1977 911 Targa
Background:
1. After sitting idle for a year, brake lines leaked and soft lines were replaced with new Braided Lines.
2. Rebuilt Calipers
Could not get a firm pedal after bleed regardless of effort and number of times. Used Vacuum bleeder, Power Bleeder and Two person method of pump and bleed.
Then:
3. Replaced Master with New Master.
Could then get a firm pedal halfway down. BUT when the car was turned on and the Booster kicked in, pedal went to floor. When car was then turned off, the pedal lost all firmness and went to floor again -- as if it was not bled just prior.
Had a local racing team mechanic recommend opening the lines at the Master only slightly under pressure from the Power bleeder. Did get a couple of bubbles and again got a stiff pedal about halfway to floor.
BUT again, turn car on, Booster kicks in, lose the pedal!
I have gone through this procedure of bleeding and regaining pedal, to only lose it when Booster is on too many times to count.
I have bled the lines at the Calipers each time and do not see any air coming out.
I do not see any fluid leaks and fluid levels are solid.
I am starting to believe that something is wrong with the new Master but am stumped as to what could be wrong. If it was not the master, I believe I would see bubbles at the calipers.
Had another racing team "brake expert" suggest that the diaphragm on the booster is possibly torn, which would explain why it would be sucked to the floor when it kicks in, but does not explain why the pedal does not recover when Booster is off.
Anyone have an experience like this or thoughts in general on the problem?
