Just an update, i aint cussing my 15hp merc. anymore. Love that sea-foam. Also found a spray form called deep-creep, made by sea foam. Its great stuff, eats varnish up. I had some leaks on my boat and wasnt sure how to fix them the right way. Its a 1975 eldocraft riveted boat. I found a thread on here talking about epoxies from Fasco. I ordered a gallon and put two layers on it from the rub rail downand from bow to transom. I must say that is bad stuff! Not only does it seal all leaks but it also improves the performance running across the water. I was thinking about selling it and buying an alweld but like I said Im kinda partial to that old boat so I think ill keep it for while longer now. thanks to all for the excelent info.