T/A Brake Issues `````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````````

[RANDY LOBERGER]

Finished my T/A a couple of years ago but have been struggling with brake issues and am at my wits end. Problem was soft pedal and brake light coming on when applying brakes. All new brake system components and rebuilt original power booster. In trying to resolve the problem I replaced master cylinder and proportioning valves with no improvement. Then took the car to local garage, they replaced front and rear wheel cylinders and adjusted brakes. Some improvement but by no means did it have sufficient pedal. This year I decided to try a new booster, (original one rebuilt by Dewey). After installation, the brake pedal feels normal, returns to neutral position when car is not running. When I start the car, the pedal goes to the floor and does not return. Any ideas, suggestions appreciated.

 

[benguin]

With all new wheel cylinders, master cylinder, and the shoes adjusted that rules out many of the culprits. My first thought was there is still some air in the system. I'm sure you've confirmed the spring for the power brake lever push rod is in place, right? Other than an air leak introducing some air (maybe the proportioning valve connections?) or low fluid, maybe comething more obscure- linkage interference?

 

[Chryco Psycho]

If the brake warning light is coming on there is an imbalance in pressure in the front & rear systems moving the metering valve off center & tripping the light , the only way I can see this happening is if there is air in the system or the master is not creating pressure correctly . Are the front calipers on the correct side with the bleeder at the top , Yes I have seen them installed upside down a number of times ?

 

[RANDY LOBERGER]

Linkage in place, the master cylinder spring seems to be working fine, it returns the pedal to normal position when the car is not running. It does seem to be stuck when I remove the unit after depressing the pedal with the car running and booster operating. Front calipers are on correctly, have seen them installed upside down before myself. Brake light is not coming on now with the new booster. Car actually has much better brakes with the new booster, but problem is pedal staying down and brakes remaining engaged. Linkage does not seem to be binding since pedal return is normal when the car is shut off.