Black over black and the rust comes back
Often the question comes up should I strip the primer off replacement panels. This primer is usually black. It's a difficult question. If the metal had any type of rust and it was primed over at the factory usually in Taiwan it will bite you later.This is a picture of floor pan that was painted over with black moisture cured urethane over the black factory primer about five years ago.The AC drain leaked under the carpet and caused it to rust beneath it.How did that happen , that rust would form under the coatings? The answer ,black is not airtight, the silver should have been used first, then the black.Has anyone else experienced this problem?