Power Brake Conversion Problem
 

I added power brakes to my 72 c10. I have a new MC for power brake setup, a factory bracket, pushrod, and booster. I have read that the pedal will be somewhat closer to the floor board with the power setup, so that didn't surprise me (only 1 hole in brake pedal). However, the brakes feel harder than manual. They bled up fine, and I bench bled the MC and i do not have a brake warning light. If I step on the brakes while running, the rpm's die off very noticeably. After shutting off the engine, I can hear hissing for a few seconds. Could a faulty booster be the problems? The brakes seem to work the same with the vacuum line pulled off the booster.

Re: Power Brake Conversion Problem
 

Yup, sounds like a vacuum leak. You should not hear any hissing.

Re: Power Brake Conversion Problem
 

Vacuum leak.

Re: Power Brake Conversion Problem
 

i assume with the engine dying when pushing the brake peddle it would point to the booster. The manifold fitting and vacuum tube are new. I also noticed that when I shift into gear it has a lag time. Guessing that is due to the leaky diaphragm in booster.

Re: Power Brake Conversion Problem
 

Thanks fellas, new booster came today - works much better. Brakes seem to grab all at once but they work much better. Maybe some adjusting this weekend.