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Wed Jun 23, 2004 8:56 pm

my left front brake sticks every once in awhile. I have bleed the whole system, put on new soft lines and replaced a leaky wheel cylinder on the left side. My brake will stick and then after a while it will stop. This morning it started to stick and and never released. I made it to work parked it. Later in the afternoon i went to check it and it was unstuck. The pressure was released. Could it be my other wheel cylinder that i did not replace? I have plenty of pedal play also. This only happens once in awhile and this is the longest its lasted. About 25 miles. :?

Wed Jun 23, 2004 11:35 pm

Other than a thorough cleaning, have you replaced the return springs? How do you know the left is sticking? Sweet smell of burning brakes on the left (or smoke) or did the wheel get hot?

Thu Jun 24, 2004 6:35 am

dstefun, the brakes smelled hot and the wheel was hot, i can also feel the left side hanging up when i take off.

Thu Jun 24, 2004 6:48 am

Is there any free play when you move the brake pedal by hand? There has to be alittle or the bumps in the road will slowly pump up your brakes while you are driving.Usually this will pump them all up but maybe the front left is adjusted up alittle tighter than the others. I would also pull the drum off and look at the way the brakes are put together on the left versus the right to see if it is correct and check the return springs like the previous post suggested.

Thu Jun 24, 2004 7:44 am

I've had this problem before. Did you use a Brazilian dual circuit master cylinder by chance? If not, this may still apply.

What seems to happen, is the fluid doesn't drain back to the resivoir and instead starts to boil from the friction of the dragging wheel cylinder. When the fluid boils, your brakes lock up tighter and tighter.

Pretty soon you're calling your boss telling him "I'm going to be late cause my brakes keep locking up and I have to pull over and let them cool down"...don't ask. :) What I ended up doing was replacing it with a german F.A.G. M/C and all was fixed.

It can also happen if there is sludge in the bottom of the resivoir because fluid will be slow to return. A crimped brake line can also cause this or internal rusting that leaves the steel lines clogged. Try flushing the hot wheel cylinder's line. And Yes, a wheel cylinder on the opposite side, or anywhere in a single cylinder circuit will have an effect on another wheel cylinder. You might be able to get rebuild kits from Napa and rebuild them yourself with a brake hone and drill. I've done it with Bettle items and its not so bad.

-Bobby

Thu Jun 24, 2004 12:51 pm

TimGud wrote: Is there any free play when you move the brake pedal by hand? There has to be alittle or the bumps in the road will slowly pump up your brakes while you are driving.Usually this will pump them all up but maybe the front left is adjusted up alittle tighter than the others. I would also pull the drum off and look at the way the brakes are put together on the left versus the right to see if it is correct and check the return springs like the previous post suggested.

When I replaced the master(FAG Single Circut) on my 59 I had to shorten the pushrod a bit so I had the proper gap between the rod and the MC piston.

Thu Jun 24, 2004 5:54 pm

57dbldoorpanel wrote: the brakes smelled hot and the wheel was hot, i can also feel the left side hanging up when i take off.

Regardless of the cause, at this point you need to pull that side down, turn the drum, and at minimum replace the return springs, rebuild the wheel cylinders, repack the bearings, and of course bleed and adjust the brakes. You might be able to save the linings but IMO it's false economy - replace them too. If it got hot enough to give you a hot wheel that's a major brake hang up. I agree with VWBobby - the steel lines could be rusted internally. While you have it apart make sure they are flowing freely. Good luck! :wink:
Dave

Thu Jun 24, 2004 5:56 pm

May want to replace the rubber brake hose. I was told they can collapse on the inside and block flow returning from the wheel cylinder.

Thu Jun 24, 2004 6:14 pm

edgy wrote: May want to replace the rubber brake hose. I was told they can collapse on the inside and block flow returning from the wheel cylinder.

That was one of the first things I thought of too, but he said he has already changed them (put on new soft lines) in his first post.

57- you said you replaced a leaky wheel cylinder on the left - did you rebuild the other one at the same time?
Dave

Fri Jun 25, 2004 12:13 pm

57- you said you replaced a leaky wheel cylinder on the left - did you rebuild the other one at the same time?

I did not rebuild the other cylinder when i changed the leaky cylinder. I also noticed when i was checking under the bus that i lost an upper shock bolt on the right front.( the problem is the left front) The shock was laid down on the soft line pretty hard. Would that do it?? I removed the shock and bleed the brakes before i left work and had no problems on the 30 mile drive home.I will be getting into the brakes Monday. Thanks for all the advice guys.

Fri Jun 25, 2004 10:06 pm

57dbldoorpanel wrote: 57- you said you replaced a leaky wheel cylinder on the left - did you rebuild the other one at the same time?

I did not rebuild the other cylinder when i changed the leaky cylinder. I also noticed when i was checking under the bus that i lost an upper shock bolt on the right front.( the problem is the left front) The shock was laid down on the soft line pretty hard. Would that do it?? I removed the shock and bleed the brakes before i left work and had no problems on the 30 mile drive home.I will be getting into the brakes Monday. Thanks for all the advice guys.

if the fluid can't go back to the MC the brakes will drag. Ya I've had old brake flex hoses do this. Did you know that the idiot book doesn't mention their existance? Then eventually the tumours start, and it can pop... look ma no pedal!!! You can put a vise grip on it for a short drive tho :wink: BTDT (short version of story) How's your hand brake?

It the shock mashed the brake line, yup it could mess it up. check the line... if it's damaged replace it... or it could burst (look ma no pedal!) if it's twisted it can also impede flow. Or if if was installed funky (should have keeper) and rubs that's bad... you don't want anything rubbibg through the line.
huh..but the shock wasn't on the same one as the sticky brakes... so that wouldn't make a different side stick anyway.

don't replace one front cylinder... replace all on the axle... yes all 4 fronts or both rear as the case may be. when checking for leaks.. pry back the dust cover... it should be dry inside.. it's a dust cover to keep dust out of the cylinder... the fluid seal is inside on the piston. So if it's wet inside the dust cover the cylinder is leaking, even if it hasn't got to the shoes yet. And do the front hoses have the keeper things that are bolted to the spindles.. they keep the hoses from rubbing on things and wearing through.

good idea to flush the whole system every year or two... if the fluid in your MC is dirty, do it... I wipe the gurk out of the reservoir too. Clean
brake fluid means longer brake parts life.

do all four wheel bleed vigourously?.. I mean, does the pedal pusher have to push hard when the valve is open... if they do that meanseither the valve isn't open enough or there is a blockage.

Fri Jun 25, 2004 10:38 pm

i had a similar problem on a bug. the culprit was the pushrod. :)

Sat Jun 26, 2004 9:27 am

dstefun wrote:
57- you said you replaced a leaky wheel cylinder on the left - did you rebuild the other one at the same time?
Dave

You should ALWAYS do the same thing on both sides of your brakes. Otherwise you're looking for trouble down the road. You should go back and replace the other cylinder.

JP