Brake system Questions

[70 RR]

Last year I decided to convert my front brakes from drum to disc. I run manual brakes brakes and I was told that I needed to run a different master cylinder and a adjustable proportioning valve to accommodate this set up.

This year I decided to swap my 8 3/4 for a Dana and convert the rear drums to disc. My first question is, can I now omit the adjustable prop valve? When I tried to bleed the rear brakes no fluid was coming through the lines but I had fluid to the front. My question is, how can I test the factory prop valve to see if it is sending fluid to the rear brakes? I am wondering if my problem lies with the adjustable prop valve and that is the reason for wanting to omit it. I have removed the adjustable valve and could testing the factory prop valve be as simple as applying pedal and see if fluid pumps to the rear? I don't have a line connected to the factory prop for the rear brakes because the line on there at the moment has been shortened when I added the adjustable prop. So because it is a nightmare to get at the factory valve due to torsion bars and headers, how would you guys attack this issue. thanks!

 

[miller]

First you need the right MC for disc/disc setup, since disc/drum uses it's own type of MC. Try to find a stock disc/disc application, to see the MC type, maybe a later model Mopar.

Even for manual brakes, getting brake fluid to the rears via an adj por valve...make sure it's OPEN. It is just a valve, either opened, closed, or somewhere between. If it's fully open, basicly like it's not even there, just an open line.

 

[70 RR]

Thanks, l am going to remove the adjustable proportioning valve because a disc/disc set up doesn't need it. As far as the master cylinder is concerned, I'll have to do some research.

 

[70 RR]

Removed that aftermarket Summit prop valve, replaced the brake line to the rear axle and problem solved....