Brakes issue, "Help"
Thread Starter
Instructor
Joined: Jun 2008
Posts: 107
Likes: 0
From: arlington texas
Brakes issue, "Help"
I am in need of some help/advice with a soft pedal on my 81. Here is what I have done to date.
Removed the calipers for refinishing. Replaced the front units with new as the old units looked to be leaking.
Replaced the front hoses
Bench bled the master cylinder
New cap on MC.
Power bled with a motive bleeder. A lot of fluid. I have also gravity bled, a lot of flluid.
With motor off pedal pumps up pretty solid but if I leave it for few minutes pedal will lose some pressure.
Motor on no pedal.
No leaks that I can see, touch etc.
Could the proportion valve/switch be an issue. Brake light is always on.
I am at wits end. Can't drive it to garage. My garage sets on pretty steep driveway.
Hope someone can offer some advice. thanks in advance
Pepe Griffo
Removed the calipers for refinishing. Replaced the front units with new as the old units looked to be leaking.
Replaced the front hoses
Bench bled the master cylinder
New cap on MC.
Power bled with a motive bleeder. A lot of fluid. I have also gravity bled, a lot of flluid.
With motor off pedal pumps up pretty solid but if I leave it for few minutes pedal will lose some pressure.
Motor on no pedal.
No leaks that I can see, touch etc.
Could the proportion valve/switch be an issue. Brake light is always on.
I am at wits end. Can't drive it to garage. My garage sets on pretty steep driveway.
Hope someone can offer some advice. thanks in advance
Pepe Griffo
Last edited by pepegriffo; Oct 19, 2009 at 02:40 PM. Reason: spelling
Pro
Joined: Jul 2008
Posts: 699
Likes: 3
From: Millersville, MD
The brake light being on could very well be an indication of the proportioning valve stuck in one position. Someone will chime in with the method to get the light to go off cause I forgot. How long has it been since the MC has been replaced? I just replaced my rear calipers and lines and used the motive power bleeder to bleed my brakes. My problem turned out to be the MC. I had the same symptoms except for the brake light.
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
The light on is due to the switch being pushed to one side or the other. Crack a linr on either the front or back and push the pedal down, the light will go out when the switch resets. If it doesn't, close that line and crack one on the other end of the car and repeat. The fluid on the closed side will push the shuttle to the open side, go slow on the pedal.
Once thats done, rebleed the system, the motive pump works well, watch for bubbles coming up in the MC.
Once thats done, rebleed the system, the motive pump works well, watch for bubbles coming up in the MC.
