I have a 1979 chevy k10 that has fluid reaching the front and rear brakes, but no power. I have replaced the drum brakes, calipers, brake hoses, 3 hardlines, booster and master cylinder. The only things I haven't replaced are the hardlines running from the master cylinder, and some sort of distribution block that all the hard lines start from.it makes no difference whether it's running or not, the pedal will sink to the floor and the clapiers and wheel cylinders just have no power. Any Ideas?
The "power" in power brakes comes from manifold vacuum. Check the line from the intake manifold to the booster for cracks and leaks. No vacuum means no power brakes.
even without boost, the pedal shouldn't go to the ground, don't you think?
Right Joe. It appears that the MC was not bled correctly.
I figured it out! I just had to adjust the connecting rod from the booster to the pedal
Excellent - glad you got it figured out. Nothing succeeds like success!
the block is probably a proportioning valve.
Have you tried bleeding all the air out of the system? Since you replaced everything, there will be a lot.
I bled the master cylinder before I installed it, and I bled the brakes after. although I did it by myself so there might still be some air
If you keep pumping the brakes, and the pressure doesn't build up, and there's no leak anywhere, then the problem would have to be in the MC.