Engine: To paint or not to paint aluminum and bronze parts
I've just removed what seems like several pounds of paint from some engine parts which turned out to be cast aluminum (crank pulley, exhaust manifold, etc) or bronze. I'm tempted to leave them free of paint as they look very nice but it appears that the "normal" thing to do is to paint the entire engine the with the same paint. Would it be a mistake to leave these parts bare? I.e. would I be risking corrosion or other problems?