I had my boat in the lake yesterday, and I noticed a couple of areas of rust on the crossmembers of my Continental trailer. It looks like there some of the welds that have started to rust. I might need to add that my boat and trailer spent the first 3-4 years of its life in the salt. I looked pretty close at the topside of the trailer and the only rust I saw was on the 3 crossmembers, and about 4 inches either side of center. I plan on pulling the boat off the trailer so I can get to top and bottom of the trailer, grinding/sanding the rusted areas, prime and paint. Since its just cross members, I'm not planning on painting the whole trailer, just repaired areas.
Any thoughts on paints or coatings? Should I paint the whole trailer? Anything else I'm missing?