90 Mustang 5.0 brakes-no indication if no pressure to rear brakes

I have a 90 5.0 Mustang. I apprently have been driving it two years with no rear brakes. I have changed the shoes, drums, and wheel cylinders and bled the system. I suspected something was wrong in wet weather braking and then when I was getting the emmission tested wtih the rear wheels on the dyno, the tech said I had no rear brakes. So after more work, I put the car on stands and verified this. The brake light only comes on for a loss of fluid or for parking brake set. There is no lost pressure sensing to a warning light from the master cylinder or the proportioning valve. In my case, I am sure the master cylinder is bypassing fluid at the rear brake piston. Does anyone know of a retrofit. I have checked part numbers through 93, and they are the same. The 94 (new body style) has a more simple master cylinder with just one port for the front brakes, but I don't know if it uses a different proportioning valve with a sensor and I don't know if a 94 master cylinder would fit.

Reply to
Jim
Loading thread data ...

It's possible you have a bad master cyl. and/or porportioning valve. Could be the valve is diverting pressure to the front and the sensor isn't telling the warning light to come on. Check if you have a kinked brake line to the rear. You could have hit something. Also, if you bled the rear then that means it's getting some pressure otherwise nothing would come out.

.

Reply to
Mark

Ditto Mark!

That master cyl is way old... wouldnt surprise me if it was bad but it could also be a hung prop valve

Reply to
Backyard Mechanic

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.