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Cleaning "Rust Dust" from a Distributor

Any suggestions for the best way to do this? One person said use electronic contact cleaner, another said to spray WD40 in there. Have you actually tried it? Thanks.

Either one should work with some ‘elbow grease’. I prefer to replace them when they get that bad.

I thought new ones were very expensive. This one I am aiming to replace the o-ring/s and tap out a distributor cap screw piece that broke off. I didn’t know you could really scrub the parts. I just though if you sprayed the correct substance, that the crud would hopefully just drip out. Thanks.

What kind of car are we talking about? Make, model, year would be very helpful.

That ‘Rust Dust’ comes from somewhere, and is probably from the bushings, springs, or weights. I’ve had the mechanical advance weights rust in place, and prevent the mechanical advance from working at all. I’ve seen springs pop loose or break. Simply spraying them with something doesn’t fix that.

Also, if the o-ring is shot, chances are the shaft seals are bad. Leaks in the shaft seals will let oil in under the cap and lead to mis-fires.

That’s why I suggested a replacement.

Don’t use wd 40, a little emory paper is my choice, and clean the inside afterwards being careful not to leave any oily finger smudges.

89 honda accord lxi. lately has gotten moist from dist cap hanging open on one side cause cannot currently screw it down. i have been cruising the junkyards but have not come across a distributor. those always seem to be out before i get to them. it’s leaking oil from that area. it is old - 482K miles. i have not seen oil near the cap, just drizzling down that side of the block after did valve cover gasket. it never misfires, but sure does not like 91 octane i put in it at times when crossing country. i will have it off next week. any tips if you have done that before? Thanks.

thanks. if it is not supposed to be oily at all in there, sounds like electronic contact cleaner would be most helpful cause it degreases and evaporates. i have not seen the inside of it lately. it could be ugly when i get it off next week.

I would definitely at least change the cap and rotor since they’re cheap. Just gently wipe off the rust dust with a clean rag or paper towel. I personally wouldn’t add any gunk-- the contact cleaner shouldn’t be necessary because you just changed the cap and rotor and the WD40 shouldn’t be necessary because the cap should keep any moisture out. The only “product” I might consider would be to blow it out with compressed air (while wearing a mask!).

I agree with Busted that there is might be a distributor replacement in your future, but if that dust has had the better part of 20 years to accumulate, it might not be anything to urgently worry about. I would just clean it up, do the cap and rotor and then check it again in a couple thousand miles.