I'm getting only air and little fluid out of the rear Proportioning valve outlet

[75LTCAMARO350]

On my '75 camaro----

I'm getting only air and little fluid out of the rear brakes Proportioning valve outlet when pressing on the brake pedal. What item is bad? the Master or the Proporting valve? Is there a way to check? My warning brake light don't work.

I bought and used a vacuum brake line bleeder ---because I am getting no brake pressure to the rear brakes. They do gravity bleed in the back, but if I try to hit the pedal bleeding ---I get no fluid!!! the proportioning valve may to bad or not properly aligned, but thought I would try the vacuum bleeder , before shelling out alot of $$$$ on a proportioning valve replacement/repair.

Any ideas are helpful---Thanks in advance!!!! Merry X-mas!!!!!

[Erics69]

Have you checked to make sure the rear flex line isn't clogged? Chances are it's not in good shape considering it's probibly original.

[75LTCAMARO350]

I do not think its the flex hose. I am getting gravity bleeding to the rear.

Now I'm not getting much fluid out of the outlet from the proportioning valve.

any ideas????

[75Motion]

Why are you bleeding at the proportioning valve? After the master cylinder is bled you would go to each wheel and bleed. I would think that by removing the line the valve assumes that there is a problem and shifts to prevent loss. If you can gravity bleed at the rear then you don't have a blockage. I would make sure the system is closed, all lines tight and all valves closed, check the fluid level in the master cylinder then bleed ther rear brakes then the front. Get a helper that can follow instructions of pump and hold.

[Erics69]

Just because the rear lines gravity bleed doesn't mean the lines are clear. If the flexline is clogged you still have plenty of fluid left in the rear lines to leak for days or up to a week. But I do agree with 75Motion when he questions why you are bleeding the prop valve. It probibly confuses the prop valve into thinking there is a leak.

[75LTCAMARO350]

I tried bleeding the proper way for the last month . I tried the pressure bleeder and all. Now I am trying anything.

Agreed might confuse the prop. valve. thanks!!! merry x-mas

[ronzz572]

make shure shoes are on correctly and adjusted all wheel cylinder pins are on shoes and also there are no loose or open brake lines. might be sucking air from rear of mastercylinder