PDA

View Full Version : pwer brake booster



forrest
06-19-2010, 05:02 PM
I have a 55 speedster that has factory power brakes that just don't do the job well. I've had them overhauld and all the good stuff but little help. I have seen the newer modern type on cars at show and would like to do the same. what size, brand and part no would anyone like to suggest? I know I'll have to figure out a swing pedel system but I think the nwer type would be worth the effort.

N8N
06-19-2010, 05:05 PM
Something's not right, I've found the old Hydrovac systems to be if anything overboosted for my taste. When they're working right, they work very well (if by "very well" you mean that you have that feather-touch brake pedal that was popular on older American cars.)

nate

58PackardWagon
06-19-2010, 10:17 PM
Forrest I just spent half the day working on mine today and it does an absolutely outstanding job stopping the car. You might want to have yours looked at to see if it is functioning properly.

stall
06-20-2010, 02:40 PM
I finally read the manual and while repainting the battery box i added the correct amount of "Neatsfoot" oil . Its not east with the port at the bottom of the booster so I fashioned a stand pipe using a 90 degree fitting and a pipe with cap.

In any event I found it made a very dramatic difference and completly eliminated mu grabbing brakes problem. I don't know if it makes a difference but I'm running silicon brake fluid.

Good Luck, Murray

bezhawk
06-20-2010, 03:05 PM
The Vaccum piston inside the booster is kind of like a big accelerator pump in that it is leather sandwiched between two steel plates. There is a rope wick also 'pinched' between them so that the neatsfoot or any light oil will wick up around and keep the leather from drying out. If your booster hasn't been serviced regularly the leather will shrink and not hold vaccum . No vaccum= no boost. Also the control diaphragm might be bad or leaking. they are usually very corroded in the controll valve/ diaphragm area. I rebuild my own, but you can send them off to booster dewey(sp).
There is a leather lip seal on the main body that the push rod from the vaccum piston goes through. This has to be installed correctly or you will mysteriously loose brake fluid. (lip towards slave cylinder).