Grooves in a Crankshaft Caused by Oil Seals

If the 'groove' is a smooth shiny polished ring the option 1 is favourite.

In fact as long as it is circumfrentially* smooth I'd say 1.

I'm willing to get shot down...but that's my feeling, uless you are going to have the whole thing (all the journals) ground....which is probably the way to go now you have the damn thing out...
Drat ..I appear to have changed my mind...but hey ...that's a cats purrrr-ogative

Del

* Dunno if that's a legit' word but I'm sure you can work out what I mean...e.g it has no axial roughness which would tear the seal or pitting which woul allow leakage.

Probably option 1 as Del said.

How much will a 1991 Honda with 240K miles be worth, even with a new engine?

I assume you are not looking to make this a historical showpiece and more of a work horse. So if it leaks a little oil, so be it.

Check with the dealer if you want a better opinion. You could always install a new crank, but I question the value of doing that if the finished car is only worth $1500-$2000.

I see this a lot on many high time engines. Even on air-cooled aircraft engines.

The wear was modest and well within the range over which a new oil seal can conform.

I agree with the others: polish it as best you can being careful not to change the geometry and simply install a new seal.

L.J.

Thank you

Your comments are very helpful

I gave you a GA point but I must add this.

You said:"most of the time grooves like this are caused by dust and dirt in contact with the seal."

It has been my experience that old seals become hard and wear on the shaft as well. I have used the repair sleeves on cars and farm equipment in the past and would not hesitate to do so again. I have used them with and without a flange as the situation dictated. I have also used off-set seals. All great products.

Hello Denis you said:

2) Machine the crankshaft until the grooves are gone? By reducing the diameter of the shaft wouldn't that result in oil leak?

Or I should say asked the question. I don't think that would cause a problem. I've never had to have a seal surface recondition, but I am sure it is possible, if severely damaged and the crankshaft core is valuable enough the surface can be built up by welding and turned back to standard diameter . However there is a much simpler solution.

Assuming that you are disassembling the engine, I would check with a local automotive parts house, to see if a crank kit is available for that engine, Or if not available as a kit , get a turned crankshaft, and the appropriate oversize bearings. Generally the crankshafts are available for exchange, for a reasonable price.

Alternatively if there is a crankshaft shop in your vicinity they would be the expert on reconditioning your crankshaft, possibly by polishing the surfaces the seal rides on. However just exchanging the crankshaft is generally cost-effective.

Failing that, the sleeve, or attempting to relocate the seals so they do not ride on the damaged area of the crankshaft should both work satisfactorily.

Now for the disclaimer. I know absolutely nothing about parts availability for Japanese automobiles. If it doesn't have eight cylinders and a heavy iron block it doesn't belong in an automobile, just kidding I can see no reason for a popular vehicle not to have readily available replacement parts from a normal automotive parts house. As far as buying anything from the dealer, you could probably get a short block cheaper from a supplier, than a new crankshaft from the dealer.

The sleeves that we are speaking about are designed specifically for the application described. It is only about .010 thick. It is finished exactly the way the seal manufacturers want it finished, because they are the people that sell the sleeves. The sleeve is only about twice the price of the seal. These sleeves are just tapped onto the shaft with a small amount of sealer under it. There is just no other practical way to deal with the groove.

Hello Bob:

I've seen the sleeves used to renew the front seal surface of the crankshaft. As I said before I am not familiar with his engine. It would be impossible to put a sleeve on the rear Main seal surface of a Chrysler B engine as well as most pre-1990 domestic American automobile engines. (Okay I know I'm a relic) after that point I know at least General Motors began using one-piece rear main seal's. I'm in complete agreement with you if he's trying and stop an oil leak in frame. However I am operating under the impression that he is rebuilding the engine out of frame. It would make sense to put in a reconditioned crankshaft (provided they are available and reasonably priced) thus assuring not only a good seal surface, and proper tolerance on the Main bearing in Rod journals. Fiendishly this also puts a problem of what to do with the seal area in the rebuilders hands.

What has good sense got to do with this thread? If he had any sense, he would not be playing with Jap Crap. Oh no. Now look what you made me do.

I couldn't agree more!

I wish to add though that the rubber neoprene seals will cut nodular cast iron cranks eventually so machining wont fix the problem permanently.

speedy sleeves are made of wear resistant steel so the seal won't groove it, it is a permanent solution.

the groove is actually caused by the rubber cutting the soft metal. You can buy special crank seals which have a wide grooved surface which doesn't cut into the shaft however they do sometimes leak if left stationary for long periods as the mating surface has tiny grooves to channel the oil back to the sump. When stationary the oil can seep through

Check with your bearing/seal supplier...

The bearings and seals should be available in +/- sizes to accommodate this problem...

Then all you have to do is get the crank polished to the appropriate dimension and install the proper bearings/seals...

Any good automotive machine shop should be able to handle this for you...

BTW...

If you removed the crank (Obvious) I would not re-install it without new bearings...

Unless you like doing this again, new bearings are cheap insurance...

Have fun...

Dennis,

Simply install the new seals at a different 'depth' to the old ones. Half a mm (.020") is all you need. Deeper(further along the shaft), or not as deep, as you see fit. If the seal is located by a finite depth housing make a simple spacer and use sealant around the outer circumference. 'Redisleeves' or 'speedisleeves' as they are called here are a good fix, but not always warranted. If you do opt for the relocation type of fix, 'strop' the shaft with some 1200 grit wet/dry paper, lubed with WD40, kerosine, diesel, or light oil, and wash it well.

It won't leak.

Cheers,

Stu.

I would either get a new or remanufactured crank, or have the existing crank reground and/or hard chromed to bring it either back in spec, or turned down to fit with standard oversize journal bearings. In general, you are better off hard chroming to bring it back to spec than turning it undersize and using oversized bearings. The thicker the journal bearing is, the lower the max bearing load it can handle before extruding. The fact that the oil sealing surface is damaged is a good indicator that the other journals are possibly worn as well. I have no experience with Redisleeves, but I have to say that given the fact that you already have the engine disassembled and it would be really simple and straightforward to replace or reman the crank, I would do that before I took a chance that the glue/sealant won't hold or that the sleeve would damage something. For want of a nail, the kingdom was lost. Shortcuts taken at this level will plague you for a long time to come.

Rorschach,

the fix suggested by myself and Bobc and others along those lines are not cheap, temporary fixes. They are engineeringly sound, as practised by the likes of myself and others over the past 60 years of professionally fixing busted motorcars, (and other things). When you don't have to buy a new crank, or reman, then why? Why add to the capital cost of an old car unneccesarily? This fix doesn't in any way compromise the strength or integrity of the shaft.

Cheers,

Stu.

Stu, don't get me wrong, I said I had no experience with them so I really can't speak to how well they work or not. I could see where not cleaning the oil residue off the shaft well before applying the sealant could lead to adherence problems if I'm visualizing the product correctly, but YMMV. I CAN see where if something WERE to happen, then addressing the problem later after the engine is assembled and back in the vehicle could be a major pain in the tookus. I prefer simple solutions whenever possible, clearly if he sees the value of rebuilding the engine at 250k miles, then there is possibly a decent business case to spend the extra money to make sure you go back in with a crank that is known to be straight and crack free. But again, that is his call.

Hello Rorschach: In general, you are better off hard chroming to bring it back to spec than turning it undersize and using oversized bearings. The thicker the journal bearing is, the lower the max bearing load it can handle before extruding.

I had never considered the bearing thickness and extrusion. I'll have to think about that but it sounds plausible, certainly with softer bearing materials such as Babbitt, though I don't believe it would be a big issue with a tri-metal bearing.

I have run high performance engines with 10 10 cranks, and tri-metal bearings and had no problems. Of course the bearing loading on a modern engine may well equal or exceed that of the 600 hp 426 hemi. Probably more from tradition than need I won't run a crankshaft turndown more than 10 thousandths in a high performance engine. I'm with you I will hard chrome the crankshaft after that point and bring them back to standard.

Regular street engines I have no problem with any undersize of the Rod and Main journals, of course I prefer standard or 10 10, I've never experienced any bearing extrusion there either, and of course I use cheaper bearings, so I don't think he'll have a problem with that.

You've given me something new to think about, so thank you, even if we semi-disagree that it's an issue. Something that could be an issue (and I'm with you on suspect of the crankshaft's wear) is surface hardness some cranks are, or used to be nitrated, of course this is only a surface treatment and you lose the hardness of the surface when you turn a crankshaft. If I am building a premium engine for the long run I have the cranks nitrated, or chromed back to standard, love chrome nice hard surface. Considering the vehicle I wouldn't think it would warrant the extra expense.

I'm a Star Trek fan, and one of my favorite quotes was from the next generation. "A good engineer is always a wee bit conservative, at least on paper" Scotty in the episode relic's.

We used to think cast crankshafts were junk only useful in grocery getters. The cast crankshaft out of a small block Chevy 400 was a favorite to make a stroker by turning the mains down and installing it in a 350 block, and held up well in dragracing even after doing another no-no , the Rod and Main journals no longer overlapped. I doubt even the Japanese have their pencil so sharp the bearing shell that is five thousandths thicker will have any problems.

Back when I worked at a company that reman'ed babbitted hydrodynamic steel mill roll bearings we had to de-rate the thicker babbitted bearings unless we went to a harder babbitt (like Cadmium babbitt). The bearings were a steel shell that had babbitt centrifically cast into them, if we had to open the steel shell up to much, we had to de-rate them. we also manufactured new replacements and we found we could actually rate them higher than the originals if we kept the babbit as thin as possible.

Check with your local auto parts store there is a product on the market that combines a seal and a thin sleeve that is pressed over the sealing area of the journal of the crank shaft.

Once installed you will have a tight seal.

You can spray heated metal onto the crank shaft and re-machine the shaft back to the original spec but, as has been pointed out, this is getting rather expensive for a car with a quarter million miles on the odo.

Maybe you can just stuff the gap with cat fur?

DennisWaller. You have not made any mention of any additional wear, or damage to the crank. If everything else is within acceptable tolerances, sleeve the seal area. If there other concerns about this crank, get an exchange crank kit. It should come with bearings that match the newly cut crankshaft.

All the bearing journals, both main and connecting rod, are within shop manual specs. The only damage to the crank are the grooves in the seal seating area. I have decided to use a redi-sleeve on the rear seal and re-position the front seal so it rides on an undamaged section of the crank.

Dennis Waller

Please report to CR4 on the condition of the crankshaft (apart from the oil seals) since we are getting opinions on replacement/exchange alternatives without the benefit of this important information.

No meaningful recommendation can be made without this information. Posters are assuming facts not yet in evidence.

I imagine that the seals are double lipped, with the oil sealing lip facing inward and the dust seal (minor lip) facing outward. If the wear is mainly under the dust seal lip, I would not worry about it at all -- just install new seals. If the wear is without rough spots, and I suspect it is, and on the actual oil sealing area, then again, I would not worry at all, just install new seals. Even if the grove has a relatively distinct edge which you can feel with a fingernail, (but which does not actually shave stuff off your fingernail) again, I'd not worry, just install a new seal. The new seal, being unworn, will have higher lip force than the old one, and will wear (break in) to fit the groove. Once it fits the groove, it will stop wearing and will seal well, with increased lip tension over the old seal, which will have had its lip worn away over the years. It is hard to imagine any case in which the grove is anything other than perfectly circumferential (it has been turned by a lathe, effectively). .002 - .005 is not near deep enough to reduce seal tension to the point that the seal will not work. Obviously many cranks are reground, and the resulting seal land can be much smaller than original, but the original seal size works fine.

On the part of the seal that does the oil sealing, the lip usually wears to a wide surface, causing a wide wear area, The new seal will have a much narrower sealing surface, and will be under much greater tension (you can verify this for yourself by sliding a new seal onto the crank (out of the engine) and compare the force required vs the old seal.

If it makes you feel better, then install the sleeves made for this purpose, but if you can't find them, I wouldn't worry. I am assuming you have thoroughly miked all the journals on the crank, and they are within wear limits in every respect.

If your crank is in good condition is other respects, you can expect another 240,000 miles from the engine before regrinding is necessary.

Hello Ken you said:"Obviously many cranks are reground, and the resulting seal land can be much smaller than original, but the original seal size works fine."

Of course being a relic I'm most familiar with Detroit iron, particularly the Chrysler B engine. The seal surfaces on these engines, both timing case and the rear main would not commonly be turned down as they are separate from the Main bearing journals . In fact I'm having a little trouble envisioning an engine that the area the seal rides on and Main bearing journals would be continuous. BTW I had to think about this a minute last night as I was thinking sealing surfaces were turned down when the a crank was reground. After consideration I realized they were not, course it never hurts to have a crankshaft in the garage to go look at.

PS: I agree with you, polishing the crank a few thousandths would cause no problem with the seal.

Hi Dennis,

The shaft is worn very smooth if you measure in RA about 5-10 which a 1 pc design shaft seal which has .040-.080" interference will seal just fine. I would not polish the seal surface as it is just fine. Check seal interference if you have .080" you can grind the shaft and still have plenty of lip seal loading. Sleeve's will work fine also. Different subject install new pistons as the ring lands are worn and just installing new rings in old worn piston ring lands is a bad deal. It will let combustion gas's enter the crankcase and you will have less power and mileage. Your engine had some blow-by at the rings which could have made the seals start leaking anyway.

Hope this helps,

Mike

Grooves in a Crankshaft are caused by Oil Seals. Grooves in shafts are caused by not replacing the oil seal as recommended by manufacture. Most metals (except gold and platiumn) will form a surface oxide example (rust) when it comes in contact to air,water,carbon,or chemicals. This oxide is embedded in the seal material creating a polishing or cutting action on the rotating shaft making a groove. Check the seal manufacturer specs for this information. A car with 100,000 miles, avg 50 miles per hour,has operated 2000 hours, when I looked up a seal specs several years ago, the recommended change out was about 900hrs or about 45,000 miles. Seal material and technology improvements along with improved lube oils over the last few years should help reduced wear from oxide contaminations. Changing the oil seals and installing correct seals per manufacturer recommedations will help reduce some of the oil presently dripping on our roads and parking lots that is polluting our water systens. New Seals won't improve the engine preformance, It will reduce oil loss, and helps save our natural resources. Conserving thru Efficiency DonnieH

Thank you to everyone who provided comments and suggestions.

Since reading these comments I have discovered that BCA/National makes a "redi-sleeve" for the rear main seal of this engine and I will try that approach. In the front I have decided to use a stock oil seal but not drive it to the bottom of the pocket which will allow the seal to run on an undamaged section of the crankshaft. Slight oil leakage in the front of the engine is not a serious problem but leakage from the real seal would contaminate and ruin the new clutch I will install.

To clarify some facts: the engine was removed from the car and completely disassembled; I measured all the main and connecting road bearings and all journals were within factory specs despite the 230K miles. (The oil had been changed every 3K miles.) This is a 1.5 L 4 cylinder engine which produces only 90HP so the five main bearings operate under very low stress levels. The insert bearings I removed looked pristine. Since the grooves on the oil seal surfaces are the only problems with the crank, I think a sleeve is the best and most cost effective approach to the problem. By the way several automotive technicians have confirmed that simply replacing the seals and allowing them to run on the grooved area of the crank would cause the seals to leak after only a short period of time.

Dennis Waller

Good lad.

You'll find that this engine will do another 230k miles with a modicum of care and good quality lube oil, regularly changed.

My fleet vehicles regularly make it to half a million kilometres, and they're 800cc and 1300cc motors, driven 'pedal to the metal' so as to keep up with traffic. We never exceed 8k kilometres for oil and filter changes.

Cheers,

Stu.

A plethora of technically correct responses, but monetarily speaking, $10-15 spent on a seal and sleeve kit from your local parts store will reseal the front. The rear will typically require separating the transmission from the engine and also a seal and sleeve kit(if available). And in most high mileage applications, the front seal of the transmission will also be drooling. Good luck.

Considering the time and energy (yours) involved, #3 + "for sale"

You could take the shaft to a machine shop, have it welded and turned. This is what I did with farm tractor (leather seals).

your third choice is the best. Go get a speedy sleeve "cheap way" or if you are rebuilding it, go get a new/ used crank. Honda's are so cheap for parts. You can get a JDM engine engine with 30K on it for under $400, so I would think someone would have a crank. Post a "wanted good condition crank for honda" on cragislist.

I ran into this same problem with my honda civic d16z6 motor with 138.000 miles.I checked with BCA national and timken about their redi-sleeve but i thought the cost was to high $34.99 rear and $19.00 front plus $22.0 shipping so i checked on the internet and found a place called micro-sleeve phone#1-800-475-3383 and they told me they make sleeves for all engines and companys including fel pro and fel pro sold a sleeve for the rear main for honda 1.5 1.6 1.8 2.0 part#16275 sold at oreillys for $12.99.Fel pro did not sell the one for the front but oreillys can order it part#ms-345-1 this is a micro sleeve part # also have napa part#front600250 rear is#6002564.I installed these on my engine and they were very simple to use with great results.thanks for all the good advice on this matter hope this helps.

did the $12.99 include the seal as well? Some times the specialty suppliers will package a group of related parts together. That assures that they sell you a complete compatible package. It also insures that you do not buy the other parts from another vendor. Good for you for being smart enough to shop for what you needed.