Brake booster interchange

[hanko mechanico]

Will a 1959 Bendix treadle vac booster work properly in a 1957 Lincoln capri ? Seems to mount correctly with a bit of pedal free play has plenty of vacuum but doesn't have boost

[Dan Szwarc]

How can it have vacuum but no boost? Figure out how to shim out the play.

Make sure the booster is sealed to the master cylinder.

[hanko mechanico]

It has vacuum to the booster but won"t assist with braking no matter where I adjust push rod . I disassembled the booster and inspected the leather seal and all the rubbers parts and valves and everything appears ok. That"s when I realized by parts identification the booster is out of a 59 60 lincoln or ford. There has to be something not working properly. Just not an expert on brake boosters but use a little advise that doesn"t include buying a new booster. Another thing is that sometimes the master cylinder doesn"t completely return and holds some pressure on the brakes. Can"t seem to see an issue with the master cylinder either.

[frasern]

It sounds like plugged check valves on both accounts. the one in the booster can be removed fairly easily and checked. There is a ball valve in the tip of the master cylinder, right at the tube connection. On my '62 3 ton it got gummed up and caused the symptom you describe, I had to disassemble the cylinder, and clean and flush the valve, I don't think it could be removed. Flush it with solvent, forcing it through the valve, then do the same with methyl hydrate, to remove the solvent.