There are spray paints from Tempo which are designed for outboards. They seem to last well and be compatable with the paint on the motors. if it is down to bare metal, or you want to completely strip the motor, then you will want to use a primer. For the pits, they need to be wire brushed out clean, cleaned with laquor thinner, then sanded with wet and dry to give a good tooth. Then JB weld works as a great filler. After the J B weld, then sand again. Get it smooth wiht up to 1000 grit paper, use wet and dry to keep from clogging. The surface prep is important. Then use strontium chromate primer (Zinc Chromate or zinc phospate have been also used), but I prefer epoxy Strontium Chromate Primaer. Alodine might be a good surface prep, but with the primer alone I have had excellent results. After the primer, a very light sanding, and apply at least 4 color coats. If the color coats are metalic, then clear coat with at least 2 coats. I have had this technique last years in salt water.
