brake question. one locks up

[18GVR4]

so i replaced the master cylinder and booster. i bled the master cylinder and the breaks a couple of times. after like 10-15 mins. of driving, the brake pedal gets rock hard and the front passenger caliper grabs tightly. any ideas? thanks. Mark

 

ABS problem

 

there are two main types of braking systems. front rear split & diagonal. our cars use the diagonal type. when you bleed u will start at the right rear, move to the left front, then left rear & lastly right front.

If you do front to rear as you would with say a Chevy nova 70's, you will pitch the proportioning valve to one side & get what your describing. try re-bleading the system first.

 

[CP]

Never had this problem bleeding from the farthest from the reservoir to the closest: RR, LR, RF, LF. I've done it this way with and without the ABS in this car and there's no difference.

 

[18GVR4]

ive been told that it is a bad hose at that wheel. he said it is acting like a one-way valve. when i crack the bleeder screw, it releases. here is how i bleed the brakes anyway.

 

[18GVR4]

well, i switched out the brake hose. still does the same thing. but after it locks up, i take off the hose that goes from the brake booster to the intake manifold, and the brake loosens up completely. any other ideas? thanks,
Mark

 

try replacing the check valve or just take an easy test drive with the vac booster dissconected & see if you still get lock up on that wheel. I would think it wouldn't effect just one wheel though. check the adjustment of the push rod, pedal to booster it may be too tight?

 

As I'm investigating a problem with my abs I triped across a symptom list that includes the issue your fighting so it may be an abs issue. Give me some research time tonight & i'll run a few idea's by you tomorrow.

 

[Breakerrr]

Any more information on this problem?

 

[89Mirageman]

I see the OP posted this over ten years ago but this is the first time I have seen it. I had something very similar happen on my 92 Colt when I upgraded to a larger booster and M/C. Took me a while but I found the issue. There is a small acorn nut on the threaded rod on the booster. When you press the brake pedal this rod comes out and compresses the piston on the M/C. That small nut is adjustable. In my case it was screwed out a little too far and it was putting light pressure on the M/C at all times. This would be equivalent of riding around with your foot barely resting on the brake pedal. As you can imagine this would heat the brakes up very quickly. After a few miles the caliper will get so hot from friction it'll try to start seizing up. Once it cools back down it returns to normal. I removed the M/C again and took some measurements. Saw that it was out too far and screwed it in a few turns and measured again. Put it all back together and problem solved. So if you replaced your M/C and booster at the same time and just assumed it was adjusted correctly this is probably your issue. Maybe not but worth looking into.

 

[OldHairyBastard]

If it's not the check valve -- Which is what it most likely sounds like it is then it could be air in your lines and that that caliper is sticking or the hardware is sticking. It's most likely a combination of both but it sounds like it is a bad check valve or the valve is in backwards.