Testing a Master Cylinder

GO BUY A NEW MASTER CYLINDER, NOW.

Or take it to a shop and have it fixed.

If you are not a competent mechanic and try to repair it yourself and fail, YOU COULD KILL YOURSELF. OR SOMEONE ELSE!

The caps are on purpose!

Bought a new one and put it on according to directions (bench bled it, etc) Still the pedal goes all the way to the floor. I am going to read up on how to bleed the brakes for this vehicle. I also found another site where it was mentioned that I need to adjust the plunger. I'm not sure how that would have gotten out of adjustment but if the bleeding doesn't work I will try that. If that fails into the shop it goes because it will be beyond my ability and tools probably.

Thanks for the instructions. What exactly is a proportioning valve. I know a little about cars and have never heard of this. Thanks again.

It's a valve in the line that limits the flow of brake fluid to the rear wheels so that they don't lock up when braking. Less weight on the rear wheels when braking, due to weight transfer.

"proportioning valve" may be the problem. By pumping fluid back through the valve it may have been moved into the "back only" position. It's a differential pressure valve.

bob c would know if I on to something.

On an older car like this the brake line mains that run from the master cylinder to each of the rear wheels can corrode through. The brake fluid leak will then appear under the middle of the car.

New lines prior to bleeding the system should fix this problem if it is indeed the source of your system failure.

Well put! GA.

I really agree with you. Gentleman must be in confusion now. Please do not attempt any repair by yourself. Let mechanic do his job. He will be more competant than you. Brakes & steering should never be fiddled.

Don't!!!

You indicate you know nothing at all.

Don't, especially, start learning with the brakes. It could be other things besides the master cylinder.

Aside from killing yourself you could kill others.

No offense meant but please take it to a shop that knows brakes.

j.

Wow what a reply, a bit over the top but what the heck. Not sure I said that I know "nothing at all" just not experienced there is a difference. Well I guess thanks for your concern, I will try and not KILL myself and too many people by bleeding the lines.

Perhaps I was not specific.

I meant nothing at all about automotives.

That little bit about testing a master cylinder by sticking your fingers in holes says it all.

It is not possible to be over the top when somebody might kill themselves and others.

j.

did you pump the lines to get the air out of the lines!

I worked at Sears for a while. We did all kinds of checks when we did an oil change but one thing we never touched was the brake fluid cap. We never checked the brake fluid for a very good reason. It is way too easy to mess up the brakes and Sears did not want to be liable for any brake related catastrophies down the road. If a big company like Sears won't touch it then I would suggest that you do the same. I am not trying to suggest that you are incompetent or irresponsible, just that it might be in your best interest to heed a word from the wise. Pay the professional on this one. I have done it all, even down to replacing the plastic caliper pistons on the Dodge station wagon of yesteryear. Let's just do it right dude.

Get a new master cylinder and bleed the air and/or debris out of the lines and calipers. Finger test is not conclusive. AL

Here in Satellite Beach Florida we use a tow service and for $25 bucks it takes the car to the shop. Great concept. Brake job is left to mechanic that is not guessing....

Good point!

Without working brakes it doesn't want to be towed. It wants to be piggy-backed on top of another vehicle.

Lighten up?

Perhaps time to jump on you!

There are other possible causes for his symptoms let alone that he appears to be someone who might not be able to accurately report the symptoms.

As far as getting it to the shop no doubt he knows how to call a tow truck.

j.

Keep in mind that if you have ABS you'll have to go through extra steps bleeding the brakes, more so than the conventional brake systems. Different manufacturers have different procedures. Get yourself a good repair manual that covers your system, conventional or ABS and read up on it.

Good Luck

Having given you advice now, I must tell you that two of my vehicles have ABS, and I will not even change brake pads on them. I take them to someone does it for a living.

dj95401 is correct.

Good luck and keep it safe.

Thanks to everyone that gave constructive advice especially LynLynch, very good direction.

Unfortunately I bleed all the brakes and the pedal still goes to the floor. I've tried everything that I think I can do so will bring to the shop Monday. I will post an update when I find out what is wrong (I always like it when people post update with the answers) Thanks again.

"I will post an update when I find out what is wrong"

_{To be followed by a collective slap to the forehead!}

Have you verified that the pedal is pushing on the master cylinder?

abs or no abs changing the pads is a plug and play idea from all the hoopla so far it sound as if the slave cylinder went bad on a 95 honda abs was an option not standard the slave cylinder sends fluid back to the master with the parking brake set cycle the parking brake while bleeding the brakes to see if there is fluid loss

Does your Honda have power brakes? If so, with the key off, pump up the brakes. Hold the peddle and start the engine. If the peddle goes down the the power assist is working if not then your power booster requires replacing.

Backyard since age 10. Tossing this you're way hope it helps, then get a repair manual.You'll be glad you did.

Or has an air leak

Check the wheel cylinders. Might be time for attention. Remove and replace is the easier then rebuilding. A repair manual will help.

Brakes are normally not too complicated at the level you are looking at. They are basically a foot pushing on a pedal that pushes a piston that displaces oil that displaces a piston that presses the pads on the disc/drum - that said there is then air/vacuum assistance and a splitting of the system for safety and more lately ABS on top of that. I don't see ABS as the issue and the absence of vacuum assistance would just make the pedal hard, leaking caliper seals OR A RUPTURED brake line would show fluid on the floor/vehicle, you say not this. Air in the system at a modest level would give soft/limited braking and it seems that might be your case. You say you've now replaced the master cylinder and the problem persists.

The problem has to be that the air bleed was not done correctly - some systems are hard to bleed and you might need a power bleeder.

I use a home grown bleed system - about 15 psi from my air compressor to the top of the fluid in the reservoir, then loosening the caliper bleed screws and watching the air/fluid bubbling out through a transparent tube into some brake fluid.

I'm still taking it in but let me throw another variable into the equation. I don't know if I was suppose to but I had the car running when I was bleeding the brakes. (We actually bled another time with the car turned off, I mean I really bled this thing) My helper was in the car pumping the brakes and then holding the brake to the floor at which time i would loosen the bleeder screw, let the fluid out. I would then tighten the screw and she would let up on the brakes and start pumping again. I did this until until clear new fluid was coming out. (The old stuff was really nasty) Only on one of the lines did I seem to have air. The new variable is that when she was pumping the brakes the car would really idle down which leads me to believe I have a vacuum problem. Could this be part of the problem?

I appreciate the advice even though I'm taking it in, I like to learn new things all the time.

Can't add a lot.

Subtle point is that I would normally loosen the screw and then press the brake. Shouldn't make much difference.

That you got old fluid out and some bubbles says that the fluid is pumping through - as it should when you have a new master cylinder.

The engine slowing down is possible as when you press the brake pedal, air is let into the brake boost vacuum chamber and that adds force to the oil piston in the m/cylinder. It's a while since I got to this level of detail but I am thinking that the engine would continue trying to evacuate the now non-vacuum side of the booster while the pedal was down, via the inlet manifold, and that this could/would change the air fuel ratio and possibly change engine speed. Don't see that this relates to your basic problem though. I am still thinking, a serious leak you haven't found and air not bled out.

One hidden problem (mainly in very old vehicles) can be that the inner wall of a brake hose separates and this stops fluid flowing to a wheel or two. I can't see that this is your problem either, unless a reverse of this is causing air to be sucked in when the pedal is released.

"Subtle point is that I would normally loosen the screw and then press the brake."

but the OP was

"pumping the brakes and then holding the brake to the floor at which time i would loosen the bleeder screw,"

Pumping the brakes with the bleeder screw open would be a no no. I know this is not what you were suggesting.

Simple solution to this problem: bleed brakes with motor OFF!

Then idle speed will not be affected.

Yep bled them both way with engine on and off, just thought the idle might be a clue that I couldn't figure out, apparently not.

And yes you are correct We did not pump the brakes with the bleeder screw open.

I have to go with the other poster and say that I have a leak tha I can't find. I know it's possible that their may be air left in the lines but I would be surprised after all the bleeding.

Stick a fork in me.

When all else fails, take it to the man.

Good luck.

BTW, I came here with a car related question just about a year ago. I never left. I'll bet you don't either.

Welcome aboard.

Lyn

LOWIQJO,

I just gave you a GA.

Some of the folks giving this poor fellow suggestions did not, obviously, know very much about cars, let alone brake systems themselves.

If he wants to work on his car, and he should as should every driver, or at least know how to, your suggestion that he go to school is good.

There are also books in the local library that address not only particular cars but also specific systems in those cars, electrical, brakes, etc.

Before that it is also helpful to get some experience with tools and things mechanical then you understand the futility of testing an hydraulic cylinder with their fingers or of pumping the brake pedal with the bleed valve open.

Folks that seek assistance here need to have enough comprehension to judge the value of the answers they might get as do the folks here offering answers needing to judge the capability of those that are asking.

As well, this being the internet folks need to realize some of the folks responding here don't know S from S.

On the other hand folks who demonstrably have little experience on things mechanical ought not to be trying to fix such things as brake systems insofar as they control something on the order of a ton of mass.

Those cars you drive must really be old. Cars whose master cylinders leak fluid onto the floor in front of the driver do not have vacuum assist cylinders so that the brake pedal is actually pressing on the master cylinder push rod projecting into the driving compartment.

I have not seen a car without an assist cylinder in many years.

j.

I have to tell you Jack you are one arrogant, self righteous SOB. LynLynch gave some good advice with a couple of other people trying also. But you, nothing but self righteous, holier than thou crap. (knows nothing, unable to accurately report symptoms, futility of pumping the brakes with the bleed valve open ( not even accurate).

If I ever post here again (which i doubt I will ever do) please don't answer. You have no credibility. You never have anything of value to say just flapping your jaws to try and make yourself feel important. Well I'll stop now no sense talking to you anyway, I have a feeling you never listen anyway, cause you already know everything. Buzz off.

You are the one who is completely off base, Jack gave some good advice (as did some others), you should realize that we could be seeing you again soon, on the Darwin Awards page......

Darwin Awards

To my mind, nothing Jack wrote was offensive, it was in some areas funny, so if you can't take a joke maybe you are on the wrong Blog anyway.....

Remember, some things that you may NOT understand can kill you, incorrectly repaired/adjusted brakes are a good way to kiss your rear end goodbye (and take some innocent souls with you!).

You owe Jack an apology, BIG TIME!!! As he could report you and maybe Admin will see it his way (I do!) and make you an ex-member very quickly........

Have a good day in spite of Jack and myself.......

Report away pal, I said nothing more offensive than Jack. (and certainly no more offensive than your silly Darwin award) I came to this site to learn not listen to diatribes from people. If you have something constructive to say that could help me solve my problem then please post again. If you don't then keep your silly opinions to yourself.

You are totally off base, calm down, re-read all posts (without any bias to your own) and you might just see where you went wrong.

If you cannot see that you were the one to go "un-cool" then you should be the one to leave......not Jack.

I thought Jack kept himself in check quite well......but nobody else involved did!!!

I see no reason to change my mind on anything, what about you? (stay cool!!)

"then you should be the one to leave......not Jack."

Where did I say Jack should leave? I just told him to leave me alone, I'm not interested in his pompous mutterings any longer.

"I see no reason to change my mind on anything, what about you?"

I never asked you to change your mind on anything, I simply asked you to contribute something of value to the problem I am trying to solve or keep out of this. (sorry I can't think of a nicer way of saying it) If you recall you were the one who "threatened" to report me for, well I'm not sure what. (That's the definition of "uncool") Just trying to get help with my problem and appreciate the people who have given that help.

Obviously I can't stop you from replying but I will not answer back. I'm sure the good people of this site are tired of this sniping. So feel free you will get the last word.

Thanks for the last word as I am off on holiday for a few weeks and unlikely to be online again until I return....

Stay cool.....

Wait just second there. Your vacation request was not notarized in triplicate. Please resubmit again. I will try to have an answer for you by the end of the year. Sorry for any inconvenience this might cause.

Enjoy the holiday!

It was great!!!

Hi Jack... (No Pun intended.. )

Thanks for the GA.

My first time on the site.. it looks like a good forum for the public to get answers to all sorts of questions etc;

Your correct in the leaking fluid on the floor aspect, I was seeing what type of system the unit has with out trying to confuse the poor guy anymore than he seems to be now...

I do agree 100% with your comments on how people should interpret the advice given on the site & who is given it etc; you must have your Bull-S*&t radar on at all times...

Cheers & thanks again for the thumbs up..

LOWIQJO.

"My first time on the site.. it looks like a good forum for the public to get answers to all sorts of questions etc"

Apparently not for the public only you super smart guys that know everything!

"with out trying to confuse the poor guy anymore than he seems to be now."

I am confused as to my brakes however I didn't hear any great ideas out of you or jack, just self righteous crap.

"I do agree 100% with your comments on how people should interpret the advice given on the site & who is given it etc; you must have your Bull-S*&t radar on at all times..."

You and jack can write back and forth and tell each other how smart you are.

"Your correct" Don't want to confuse you, you poor guy but it's "you're" not Your. By use of your logic you should not type anymore and should go to a professional to type everything for you.

Wow what did I get myself into by signing up for this site.

Hi TM3912, sorry if I offended you with my comments of the "poor guy". It was not my intension. Yep, Grammer & spulling is not bestest points.. .

I was agreeing with Jack that sometimes people will comment or make a suggestion that might lead you into more trouble or prolong the diagnostics for you.

The site is a good forum for feeback & alike. Please continue to use the site, I will, I definately do not assume to know it all, so please don't think that.

I will say that the suggestion that you have receive thus far have been very good. Like you say, some for you fixing it & some for a professional... Ultimately, the decision is still yours...

Cheers for now & once again my apologies if I had offended you.

LOWIQJO..

OK Low I probably over reacted, my apologies. (That was a low blow about the spelling I make mistakes all the time) I don't like it when I can't figure something out (Not to sound arrogant but I usually can figure stuff out) and reading jack's huff and puff about nothing sent me over the edge.

I am going to try bleeding the brake lines one more time. Either I did a poor job of explaining how I did it the first time or by the comments I did it wrong. So I am going to reread Lyn's instructions again and try it one more time step by step.

G'day today TM3912, no problems this end mate.. Don't worry about flying off the handle.. I do it frequently.. (wife & two teenage boys will do that to you ).. give Lyn's inst' a go as you mentioned.. I remember with some vehicles I have repaired over the time, some of them were real mongrels to bleed & it was for no real reason... just the method used at the time...

Good luck & keep using the forum.. even if to say G'day every now & again..

cheers mate..

LOWIQJO

...then please exert your citizen's rights and leave it as soon as you like. You will never know what you are missing either way......

One can get pills for that these days....

Had a look at all the replies re this thread and cannot say I agree with your "did not obvioiusly know every much" sentiment. Most of the advice was pretty reasonable, though some seem to have misconstrued what I said. In case that was part of the basis of your claim let's just say that I know more than most (people not experts) on the subject and that perhaps my expression was lacking.

There is some risk in fixing your brakes, but I think some respondents are overstating it. Most things that a home handyman would reasonably do will, at worst, do no worse than the sorts of things that mechanical failure over time will produce anyway. In this case it is unlikely that a serious repair effort by an amateur will "fix the brakes" in a way that will make then very dangerous in the future.

If you think this view is wrong then perhaps an example would be appropriate before condemning it. It might be that I am being optomistic. I recall with a smile the words many years ago of my chief design engineer who reported that there is, "idiot proof", and then there is, "soldier proof".

And to put things in context - most of those who might disagree with me and agree with the proposition that amateurs "shouldn't touch the brakes" will still be willing to change their tyres even though there are at least two mechanisms that will potentially and very quickly cause a fatal accident - painting the mating hub surface before replacing the wheel (as part of painting the hub to make it look good), and not tightening the wheel nuts properly i.e. tightening them to near normal and then driving very aggressively.

Reflecting on your points about "all use boosters" and "cars who leak onto the floor do not have booster cylinders".

You are correct about the former, A Ferrari F40 is about the only one I can think of off the top of my head.

As to your second point, your experience must be different from mine. At least two of the cars (one very new) in my garage have power assist and could leak fluid from the master cylinder inside and onto the cabin floor. The power assist is on the far side (from the driver/pedal) of the master cylinder.

Hi Trevor I whole hardly agree with your comments. Well stated.

Sometimes I will go overboard on things & I usually do it with-out thinking of the consequences... (my wife will be the best person to speak to about this subject)..

I also had to say that we are not all perfect in our spelling or grammer as well... especially on these types of sites, & especially when we type quickly or thinking twenty words ahead of what has been typed... eg: "that will make then 'them' very dangerous in the future".

Your views on tyre changing as well are so true.. first you must jack up the vehicle safety. This in itself if full of danger & can lead to personal injury. As I mentioned before, Safety is paramount in any given situation......

I appreciate your follow up comments, I & have enjoyed your views. Good luck with the repair & please, let me know what was causing the pedal to go to the floor. Follow up responses will assist the other contributors in future postings...

cheers for now again..

Joe..

Hi Trevor.. I see where I also mislead you with the "leaking onto the floor" I just re-read my initial posting.. I agree it sounded a little vague. the 'external' leakage I was speaking about was onto a garage floor on the drivers side... sorry for any misleading info..

The M/Cyl will leak between the boost chamber & the m/cyl itself. The fluid will run down the boost chamber onto the floor. Another sign of any brake fluid leak that other people forget is Paint Peeling, as brake fluid is very dangeroud on paint work & will lift it quickly if not washed off as soon as possible....

Also Trevor, when bleeding a brake system with the aid of a second person, have them go at a steady pace. If you pump the pedal too quickly, this will create cavitatiion with-in the system & will make the air harder to bleed out as it will be broken up into smaller bubbles & be dispersed thru out the system even more...

As mentioned prior .. good lucke mate.... cheers ..

joe

"Also Trevor, when bleeding a brake system with the aid of a second person, have them go at a steady pace. If you pump the pedal too quickly, this will create cavitatiion with-in the system & will make the air harder to bleed out as it will be broken up into smaller bubbles & be dispersed thru out the system even more..."

OK now we're cooking, great info, learned something new today, Thanks.

Just an aside, I think you may have Trevor and tm3912(me) mixed up, if I'm wrong sorry.

Doh... I did sorry TM... what a day.. I must stop sticking me nose in...

Anyway, my apologies still ride to anyone I offended...

Glad to have assisted TM'

Take care & again, good luck with it..

Joe

Most assisted brake systems that I have come across in the US have the vacuum assist unit directly behind, on the engine side of the firewall, and actuated by the pedal.

The master cylinder is usually bolted to the vacuum unit and is operated with a short push rod.

As to examples. Most folks who work on brakes without any background don't realize that absolute cleanliness is required insofar as a speck of grit could damage a component leading to unexpected failure of a new ("But that is a new cylinder" syndrome) component.

I have watched folks, indeed argued with a friend, about holding brake pads with greasy hands which then effects their braking effect.

Cleaning materials, solvents, are also important to consider insofar as some of those will cause brake line rubber to deteriorate leading to a burst line under pressure, i.e., when a brake system is being applied, and a possible collision.

Want me to go on? After all this OP was testing a master cylinder by sticking his presumably greasy fingers into the cylinders ports; leave aside the general futility of such.

I have no problem with "amateurs" fixing brakes or anything else on their cars providing they evidence some skills and knowledge. Indeed, as I get older and seek "professional" mechanics on occasion to fix something I no longer wish to tackle all too many of those (My guess is 90%) are little better than ignorant rank amateurs.

Technical issues are not issues of optimism, not at least when they can cause great damage.

Skilled and knowledgeable folks on this web site ought to consider and most of them do, because the site is open to all, just who they are advising based on what the OP may be saying.

j.

I do agree with jack asto cleanlyness is next to godlyness but for putting your fingers into an open port of a valve does not properly test the valve but fluid movment is the proper testing the shadetree mechanic like the op would not have access to the proper tooling and testing equipment to handle and determine the outcome of the master cylinder and therefor a plug and play change would be the recomendation change the master cylinder unit and bleed the system if no fix seek a licenced mechanic to power bleed the system and check the other components of the system the check is free the power bleed cost $35.00 at my shop.

GA, as expected.

My guess as to why Sears did not allow master cylinder to be checked was because then they could no longer stop their highly trained technicians from putting oil in the master.

I wasn't referring to customers who came in to have their vehicle "checked out." What I was referring to is those who came in for an oil change. The things that were checked were more of a courtesy check that came along with the oil change and it was plainly listed on the ticket what was checked. I think that maybe the reason we were required to perform a 21 point check was to identify any additional work that Sears might be able to do for the customer if it was needed. Batteries, air conditioner, tires, wipers, air filters, lights and the like were checked. Brakes were not part of the deal.

G'day Keywalker.. Fair comment on the 21 point inspection sheet. If the customer knows what is being checked & the brakes are not mentioned that is fine.

Looks like Sears only offer an 'Ancillary; service. As long as the guys can identify safety issues when they are under the vehicle dropping the oil etc; this is also a key point in early detection. Signs of paint peeling from brake lines & valves usually indicates as slight weep of brake fluid. Brake disc which have an excessive amount of scoring or grooves in them could be a sign of the brake pad is worn out or there is a caliper fault....

Cheers Keywalker... will catch up again

LOWIQJO

Try spraying some WD 40 on all the vacuum line connections with the engine running at idel. If the Rpm increases you have found your air leak! Fix it and repeat said process until there are no more leaks.

Then, check if you have power brakes and proceed as instructed in my other posting.

Get a repair book! It might help!

Air must have been trapped in the sysem. Please bleed well. check for leaks. check for wheel cylinders too. It appears the pedal is spongy.

Use reccommended brake fluid.

A modern master cylinder is a complex single cylinder pump. The piston in the cylinder has is built with two pressure cavities. Check valves letting fluid into the cylinder from the reservoir. Fluid enters the cylinder when the foot is released from the pedal. It takes a rapid push to close the check valves between the reservoir and the cylinder. It is easier to diagnose hydraulic brakes when they are hooked up in the car than out on the bench.

When the master cylinder plunger is pushed, the piston moves forward and the check valve closes. I've found that if a rapid hard movement creates pressure and a slow constant low force stroke allows the plunger to move to the end of stroke that it is this check valve that has gone bad.

The best way to bleed brakes is with a vacuum pump. This tool works with ABS systems. Most auto parts stores sell one with a reservoir to collect the fluid. Attache it to a brake bleeder, hand pump it until there is a vacuum, open the bleeder valve. Watch for air bubbles entering the brake bleeder reservoir. With no bubbles, the line is bled. Due this at all four wheels. Then do it again. Continually shut off the bleeder and top of the master cylinder reservoir. If it ever goes dry, you have to start over.

As stated, the brake system is not that complex a system to diagnose.

There is a column of fluid inside that master cylinder. When someone pushes that brake pedal to the floor, that column of fluid HAS to go somewhere. If you bush that pedal to the floor ten times, there should be a puddle of brake fluid somewhere. OR the fluid level in the master cylinder did not drop. IF you bled the air out of the system, there are few choices.

1) Did a part fall off of the rear wheel cylinder, allowing it to expand, and then retract? Once, twice maybe, but by 10 times. you would have bottomed out that wheel cylinder against something, or pushed that piston and seal right out of the bore, dumping fluid all over the floor.

2) if the front wheel bearing was very bad, allowing the rotor to push the brake piston back into the caliper, 3-4 pushes on the pedal would bring the rotor back into the correct location, followed by a firm pedal after that.

Please try pumping the master cylinder ten full stroked in quick succession, and let me know.

If you can not get a good hard brake pedal DO NOT DRIVE. Test and learn, but be safe. good luck.

Bob C,

"As stated, the brake system is not that complex a system to diagnose."

Go back and read all that you have said about brake systems.

Consider also the knowledge not explicitly expressed but implied behind all what you have wrote.

Do you still insist a "brake system is not that complex a system to diagnose."

j.

Every day the automotive brake systems get more sophisticated, and complex. But the op was not trying to discover why he had premature wheel lockup on the right front wheel when turning left. He just wants to know why he does not have a normal brake pedal. Ten good hard full pumps of the brake pedal will tell someone a lot of information if one takes the time to look. If the master stays full after that, There has to be some movement that is springing back, or there is air in the system. If the master fluid level goes down noticeably, there has to be a leak. You may not be able to see it, but you still have a leak. The column of brake fluid has to go somewhere when you push that pedal down. Do it 10 times, and there are going to be some clues.

I still contend that reasonable people should be reasonably to detect simple mechanical problems, with reasonable help. We are all seasonable people here I hope.

If you think I sent the OP too far, your opinion should be stated. Because it is the balance of opinions that makes this forum so good.

Thanks for your thoughts and comments.

Sorry, welcome to the insanity. Enjoy the ride.

G'day Jim C... good work with the video.. It is feedback & responses like yours that make it worth while doing a post.

Cheers for now & take care.

LOWIQJO

Jim C. GA. The video tells it all.

I used to bench bleed after rebuilding master cylinder and minimize the in car bleeding time. The syringe tool would save even more time.

Ok a quick update. I bought a brake bleeding pump. (hand pump) I used it on the back brakes and everything went fine after I got the hang of it. I then moved to the front brakes. I don't know if I did something wrong but on both of the front brakes there was massive air mixed in with the fluid. I emptied the (not emptied but lowered) the fluid in the MC reservoir 4 times (about 3 oz each time) and there was just as much air the last time as the first. Of course the first thing I thought was that I was doing something wrong but I reread the directions again and I was doing it correctly.

So of course I'm taking it in, IF, and that is a big if, I did it correctly that means I have a major leak somewhere (even though I don't have fluid dripping or leaking anywhere that I can see.) I still think I did something wrong but I can't figure out what it could be, especially after having done the back two brakes with no problem.

Anyways I just thought some of you might like an update, I always do when there is a mystery. I'll let you know what the experts say.

G'day TM3912.. thanks for the update mate...

God these things can crap you sometimes can't they?...

All things being equal the fronts should have bled like the rear wheels.. If you are having no external leaks & there is still air evident after that type of bleeding process, it might be a faulty new M/cyl? these have two circuits in them.. a rear wheel one & a front wheel one.. just a thought.. But please do let me know what the brake guys say...

Good work with your persistance in this matter.. I know a lot of people would have given up, but I like your tenacity, shows good character in a person...

Cheers TM..

LOWIQJO

Good answer, though if I recall correctly the master cylinder was replaced with a new one at the beginning of this exercise.

Doesn't sound like the fluid has been let get to low, no leaks detected so its looking like a leak at the bleeder screw.

Now that is a problem that using positive pressure onto the top of the reservoir fluid does not produce !!

You are right. And the chances that 2 master cylinders were bad the exact same way when one was brand new or fresh rebuilt do not sound likely to me either. Shop time.

Great first post! Please let us know, when the car is back on the road and safe, what the problem was.

Lyn

Tow truck is here as I type will let you know. I talked to the mechanic and he had a couple of idea that I didn't know/think about but will update when he fixes. Thanks to everyone for the help and suggestions.

I do not recall any mention of replacing anything, but the master cylinder.

"a special tool to return the calipers to the fully retracted position."

Or a C-clamp. I don't think there's any way to install new pads WITHOUT FIRST retracting the pistons, not calipers as you stated. How would you get the new, thicker pads in place without first doing this????

I did use a C clamp! Old trick from my father in law. And you are correct I never mentioned it, my fault!

The plot thickens! What else did you not tell us?

Bye.

Thanks for the clarification. I was intending to differentiate between disc brakes and drum type since both have pistons but only one will have a caliper with a piston.

This was a case of noticing what was missing from the dialogue, and experience.

Sort of like the older golfer hitting from the bunker and into the cup, eliciting a "wow you are so lucky" from the younger golfer, whereupon the older golfer stated "yes, it seems the longer I golf the 'luckier' I get."

Regards, CJM

"Calipers do not have return springs. If one or more of the calipers has enough gap between it and the brake pad, then you could have brand new fluid and all new parts with no air in the system, and still get the pedal to go to the floor."

Excellent analysis, the first thing my mechanic mentioned. I think you are correct. I did not change the pads out but did take them out to inspect and did retract one of the calipers pistons to make it easier to get the caliper back on. I forgot to mention this until you brought it up. Probably another mistake I made! Oh well this has been fun (most of it) there are some very smart people on this site!

I just thought you all might enjoy this. When I talked to my mechanic I told him I was going to tow it to his shop. He said, "oh don't waste your money you can drive it" Even after all I told him was wrong with it he said he would drive it to the shop without worry, just to take it slow. I don't agree with him but I thought it was funny after all of our safety issues. (Not trying to start a fight just thought it was a funny story)

When I was younger, I worked in a service station that did emergency road work. When we had a vehicle with a brake problem that the customer did not want to drive into the shop, we would always go out with one of the tow trucks and take the keys, and arrange for another truck to come back at a later time. At a later time we would return with a coworker and just drive back with out a second thought. With mostly apartments in the area, the customer usually never knew.

Earlier I mentioned ten good full hard pumps of the brake pedal. That would have seated both brake pads if that had been the problem. After ten pumps of the brake pedal if you have a leak, the master will be noticeably lower. Older Dodge 1 ton vans would hit the front caliper on hard turns if the wheel was very close to bottomed out. Just like one would get when charging out of a driveway into a road. The next time the driver hit the brakes, the pedal would go part way to the floor till the caliper was seated again. The first paramedic vehicles we purchased were 1972 Dodge 1 ton van chassis. Have a great day.

I just thought you all might enjoy this.

(Not trying to start a fight just thought it was a funny story)

WOW - please visit again, but pleeeeze be more descriptive & inclusive of what you describe.. at one point in reading this.... I was waiting for the Napalm to start flying

Take your time and always try to help those, who may help you