'55 Power Brake Booster

[James Mundstock]

I would like some feedback on a possible problem with my '55 power brake booster. I have replaced the master cylinder 4 weeks ago. Last weekend the pedal went to the floor. I pulled the drums and checked the wheel cylinders and they were dry. My reservior for the master cylinder was empty so I know air got into the master cylinder. The question is where did all the fluid go. My thought is the power brake booster is leaking and the vacuum is drawing the fluid into the intake and burning it in the combustion chamber. The brakes were power bled when the new master cylinder was put on and I had great brakes and fillled to the brim. I drove about 150 miles. I'm thinking I did not see any smoke from burning brake fluid because it was over a long distance. Is this common with these boosters?

[Mike Josephic CLC #3877]

Jim:

I assume you have a Bendix Hydrovac as that was standard in '55 for power brakes.

If you found no leaks in the sytem, then the fluid is being sucked through the vacuum
line and being burned up.  If you haven't rebuilt you Hydrovac (or had it done) that's
what you need to do.  There are some parts (including some from leather) that will
go bad with time.  Mike

[James Mundstock]

Thanks, Mike. I took off the booster tonight and when I turned it over to dump the fluid out, it also came out the vacuum port. That was my suspicion all along but I wanted someone to confirm it. Billy at White Post Restirations said the same thing. Glad there are good Cadillac people out there to help.