well sort of anyway. ong story short. Never replaced a chevy master cylinder like the one that's on my malibu,68. Problem: bled cylinder on car. Then bled all four wheels. Originally goos flow, but can spin wheels freely with pedal down. Pedal goes to floor. Continued to bleed and eventually got a pedal, sort of. Went on road test, brakes work fine even though pedal wasn't good in the air.
1. When bleeding the brakes, does the m/c cover need to be on??
2. If so, how do you keep air from being sucked in??

Originally posted by 68joker:
well sort of anyway. ong story short. Never replaced a chevy master cylinder like the one that's on my malibu,68. Problem: bled cylinder on car. Then bled all four wheels. Originally goos flow, but can spin wheels freely with pedal down. Pedal goes to floor. Continued to bleed and eventually got a pedal, sort of. Went on road test, brakes work fine even though pedal wasn't good in the air.
1. When bleeding the brakes, does the m/c cover need to be on??
2. If so, how do you keep air from being sucked in?? the lid on the master is kinda like holding your mouth right to start a tough to get to nut ;) . i have had problems bleeding brakes and put the lid on and presto they bled out. when in reality there was just a bunch of air in the lines and i bled and bled and bled the the last bleed decided to put the lid on and they bled out. however it does keep fluid from squirting out when you pump the brakes between bleeding.
you keep the air from getting sucked in by checking the fluid level repeatedly.

the possiblity of brakes getting better is an air bubble might have burped its way up through the master. tommy