300winchester

I am not getting fluid to rear brakes, How do you reset the proportioning valve ? the fronts are fine, Please let me know in detail how to do this if you know. Thanks in advance for your help

dintymoore

I don't think there is any "reset" on that valve. I've never touched it and done brakes on several of these cars.

If you've opened the bleed screws enough (at least one full turn or maybe a bit more) and no fluid is coming out either of them , I would suspect either you need to keep pumping because there's a column of air in there that needs to come out first, the wheel cylinders are frozen on both sides (unlikely but not impossible if they're original) or more likely the master cylinder is bad or was never bench bled properly.

I'm gonna guess on a bad brake master cylinder.

300winchester

Well, very interesting, when I bled the fronts and then tried the back I found out you could NOT pump the backs to bleed, you had to just hold down firm on the pedal and not pump while someone opened the bleed screw. Worked perfect, got all the air out and back in busines.

dintymoore

There's something wrong there. The rear brakes on these vehicles are near identical to every rear brake GM has made in the last 50 years.

If you open the bleeder screw on a rear wheel and pump your brakes and no fluid comes out, I would suspect the rear wheel cylinders are not working correctly.

Keep in mind that your front brakes provide the vast majority of braking power, so I suspect that your rear brakes are hardly, or not at all, working and you're running on your fronts only... not the safest.