4 Wheel disc conversion issues

[jusbadcj]

I have a GM power booster / corvette master / not sure about the prop valve. I cant get the rear calipers to work. They move just a little, but thats it. And the parking brake moves, but not enough to work. It has the screw out pistons. 80 olds toronado. I've read so much, I dont know what to do. I need rear brakes! Any advise would be greatly appreciated...

 

[Old Dog]

I have a GM power booster / corvette master / not sure about the prop valve. I cant get the rear calipers to work. They move just a little, but thats it. And the parking brake moves, but not enough to work. It has the screw out pistons. 80 olds toronado. I've read so much, I dont know what to do. I need rear brakes! Any advise would be greatly appreciated...

If the prop. valve isn't new I'd get a disc/disc one and try that.

 

[Old Dog]

When you bleed the rear discs do you get good pressure out of the bleeder?

 

[Purple77CJ7]

Some of the original proportioning valves need a special tool to pull a pin out to bleed the rear brakes. If I remember it is on the back of the valve. You may be able to pry it with a screw driver.

ABS Brake Proportioning Valve Depressor | OTC Tool Manufacturer for Cars and Trucks


This is the type of tool I bought and used. I took the Jeep tool number from the old repair manuals, and this was as close as I could find.

 

[paparooster]

You need a disc to disc p valve on it . my CJ5 has disc on rear but was able to use old disc to drum p valve on it . here's my setup on back of my Dana 44 dodge truck line geo tracker rotor single blade rotor chevy chevette caliper..