924Board.org

sneed21 · Guest

I need some help/advice. My 924 has new brakes, no air in the lines, etc...but my brake pedal pushes to the floor after about 2 or 3 stops. I have brakes, but it feels like there is no pressure behind the pedal. Does anyone know of any problems w/ the brake vacuum assist not recharging fast enough to hold pedal pressure? Is there anything I can do to fix this? Any/all advice would be appreciated.

Thanks

Zuffen · Posted: Tue Dec 11, 2001 5:28 am Post subject:

check the master outside and inside the car and see if it is leaking. The master shouldn't go to the floor even when the engine is off.

I think you have a bad master

_________________
Bob Dodd - 924turbo@cox.net
931 1982, 944 1982 euro, 924S 1988SE, 93 968 tip 06 Silver Cayenne S, 06 Black Cayenne S

I have Way too many cars, parts for the 931,944 and 951

sneed21 · Guest

OK, I've checked it...with the car off it does not push to the floor (ie..you have pressure). If you turn the car on and back out of the garage, it's fine..it's even fine when I put it in 1st and pull to the stop sign. Once I start out and press it again (for about the 3rd time) it goes almost to the floor...like all the pressure is gone/bled out.. Anybody out there have a spare Master Cylinder for an '80 924?

Zuffen · Posted: Tue Dec 11, 2001 7:25 am Post subject:

Wait a minute. Hmmmm you need to to check the one way valve going to the line going to the booster. Also check the booster by bringing it under vacuum .

Under power the booster may be sucking down the master cylinder.

_________________
Bob Dodd - 924turbo@cox.net
931 1982, 944 1982 euro, 924S 1988SE, 93 968 tip 06 Silver Cayenne S, 06 Black Cayenne S

I have Way too many cars, parts for the 931,944 and 951

kaffine krazed · Guest

How old is the brake fluid? Brake fluid asorbs moisture over time wich lowers the boiling point. So your brake pedal would be fine when the brakes are cold but when they get hot the fluid boils causing the brake pedal to sink.

A bad booster would cause a high hard pedal so would a vacuum supply problem to it.

numbers · Guest

Even though you indicate that the brakes are fully bled, your symtoms are typical of air in the lines.

sneed21 · Guest

You both sound right.....I'm going to try new brake fluid/bleeding them again. Thanks for the advice.

a.