A friend of mine added power front disc brakes to his 66 coup. He says the pedal feels good when bleeding but, feels "soft" after starting the car. He said; it stops but the pedal goes to the floor. There are no leaks and dosen't seem to be any vaccum leaks. Is this normal? should he have replaced the proportioning valve. Any suggestions on what to look for?

 

Under no safe condition should the pedal ever make it to the floor. If you bled all the line then there could be an air leak in one o the break lines. The rubber section on the brake lines could be very old and expanding under pressure and or leaking they should be replaced as well.
Vacuum leaks and proportioning valve have nothing to do with the peddle going to the floor.

Gun

 

He MUST bench bleed the master cylinder or there will be air trapped in there which is what it sounds like.

 

Did he change the master cylinder along with installing the brakes?

 

Yes, also changed the master cylinder and bench bled it. Would you be able to see the expansion of the rubber brake lines? Would there be a differenc ebetween bench bleeding it in the car with a bleeder kit and bench bleeding on the actual bench? I don't know which way he did it but, though I would ask and then see which way he did it.

 

When the calipers were installed, which way are the bleeder facing? Up or down?

 

Not sure, I will ask. Is there a right and wrong way?

 

Yes, the bleeder valve MUST be facing up or you will never get all the air out.

 

OK, more info. Bleeder valves are facing up. New stainless steel front brake hoses were installed. He bled the master in the car with a kit.

 

That's you're problem!! Most times bleeding it in the car will not work.. You can't get the piston all the way to the end of the stroke. I don't care what kit you get, the best way is a bench bleed... Tell him to pull it out, put it in a vise and bleed it that way and you will use a screw driver or shaft to get the piston all the way to the end of the stroke.