Watching some shows on TV I noticed these mechanics using Marvel Mystery Oil to free an old Packard engine. It worked. It was red in color, so it may be possible that MMO is really ATF and Acetone! BTW: How did MMO grade in this mad scientific test? Tried Kroil and no go for freeing up the Buick 225 V6. Next up, reverse electrolysis.
I have Wurth and Gibbs on hand, but usually use wax. Recently changed three of the original O2 sensors on my '97 Astro with 340,000+ km on it. Touched a candle to the base of the sensors while the system was still fairly hot, when it was cool enough to touch I cracked 'em loose and unscrewed 'em. Anything really rusty needs to be wire wheeled or sand blasted first, warm the part with some sort of torch, touch the candle, loosen. If there's paint nearby, a heat gun will get parts hot enough for the wax to wick into threads.
The Jalopy Journal
