Shade Tree

iTrader: (1)

When I bought this 80 model RX7, the brakes were terrible, it had been sitting for a few years. So I replaced the master cylinder, new rotors and pads. The calipers are working fine as the front brakes will stop the car. The problem is I have bled the back brakes until clean fluid is coming out with no bubbles, but they will not pump up at all. When I have someone push down on the pedal and hold it, very little fluid comes out with very little pressure. With the drums off, the shoes dont move at all. I have no leaks anywhere. Could the proportion valve be bad and not sending pressure to the back brakes? When I bench bled the mc, the port for the rear didnt seem to push fluid as fast as the port for the front.

Shade Tree

iTrader: (1)

I now have the rear brakes working. It was the proportioning valve.

Eduardo Santos

Nice one on finding that one by yourself!
Anyway, on those situations it could be a clogged tube somewhere in the path to the rear brakes, brakes poorly bled, or the proportioning valve as it was in this case.

Cheers!

RxManny

Good...glad you got them to work