I have 94 honda civic and finally had the money to swap the back drums. So did that and swapped proportioning valve with it. With the car still in pieces I bought a kit with hug brakes up front and 6 piston caliper and then decided to put in a type r master cylinder. Huge amount of work but here is the issue. Start the car no brakes pedal goes to floor but will return. With the car off if you pump the brake a few times the brakes are solid. E-brake works fine so the booster worked when i first started it. But what the hell is my issue? No leakes put in stainless braided lines. At the shop now but I don't think it is anything he is hinting at such as air in the lines or rolled the seal on the master cylinder when pumping while bleeding the brakes. Any ideas??? Please Help.

 

by the way running type r motor.

 

Bad master cylinder?

 

Possibly MC cylinder seal to booster. That is easy to check, at least in the Integra. I can pull the MC out of the booster and inspect it without opening anything, still attached to the lines.