Hello, A few weeks ago, I put a new wheel cylinder in my Lark. They old one was leaking. The brakes in the car used to stop very well. I could stop so hard that the car would almost stall. With the Holley carb, it would fuel slosh and die! Now, the rear wheel (where I put the new wheel cyl) locks up with just a minor touch of the brakes. Amazing. I adjusted the shoes "in" to get a little less grab, but that barely helped. What the heck is going on? New wheel cyl, and now (3 weeks later) the brake locks up?
did u rebleed both rear cylinders? could the new wheel cylinder be leaking onto the brake shoes ? new brake shoes both sides? did u adjust the other side shoes? front disk ? if front drum, no prop valve. my philosophy, when replacing wheel cylinders, if u replace one, u replace both. doubt if the prop valve is bad. i replace mine because the valve that is clamped down when u bleed the disk brake front & drum rear brake, seized.
I only changed out the wheel cyls. I WILL take your advice and change the other side. I don't think I bled the other side. The car has disk in the front. No, I did not adjust the other side shoes. I don't understand your last sentence, though....
My car does the same and pushes through the front brakes before pushing through the back (power braking). My is all 4 drum though... not sure what the issue is but good luck o No:
andrew; concerning my last sentence- there is a small valve on the original prop valve unit that has to be depressed and held (manually clamped) when bleeding the brakes, if u have disk front brakes. the instructions for this are in the shop chassis manual. also, on a disc brake (front) system, the prop valve delays the rear drums, a millisecond or two, to allow the disk brakes to activate. keeps the rears from prematurely locking up.
The prop valve can also go bad after 30 + years. Mine got gummy inside and screwed up my brakes, replaced it and all was well.
The shoes are clean. I used a lot of brake cleaner and was careful. Even still, how would brakes with comprimised friction coeficients (due to having fluid on them) actually grab even moreso than the other side (which was clean)? Dunno..
Make sure you have new brake spring hardware. If they are originals...time to replace them all. Also, make sure the rubber hose from the hard line to pumpkin T is in good condition. If it has an internal clog, it is not letting brake pressure release which means the shoes may be slightly dragging.
Hardware is fairly new. Hadn't thought about the hose, though. Good point. But, the lock up is almost comical. When I hit the pedal, that one tire locks immediately, if I let off it stops immediately. I swear I could put my own spotted line in black rubber all the way down the street.
Well a drop of either Brake fluid or Axle lube will cause the shoes to grab hard, and lock right up even when the braking is easy. possible you are leaking lube, or didn't clean the shoes well enough. I would just replace the shoes as they are fairly cheap.
gusy- had a 1981 cutlass brougham. whenever i had to brake just a little hard, the right rear would almost always lock up. gm replaced that wheel cylinder and no furthur problem.
