"Corrosion Never Sleeps" a wise man working on a Florida Power and Light generating plant once told me.
A good product to fight corrosion is Boeshield T-9...developed by Boeing and is a lubricant and corrosion preventive product that essentially seals the surface. Once you brush off the rust and re-paint, apply the Boeshield on a regular basis. It wicks very well and dries to a waxy finish.
Great for your painted engine as well!
Available at any marine store and no, I do not have any affiliation with the manufacture or distribution of this product.
