Front Brake Line

Front Brake Line

Front Brake Line
No fluid at either front brake bleeder. ?

Replaced both front rotors, discs, and calipers. I have no fluid coming out of either front caliper bleeders when bleeding front brakes. Not even if completely removed. Of course, this is when peddle is pumped. Fluid also drips from line at master cylinder when removed. Also, fluid does drip from brake line at caliper when removed. Rear wheels do have fluid and bleed ok. Back brakes do work. What to do?
This is a 1973 Chevy PU C-20

I always enjoy reading the answers from people who don't have a clue. I am not sure why some people make wild guesses.

Your 1973 c-20 uses what is called a proportioning valve. This serves 2 purposes. It allows the front brakes to engage before the rear brakes to allow more even braking. It also serves another purpose, to protect the system from total fluid loss if you should rupture a brake line. Say you rupture a line in the front, the valve will shift blocking any more fluid from going to the front, so that you still have rear braking.

What has happened is during your brake job you did not allow the calipers to gravity bleed before attempting to a pedal bleed. This allowed the proportioning valve to shift to block fluid from going to the front. In other words it was responding to a perceived drastic fluid loss.

You are going to have to get the proportioning valve to center again. This can be tricky. You are going to have to find the proportioning valve. It is basically a block with the brake lines running to it from the master cylinder. It may have a one wire switch going to it. Sometimes they are on the frame. Other times they are near the master cylinder. Once you find it, open a brake line off from it that goes toward the rear brakes. Have an assistant slam on the brake pedal really hard. You are trying to simulate a drastic fluid loss to the rear brakes. Then tighten the line. See if that centered the the prop valve.

An alternative is to simply replace the proportioning valve and gravity bleed the system. By gravity bleed I mean just crack all the bleeder valves, front and rear, and let it set until fluid runs out on their own without depressing the pedal.