Corroded Brake Booster

[nghtshd88]

I noticed that my brake booster is corroded on the front from what looks like brake fluid leaking on it for years. Are there O rings that can be replaced between the cyclinder and booster? Or do you have to get a new booster period.

 

[joegr]

Brake fluid leaks from the master cylinder, not the vacuum booster. If you have a leak there, then you need to replace the master cylinder.

Unfortunately, fluid leaking from the master cylinder tends to get sucked into the vacuum booster. It degrades the diaphragm and the valves and seals inside. If you really have brake fluid leaking from the master cylinder, the best thing to do is to replace both the master cylinder and the brake booster.

BTW, brake fluid will not corrode the metal of the vacuum booster. However, it will remove the paint from the metal, and that will allow moisture to get to it and corrode it.

 

[LS4me]

EVERY Ford product I have owned since 1986 has leaked from the cap on the master. It seems to seal correctly and isn't loose, but fluid has always leaked. Doesn't matter what I do to try and stop it.

 

[joegr]

EVERY Ford product I have owned since 1986 has leaked from the cap on the master. It seems to seal correctly and isn't loose, but fluid has always leaked. Doesn't matter what I do to try and stop it.

Yes, if that's what he is talking about, the reservoir will always be a little damp with seepage from the cap vent.

 

[LS4me]

Yes, if that's what he is talking about, the reservoir will always be a little damp with seepage from the cap vent.

It's a vent? It's supposed to leak? Well, that sucks! I'm constantly trying to keep that clean....

 

[joegr]

It's a vent? It's supposed to leak? Well, that sucks! I'm constantly trying to keep that clean....

No, it's not really supposed to do that, but it does. The rubber bellows in the cap is supposed pull in towards the reservoir as fluid leaves it for the calipers, and then it's supposed to come back up as fluid returns. Instead, it stays put and the cap vents where the rubber meets the plastic reservoir.

In the old days of big metal reservoirs, the caps and bellows actually worked correctly and the outside stayed dry. The plastic ones always seem to seep.

 

[nghtshd88]

I know its leaking from the cyclinder and no not the cap at all. It corroded the paint but my brakes do suck. They are new too. Its a lil mushy but if i stand on them they dont really stop. I know they have to be bled but to understand right the booster can make the brakes suck not so likely the cyclinder if it just has a small leak?

 

[rsimmons1]

I changed the drivers front upper control arm which requires you to remove the master cylinder and set aside... I didn't put it back in properly and it leaked into the brake booster... I had to replace the booster and master cylinder.

 

[nghtshd88]

Yea I saw that.. I need uppers too. Booster cyclinder, suspension, COP cooling.
I might just spend more to replace then i paid for the car
at 100k.