A friend of mine has offered me a great deal, I THINK. He has offered me an old 1975 7.5 hp game fisher for 25 dollars. It runs fine it all works and is a little bigger than my 1969 6 H.P. evinrude. The rude pushes my old 13 foot v bottom almost to plane but just cant get there. I have heard that an air cooled power plant will make about 75% of the power that it's water cooled cousin will make. Is there any truth in that statement? I am going to buy it if nothing more as a back up in case something ever happens to my 6 hp evinrude. 25 dollars is not a great sum of money. Just wondering if I might consider it as a primary instead of a backup? Are these motors even worth the metal they are made of? To be honest it looks like a lawn mower engine bolted to a lower unit. However....