Rear brake locking up

[Litchkar]

Greetings Friends,
I have a dilemma; my passenger rear drum will lock up and actually keep the car from rolling. The first time I changed the wheel cylinder, thinking it would not retract correctly. It is still having issues, where there is smoke off the wheel. I checked the temp. and it was over 400 degrees, while the driver side was under 200 degrees. I took it apart, changed out the cracked shoes, disconnected the emergency cable and lubed it in case it was sticking. When I went to reassemble it, I had to crack the bleeder to get the wheel cylinder to retract to get the drum on. Took it out for a short run, and it is still getting hotter than the other rear. 10" rear drums, SSBC front disc with a Willwood 11/8" master and adjustable proportioning valve. Connected to a Hydraboost unit. This is a new issue, and I am at a loss to solve it. I think if it was the lines to the rear, then both sides would be an issue. Could it be a second bad cylinder, or crap in the line running across the axle. Thank you everyone.

 

[Chryco Psycho]

Probably a restriction in the line , often rubber flex hoses can peel a flap inside the line & block return flow .

 

[Litchkar]

I thought that, but wouldn't that affect both sides? I might disconnect the lines at both wheel cylinders and blow air thru the rubber hose at the diff.

 

[Chryco Psycho]

You will probably need to check the flow through each line & part of the system .

 

[Steve340]

Have you checked the clearance on the master cylinder pushrod?
The master cylinder produces the brake pressure so if you are "retaining" brake pressure in the lines I would look there.

 

[Litchkar]

There is clearance with the MC. I even loosed the bolts on the MC to the booster when it locked up once and the drum did not release. I can't figure out why is only one side. Time to blow out the line to the rears, especially that side. Possibly when it cooked the shoes, it damaged the wheel cylinder. Never a dull moment lol

 

[Robert Conca]

I have been chasing the same exact problem but on a stock cuda. The right side brakes lock up. I changed shoes and cylinder and drum. Same problem. My next thing is recheck the right side steel brake line. Its only on the right rear and did not do this with the original brakes. Only started after restoring the car. I hate repro parts.

 

[hdwrench]

i would change the rubber line as they do fail ….

 

[Vinny]

Greetings Friends,
I have a dilemma; my passenger rear drum will lock up and actually keep the car from rolling. The first time I changed the wheel cylinder, thinking it would not retract correctly. It is still having issues, where there is smoke off the wheel. I checked the temp. and it was over 400 degrees, while the driver side was under 200 degrees. I took it apart, changed out the cracked shoes, disconnected the emergency cable and lubed it in case it was sticking. When I went to reassemble it, I had to crack the bleeder to get the wheel cylinder to retract to get the drum on. Took it out for a short run, and it is still getting hotter than the other rear. 10" rear drums, SSBC front disc with a Willwood 11/8" master and adjustable proportioning valve. Connected to a Hydraboost unit. This is a new issue, and I am at a loss to solve it. I think if it was the lines to the rear, then both sides would be an issue. Could it be a second bad cylinder, or crap in the line running across the axle. Thank you everyone.

My friend had this problem continuously on his 70 340 Duster, until he replaced the flex line at the rear axle. Problem solved!

 

[Robert Conca]

The rubber flex line would affect both rear brakes left & right. Your saying he had a problem on one side and the hose fixed that problem or did he have both rear brakes lock up

 

[RJH72Cuda]

I hope this helps, I work at a Dodge Dealer, When I get a truck in with this kind of problem I get the brakes to lock up, start with the wheel that is locking up and loosen the bleeder at the WC, if it fees the wheel up, repeat the process till the wheel does not fee up. That is your where you start. I hope this helps

 

[Challenger RTA]

Good advice given above. Just a thought residual value at master cylinder hanging up. Not saying that's it.don't forget about it. drivers diver side bleeds of quicker shorter. Your luck like the rest of us sucks!

 

[Vinny]

The rubber flex line would affect both rear brakes left & right. Your saying he had a problem on one side and the hose fixed that problem or did he have both rear brakes lock

The rubber flex line would affect both rear brakes left & right. Your saying he had a problem on one side and the hose fixed that problem or did he have both rear brakes lock up

I can't say with certainty if it was one or both rear brakes, but after the replacement of the master, booster, both rear cylinders, springs and shoes and the problem remained, there was nothing left but that flex line, all the steel lines and the proportioning valve. The flex was the easiest one left to replace. I doubted that it would fix the problem, but he is over the moon happy with his brake performance now.

 

[Vinny]

BTW, it was the left rear.

 

[sixpactogo]

Greetings Friends,
I have a dilemma; my passenger rear drum will lock up and actually keep the car from rolling. The first time I changed the wheel cylinder, thinking it would not retract correctly. It is still having issues, where there is smoke off the wheel. I checked the temp. and it was over 400 degrees, while the driver side was under 200 degrees. I took it apart, changed out the cracked shoes, disconnected the emergency cable and lubed it in case it was sticking. When I went to reassemble it, I had to crack the bleeder to get the wheel cylinder to retract to get the drum on. Took it out for a short run, and it is still getting hotter than the other rear. 10" rear drums, SSBC front disc with a Willwood 11/8" master and adjustable proportioning valve. Connected to a Hydraboost unit. This is a new issue, and I am at a loss to solve it. I think if it was the lines to the rear, then both sides would be an issue. Could it be a second bad cylinder, or crap in the line running across the axle. Thank you everyone.

400 degrees certainly did no favors to anything in that wheel. I would replace that wheel cylinder for sure. Probably what caused the problem to start with. If the rear hose has not been replaced recently, I would replace that too.

 

[BSG]

I had that same problem years ago. it was a front disc conversion, rear drum. Same problem, would build up pressure and drag. Long story short thing drove me crazy. Ended up going to the parts store and ordered a couple different masters. Turn's out one one version maintained pressure in the rear for one reason or another. One of the wise long timers should know what I'm talking about.. I chased that problem for a minute, was happy as sh** when I fixed it. it was like the last thing to keep it from driving after a 7 year build. I think the masters were $40 bucks a piece. I was just done wanted it fixed so I just started throwing parts at it. Last way your supposed to do it and in had tried the diagnosis tree.... good luck

 

[convdart440]

This might sound stupid but do you have the shoes oriented correcty on that one wheel. One shoe having more material bonded to it than the other shoe? Process of elimination .Did you have the drum turned after it got that hot? You might want to check out the T on the rear end it might have crap stuck in there or severely corroded. You said you have and adjustable proportioning valve , did you check the original one to see if it was bad?

 

[bc3j]

I had a hot rear drum after a rebuild and it was the Chinese made drum was out of round. Turned them both which solved the problem.