Brake problem, not supra but toyota family

[keo]

having brake problems with my 95 corolla daily driver.

I drive about 30mins, the front brake and back locks up. park and sit for 30mins. am able to drive again for another 30mins.

Change Proportion valve(used), New (calibers, pads, rotors, brake booste, master cylinder and 2 front brake hose).

Still same issue, what can be the problem?

thanks for your help,
-keo

 

[whitemike]

You didn't check your ABS unit? It has ABS im assuming

 

[keo]

no abs on the car,
im gonna try to get a few proportion valves at the junk yard. to see if the used part is the problem.

anyone else with ideas.
thx again,
keo

 

[toyotanos]

Did you set the booster pushrod to master cyl piston clearance? There's a special tool you need to use to do it. Otherwise it can hold the master slightly pressed in, which holds pressure in the hydraulic circuit. That's the first thing I would check, I've seen it too many times.
Also, is it a brand new Toyota master cyl? I've had bad luck with aftermarket masters in the past.

 

[keo]

thx, i adjusted the pushrod near the pedal. Did some driving so far so good.
No brake locking after an hour of driving.
thanks again for your help.
-keo

 

[toyotanos]

The pushrod I was talking about is in between the brake booster and the master cylinder, which has splines and a locknut (needs a special tool to measure and adjust this) but it sounds like your adjustment was enough. Good job!

Guaranteed way to diagnose a master holding pressure would be to crack a bleeder and see if the wheel spins after. Congrats anyways, these corollas are awesome DD's.