40 ply brake dragging

[Don St Peter]

I am now beside myself on the solution of an obvious brake shoe draging on rt. rear when the wheels warm up. I've convinced myself that's problem since wheel gets real hot compared to others. I cannot adjust it out using "minor" adjustment. Once things cool off, I'm good for another few miles. I've inspected all brake shoes and wheels, resembled with same problem. I'm wondering if somehow the " major" adjustment got screwed up. Has

anyone else been there that could propose what I look at next.

Thanks

Don

[Plymouthy Adams]

are you sure your pedal is returning to the rest position..the bleed hole at the rear of the master..is it free and clear? if this is blocked there will be residual pressure in the lines, enough to cause dragging of the brakes..

[Don St Peter]

Pedal does return to rt position. Could it be the port hole even though it's only right rear that's dragging?

Thanks

Don

[deathbound]

Could the spring on the brake shoes for that wheel be broken, not allowing the shoes to retract from the drum?

[captden29]

pull the boot off of the wheel cylinder and look for rust/corrosion. my dragging right rear was the wheel cylinder. i replaced with better quality from dorman on both sides of the rear and no more dragging. alot of the replacement parts we get are from china and the quality of the metal is poor and they rust up fast. hope this helps. capt den

[Don St Peter]

Capden29 hit nail on the head. Wheel cyl "gunked" up inside. I had previously had all cylinders sleeved with stainless. Cleaned everything up and put back together. Bleed brabke system & Test drive went well with a lot of braking to get things hot with no problem

Thanks for all input

Don

[40P10touring sedan]

Oh...been there done that! If your brake adjustment is known to be good, then I have to direct your attention to your MC, especially the clearance between the push rod and the MC piston!!! My 40 did the very same thing as you described with the exception of getting a higher pedal every time I hit the brake...after afew miles my car nearly locked up the rears and had the brake lights stuck on...turned out the brake peadl push rod was riding the MC cup/piston and not fully releasing brake pressure. There's supposed to be roughly an 1/8" of clearance between the end of the rod and the piston with the pedal at rest...mine was riding right on it! Pull your rubber rod boot off or back and check for that gap with the pedal held back in the rest position...BTW, how's your brake return spring?

You didn't mention anything about a high pedal like I did so I'll also have you check your MC release ports in the reservoir to make sure they're not plugged up. You may have to completely remove the top cap to your res to get a good view of it...pulling the floor board wouldn't hurt either for full access. With that full top reservoir cap off, drape a paper towel or clean shop rag over the MC and fully push and release the brake pedal.. the fluid should almost hit the rag if it's returning well....

[TodFitch]

Capden29 hit nail on the head. Wheel cyl "gunked" up inside. I had previously had all cylinders sleeved with stainless. Cleaned everything up and put back together. Bleed brabke system & Test drive went well with a lot of braking to get things hot with no problem

Thanks for all input

Don

Sleeved with stainless and they are full of gunk? At the least, that sounds like there are contaminants in the system that should be flushed out.

Old fashioned steel brake lines rust from the inside out as DOT 3 (and the pre-DOT rated brake fluid) absorb moisture. If at all possible I'd suggest replacing all the tubing and hoses in addition to cleaning out the wheel cylinders. You'd really rather not have a thin spot on the steel piping give way under heavy braking conditions...

[K_Jordan]

Ive been having a similar problem with my 48. After sitting for a few hours the car will pull off and driveand stop fine. The first 10 times hitting the brakes it stop smoothly. But the more you have to push the pedal it seems like the front left wheel is sticking. When you apply the brakes it pulls hard to the left. Then it feels like the brakes are dragging and my tempreture gauge starts to rise. I've out all new wheel cylinders all around and new hoses and steel lines and Ive also added a 75 Mustang II MC. We've bled the brakes around 20 times or so and any type of adjustment I try to make doesnt seem to fix the problem.

[Plymouthy Adams]

if left front is sticking I would look to the rubber line first off..when cold and such you are getting fluid through as you also have pressure on your side...and a slight collasped/internal swollen line has a restricted reverse flow as you have but the brake spring pressure returning fluid to the master

[K_Jordan]

All od the hoses were replaced four months ago I hope I can remember where I bought them from

[Plymouthy Adams]

whoa on the quick idea of returning them..now AI must ask if the pedal is returning in full..I do not mean just the pedal inside the car coming back to rest but when in rest position, is the r master cylinder pistons retruning to the stop position in the master..it does not take much of a mis adjustment to give you problems..

I would carefull do an inspection of the mechanical prior to jumping back onto the hydraulic aspect..

[Plymouthy Adams]

whoa on the quick idea of returning them..now AI must ask if the pedal is returning in full..I do not mean just the pedal inside the car coming back to rest but when in rest position, is the r master cylinder pistons retruning to the stop position in the master..it does not take much of a mis adjustment to give you problems..

I would carefully do an inspection of the mechanical prior to jumping back onto the hydraulic aspect..

[K_Jordan]

Yes the both the pedal does return back full that waas one o the first things we checked for and made adjustments to make sure that it was.

[greg g]

Is there any contamination on the shoes??? If you go a bit of brake fluid or grease/oil even fingerprints on the shoes, that will sometime keep them from releasing. Have you checked that the rrelief port in the MC is clear and releasing pressure???

[desoto1939]

On the left wheel check the backing plate to make sure there is no burr on the plate were the shoes might be hanging up on the backing plate.

I have seen this happen on some older cars. I had a pulling pbm but was not leaking any brake fluid, the lining was getting harder on the shoes so I cleaned the shoes with brake cleaner and then sanded the linings and cleaned all the dust out from the drum and then also used a fiber pad to clean the inside of the drum to make sure this was clean of anything that might be there.

This solved my issue on my 39 Desoto. Some of the newer bonded lining and getting hard real fast and then the get a glaze and then the car will pull to that side.

Rich HArtung

[K_Jordan]

There isnt any fluid on the shoes. Theres just a lot of brake dust. Im will try to clean them up. A buddy of mine said that my brake shoes were to thin and said that I should just put new ones on and that would solve my problem. But I think that if I put on new shoes the wheel will really lock up.

[Californian]

I was helping a friend recently and we had a similar problem with the R/R wheel locking up we checked everthing and even after the wheel cyl. rbuild it still did it, we were in the master cylinder and i new something was wrong when the fluid did not spurt back in the M/C from the vent hole after the brakes were applied, my friend ending up taking it to someone else and they determined the M/C piston cup was in backwards and was not allowing the M/C to vent hence the brakes locking up and the brake pedal getting harder.It would release after the car set...

I had this happen years ago with My Harley with juice rear drum brakes and i had put a master cylinder on that had a rubber piston cup for Dot -3 not dot5 i put in there, and the cup expanded and a little piece of rubber got cut off and went in the brake 3/16 hard line and got stuck and the brakes would lock up, I carried a wrench with me to release the fluid pressure , then i took it apart and blew the brake line out with compresd air and out came the rubber from the m/c piston cup I went back to dot 3...

Tom (12)

[K_Jordan]

I just wanted to say thanks to everyone for the advise. I ended up replaceing the 4 month old hose on the left wheel and problem solved. My dad had mentioned changing it a while ago but I didnt think that a new hose would go bad that quickly . But Im back to driving and I hope to make my first cruise-in for the year tomorrow. Thanks again

Kevin

[Plymouthy Adams]

that is a rarity that a new hose should fail that quick..very uncommon for sure..I would have to suspect some foriegn object maybe lodge in the hose..maybe got there in the fabrication process..

[K_Jordan]

I couldnt believe it myself. BUt once I changed it there have been no issues. Ive been able to focus on some other projects that need to be addressed

[Dodgeb4ya]

Maybe it was one of those cheesy Chineasy hoses? The China replacement parts are flooding the US market. Gotta stay away from China brake and suspension parts. Not the best stuff!

Bob

[40P10touring sedan]

Well, think about it...if the hose attained some kind of leak in the inner rubber and that fluis swelled the surrounding area nearly closed, it would act like a restriction...maybe the swelling wasn't enough to be seen from the outside of the hose...long enough....I don't know- glad you got it fixed though!