Cleaning Inside Brake Booster?

[PaulTWinterton]

I’m replacing my brake MC, so I decided to remove and clean the brake booster as well. Thanks to the FAQ threads on this subject I was able to remove it with very little problem. Bitch clip was surprisingly easy to remove. I rigged snare wire through the top of the clip for pulling it out. Hopefully the same going back in.

When I removed the MC I noticed brownish fluid in the booster. I removed most of it, about half an ounce. I’m pretty sure it’s brake fluid, but the color throws me off. Otherwise the inside of the booster is clean metal throughout.

How do I clean the inside of the booster? Varsol? Methyl Hydrate? Or leave it alone?

Pictures show the fluid and the MC connection.

Obvious brake fluid leak from the rear seal?

Thanks for reading and replying.

[c.d.iesel]

paper towel

Brake Clean spray

paper towel

dry

clean

don't forget the special square rubber o-ring

when installing the new master

[PatrickMTL]

As stated in the title, avoid it like the plague. It DESTROYS plastic, including the kind used to make relays and fuseboxes(ask me how I know), has a terribly noxious odour that lingers forever, and doesn't seem to clean all that well. I actually find it leaves an oily residue behind(?). Find yourself some Wurth brake and electrical cleaner, it works great, seems to be safe on most surfaces (including the relays and fusebox found in our '02's), evaporates at a reasonable rate, and doesn't stink up the garage for hours. My $0.02

[M3M3M3]

paper towel

Brake Clean spray

paper towel

dry

clean

don't forget the special square rubber o-ring

when installing the new master

+1

fluid looks like dirty/rusty brake fluid.

perfect time to give the outside of that booster a wire brushing and quick coat of black paint to purdy it up.

[jimk]

The MC has two seals on the rod. The inner seal seals the fluid in the MC the second seal is supposed to keep fluid from entering the booster and seals in the opposite direction to keep air from leaking into the booster along the rod.

In between the two seals on the MC bottom is a leak off hole. Make sure it is open. If in the future you see or feel brake fluid on the MC's bottom, it's time to do some maintenance. The leak off fluid is what eats away the paint below and causes all that corrosion on the frame.

[jgerock]

I spy the straight "tube" vacuum fitting on your tii booster rather than the common swivel plastic fitting (subject of another recent thread).

On the other side of the booster, there is a "fork" which connects to the pedal linkage, then a rubber boot which protects the shaft that enters the booster. Inside a hollow recess, there are several parts including a felt-like "filter" that should be inspected and may require replacing. I am doing this to my tii booster now and waiting on parts from BLUNT. Will post pictures when available.

These parts are on the REALOEM/Penskeparts diagram(s).

[PaulTWinterton]

Ahhh, words of wisdom. Thanks.

How the hell do I get paper towel into the booster. I tried using towel to remove most of the fluid. Not enough room to move. Ended up syphoning with brake bleed tube.

I will use brake cleaner, and I'm painting after I'm done. Make it pretty again.

I'm not enthusiastic about removing the other end to inspect parts. I can justify (to myself) not doing it, as this car has had an easy life, with 90k miles, and darn clean. Except of course the leaking brake fluid. I know, I know. Maybe I'll do it next time to practise my booster removal skills. ;-)

It's the old, "where do I draw the line". I started with rebuilding my transmisssion, then my clutch master, moved on to peddle box, now brake MC and booster. So I think, "I could upgrade my starter while it's staring me in the face". STOP. It's time to put it all back together and go for a drive.

Cheers.

[nbcbird]

Before installing the MC I gave my booster a generous shot of silicone spray to help lube the diaphram and coat the inner surfaces.

[TobyB]

Brake fluid's water soluable.

I just wash 'em out with dishes soap and water, then

dry them carefully.

Seems to work, no danger to the diaphragm.

t