[rumrumm]

I have a problem with my power brakes and I am at my wits end trying to figure it out so I could use some help diagnosing it. The car is my '32 which has a Corvette dual master cylinder and a singe power brake booster. When the car is shut off, the pedal seems fine--springs back like it should. As soon as I start the car and push on the brake pedal, the brakes grab but they will not release (both front and rear) when I let up on the pedal. I have replaced the booster thinking the diaphragm inside was bad, played with the length of the rod connecting the pedal to the booster. I checked the rod and it is perpendicular to the booster. The Wilwood residual valves are installed correctly. So far, nothing has helped. The vacuum hose is connected to manifold vacuum off the back of the Edelbrock carb. What could be wrong here?

[yesgo]

Is the pedal itself actually staying down? Can you pull it back up to release the brakes?

When the brakes get stuck, will they release if you shut it off and pump the pedal?

How about if you unbolt the master from the booster while they're stuck... do they release?

[rumrumm]

Q: Is the pedal itself actually staying down? Can you pull it back up to release the brakes?

A: The pedal stays down. Pulling up the pedal and releasing it causes it to flop back down again.

Q: When the brakes get stuck, will they release if you shut it off and pump the pedal?

A: If I shut the car off, the brakes will release, although it is not immediate. The pedal works normally when the car is shut off.

Q: How about if you unbolt the master from the booster while they're stuck... do they release?

A: I have not tried that.

[johnsongrass1]

Bad master or the pedel or overcentering. Maybe both if the pedel travel is limited by the master movement.