wfontenot

1981 928, Auto, 46k miles

I hope someone can help me because I'm running out of things to fix on my braking system. Recently, I have replaced the Master cyclinder, vacuume check valve, and new pads all the way around. I then took the car to the local brake place and had them bleed the system. After all of these repairs the pedal still travels to the floor and I have to pump the brakes to get the car to stop. My Rear rotors are worn down below turning specs. Is this why the pedal goes to the floor? Will changing the rotors really help?

abbzer0

I think I read that you need to bleed through a fitting on the master cylinder as well... feel free to chime in..

borland

The master brake cylinder is difficult to prime while in the car but can be done with the master brake cylinder bleed screw. A normal install includes an out of car priming with brake fluid.

Unfortunately, you will need to subsequently bleed the brake calipers.

Lizard928

use a power bleeder and do a reverse bleed, but yes the problem is that there is still air in the system

the flyin' scotsman

There was a recent discussion on bleeding the m/c first before moving to the front left, front right, rear left and rear right calipers..........somewhat against norm but was published by Porsche themselves and submitted to the forum by one of the 928 gurus.

wfontenot

Thanks for the info...The master cyclinder I purchased does not have a bleeder screw. Should I purchase a power bleeder?

abbzer0

FYI - my local Autozone just started offering power bleeders 3 or 4 weeks ago as part of their "loaner tool" program.

borland

No bleeder screw? Just remove the MBC, prime it, then reinstall it. Easy.