Rear Brake Problems

[Wrenchbender Ret]

Where are the emergency brake parts? If the cables are adjusted up to tight or sticking they will cause this but I don.t see any.

[kxnomore]

I would guess those are the wrong shoes. I had the same problem with the brakes on an Eaton HO 52, and it took 3 tries at Napa to get the right ones.

The place where the pushrods for the brake cylinder slides into needs to be bigger. They should slide right in easily.

Did you keep the old shoes? if so, check them for the exact same dimensions. Mine were off just like yours.

Good luck.

[Cheyenne Supr]

Hey guys,
I found the problem and thought y'all might want to know what it was. All the parts I had were correct; shoes, wheel cylinders, push rods, springs, etc. I had already loosened up the cylinder bleed screw and pushed the rods all the way in, bled the lines, assembled and drove the vehicle, but the shoes locked up on the drum and would not release...I could barely get the drum off. I figured I had gunk in the brake lines and tried to vacuum bleed the system with 25 lbs of pressure, but I could barely draw any brake fluid so I knew something was wrong with my lines. At that point I began to take off lines one at a time and blow them out with 90 psi air pressure. What I found was the rubber brake hose at the passenger rear wheel had collapsed inside and was acting as sort of a check valve. It would let a very small amount of fluid out to the shoes, but nothing could return back through so the shoes would not release. The hose looked fine outside, but was almost completely plugged inside. With a new brake hose and clean steel brake lines it works like a charm!
Thanks for all your ideas. They did help me to brainstorm!
Larry

[68gmsee]

Originally Posted by Cheyenne Supr

..... I had already loosened up the cylinder bleed screw and pushed the rods all the way in, bled the lines, assembled and drove the vehicle, but the shoes locked up on the drum and would not release...I could barely get the drum off. I figured I had gunk in the brake lines and tried to vacuum bleed the system with 25 lbs of pressure, but I could barely draw any brake fluid so I knew something was wrong with my lines. At that point I began to take off lines one at a time and blow them out with 90 psi air pressure. What I found was the rubber brake hose at the passenger rear wheel had collapsed inside and was acting as sort of a check valve. It would let a very small amount of fluid out to the shoes, but nothing could return back through so the shoes would not release. The hose looked fine outside, but was almost completely plugged inside....
Larry

That's a fairly common problem and it has happened to me before. But the culprit, in my case, was the rubber brake hose that's on top of the rear axle.

What's confusing in your case, and the reason no one suggested the hoses, is that you had loosened the brake cylinder bleed screw. That should have easily seated the shoes...

[Cheyenne Supr]

Yes, mine was also the rubber brake hose on top of the axle at the passenger side rear wheel.

I think I probably had the shoes seated after initial assembly (or close to it, at least enough to get the drum on). Then they locked up after I drove it and would not release. It made it seem as though the push rods were too long but I was pretty sure that was not it. I didn't want to just open the bleed screw and try to seat the shoes, knowing they would lock up again because I hadn't determined root cause. That's when I began going through the lines and doing process of elimination.

Larry

[68gmsee]

That makes sense... It's the identical problem that happened to me many year ago. There was enough pressure with my power brakes to force the fluid towards the cylinder but no enough with the spring tension to reseat them.. Wasted a whole weekend trying to figure out what was happening.

Thanks for the update.