UPDATE. Got some more time today and here's what I found. Took the car for a ~15 min drive (colder out then last time). Got home quickly jacked up the car and tried to spin the front wheels. They were tight but not as tight as last time. Cracked the bleeder on the front driver wheel and some fluid did come out (not a flood or squirt, just oozed out). Pulled the wheels. Drums were very hot, wheel bearing housing not (so don't think its anything with the wheel bearings). Checked the pads, smaller (less friction surface pad) is forward on both sides. Left the drum off one side got in the car a gently pumped the brake a few times (not a full stroke since I didn't want to blow out the wheel cylinder). Got out inspected and sure enough the pads were not returning to position. Gave a little push to see if the springs weren't strong enough, and no movement. Cracked the bleeder on that wheel and could watch the pads move back into place. So seems like the fluid isn't being released somewhere. Normally I would have thought Master cylinder, but last year when I had the prob that's the first thing I replaced. Id like to think I didn't get one bad out of the box, but I guess its possible, epically since its at both front wheels (haven't checked the rear). So what do you think, replace the master again? I wouldn't think blockage in a hose, (unless it was at only one wheel), although I guess it could be something in the line between the distribution block and the master.... Really hate ripping apart what I just finished. Thoughts?
69 RR Brake issues - Help needed
- Thread starter a6t9vette
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Basketcase
Keeper of the Green
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after working in the parts dept of an IH dealer for nine years, and 30+ years messing with cars...just because a part is new doesn't mean it's good. especially nowadays.
69hemibeep
Sponge Bob Square Wheels
On your backing plates there are 4 spots the shoes ride against that will wear causing an edge that will hold the shoes out. They can be ground down and a film of grease applied
Sounds like the adjustment or lack of free play on the master cylinder. If the master cylinder piston doesn't retract to the position that allows the brake fluid to back flow into the reservoir it won't let the wheel cylinders return either. Just a thought.
If you haven't replaced the rubber brake flex lines from the body to the drums (suspension) then you should. This cost me a left hip on a '72 BMW 2002 that I restored back in '86. The rubber flex line from age swelled down or restricted the fluid so much that I had more than enough master cylinder pressure to push the disc caliper pistons on but so much flex line restriction that the pistons wouldn't return. Locked up the front caliper and spun me into on coming traffic, steered it back and clipped the corner on a car in my driver's door that pulled off of the road shoulder into my lane that forced me to jump on the brakes hard in the first place.
Any restriction in the system (lines, reservoir return) will not let the wheel cylinder or caliper pistons return. When you opened the wheel cylinder bleeder did you have to do only one or both to get the shoes to return?
If you haven't replaced the rubber brake flex lines from the body to the drums (suspension) then you should. This cost me a left hip on a '72 BMW 2002 that I restored back in '86. The rubber flex line from age swelled down or restricted the fluid so much that I had more than enough master cylinder pressure to push the disc caliper pistons on but so much flex line restriction that the pistons wouldn't return. Locked up the front caliper and spun me into on coming traffic, steered it back and clipped the corner on a car in my driver's door that pulled off of the road shoulder into my lane that forced me to jump on the brakes hard in the first place.
Any restriction in the system (lines, reservoir return) will not let the wheel cylinder or caliper pistons return. When you opened the wheel cylinder bleeder did you have to do only one or both to get the shoes to return?
Ranger
Well-Known Member
:yeathat: Don't overlook the possibility of an internal line collapse acting as a check valve. Not real common and I have never experienced it, but have heard of it.