The Stovebolt Site Forums The Shop Area Engine Shop 41-46 Rear Brakes sticking

I seem to have discovered a problem with my rear brakes. I have the original Huck brakes on my truck (rebuilt) and have noticed that after driving the truck for several miles (15+ miles) with several stops; that the brakes tighten up pretty solid and tend to not want to let off essentially locking the rear brakes. After it sits a while the pressure does tend to free up.

Anybody have any idea what may be causing this or have any suggestions as to what I begin to look at? As I noted above, they are completely rebuilt and I am pretty sure they are together correctly.

Just back the adjustment off a couple of clicks. When the shoes rub, they heat up and expand until they actually start dragging. This happens to me everytime I do a brake job on my big trucks. I carry a brake spoon with me on my road test to avoid over heating the shoes,
Scott

I did a brake job on a 46 ½ ton and had the same problem. I did as Scott suggested, but it still would lock up after a few miles. Only the rear drums would lock, but not the front. I re-bled the brakes and still….
I noted that I had good pressure exiting the cylinders during bleeding. I checked the freedom of the shoes, back-plate spacing, new wheel cylinders etc. So what caused the rear brakes to lock up? Turns out the brake hose over the axle was partially plugged. It would allow the brake fluid to run to the cylinders, but prohibited the fluid from returning back to the main cylinder. Turned out to be a inexpensive fix, but well worth the money. Check fluid pressure during bleeding, and note the speed of return to the main cylinder. It is a balance. Let us know what you find out.

Dale

Hi Tim, Looks like Scott and Dale are right on the money.
I would try the back off route first.

I had a similar problem a few years back with a VW Bug. One of the flex pipes was working like a non-return valve.
As Scott said watch out you dont 'cook' the linings or drums!
Good luck.

Jock

This summer I had a similar problem on the front of my 52. I relaced the flex lines and problem solved. Apparently the lines can deteriorate on the inside. Mine looked fine on the outside. This the first time I ever ran into this problem.

had this problem on a 37 car on mine it was the master cylinder. inside the master cylinder the compensation port was plugged shut, I kind of had one front and one rear that wouldn't release very well

Had the same problem on my 37 several years back. Same thing, the return port in the master cylinder had some trash in it. Cleared it out and no problems after that.
Joe

Had the same problem on my 40 and it's master cylinder. I found that backing off the adjustment on the connecting rod helped.