Looks like we don’t have a definitive answer to the paint question as yet. So here is my $0.02 worth … To the best of my knowledge the pre-war motors that were “silver” colored were painted with simple aluminum paint, this for corrosion protection if not so much for appearance. Some parts, like aluminum flywheel or fuel tanks were polished. Our “dull aluminum” paint is the correct color. If you have an original motor that is aluminum “color” and you question if it’s bare or painted, try wiping with lacquer thinner, if it’s paint you will know.
Joe B
