These days, most OEM engines are left unpainted, just the raw aluminum left to oxidize and get covered in that white powder.
WD-40 is known as a cure-all for lots of problems around the home, but these special WD-40 formulas are more effective for ...
Get rid of them before they set.
Deep cleaning an off-road 4x4 Jeep, including underside and engine bay cleaning, and how to wash a very dirty car.