I am cleaning my winches and a couple of them were quite hard to take apart (yeah, it's been about 4 years, I shouldn't have waited so long). It was hard to get the tight-tolerance pawl gear assembly off the shaft of the ratchet gear spindle. They're not corroded, it's more like a thin film of gum or tar. Even after cleaning they don't spin as freely as they should. I'm afraid if I scrape it off I'll scratch things. Is there a powerful solvent for this, or would wed/dry sandpaper be the best, or something else?

Thanks,
Max