind you hit with a hammer to make it turn. They're a few dollars at Harbor Frieght, a little more at Sears and a lot more at auto parts stores. A useful tool to have around. A small air power impact driver would be even better.

I used vise grips to clamp one face to the other. I may have use a small piece of wood between the face of the metal washers/grommets and the pliers. That raised the pliers above the plastic. Clean the WD-40 off first to reduce slipping. That alone or in combination with the impact driver, should break it loose.

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Anonymous Poster
#89

Re: Husqvarna's built-in chain brake problem-repair how-to

10/08/2010 11:58 AM

Hi

You took the side cover off with the brake set.

Remove bar and chain set side cover on bar studs to get some leverage then move brake handle back till it clicks. There you fixed the problem

Simonian's Saw Service

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#90
In reply to #89

Re: Husqvarna's built-in chain brake problem-repair how-to

10/08/2010 12:14 PM

How does this differ from #67?

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#101
In reply to #89

Re: Husqvarna's built-in chain brake problem-repair how-to

02/13/2012 1:44 PM

A simple way to reset the chain brake for newer models like the 455. If it is the design that has the brake handle mounted on the saw body and not the clutch cover, and you tripped the brake taking the cover off, here's what I do...

Remove the chain and bar. Bring the engine up to the start of the compression stroke. Then with a hammer and medium size screwdriver, jar the the clutch drive loose with a sharp hit (clockwise). Unscrew the clutch and slip off the drum. Now, install the cover while aligning the 3 point wheels. Grab handle and pull to reset the brake. Remove cover and install the clutch, bar, chain, cover. Now your ready to go!

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#102
In reply to #89

Re: Husqvarna's built-in chain brake problem-repair how-to

04/27/2012 6:35 PM

"#89 Remove bar and chain set side cover on bar studs to get some leverage then move brake handle back till it clicks." Also used screws to hold in place.

Great help and very simple. My situation was that during reassembly after chain change I misaligned the brake with the cover plate and the saw gave a pop sound leading to the same problem as described although I did not understand what happened at the time until this thread. Thanks so much.

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Anonymous Poster
#92

Re: Husqvarna's built-in chain brake problem-repair how-to

01/01/2011 9:36 AM

I loved your line of questions. I found your site because I had the same problem and no one knew how to fix it. I have an old 288XP and as I was cleaning it with the cover off I accidently bumped the chain brake and it locked. I could not get it to unlock no matter what I did. I thought about taking it apart and then realized that probably wouldn't be wise. The Lord gave me the idea to put the cover back on just enough to hold it so I could pull it back and guess what?? It works. Anytime this happens it only takes seconds to correct. Thanks God He's God is all I know to say.

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