Uh, that was a pretty short description. If I read this right and am reading between the lines correctly, it sounds like gas got added to your oil reservoir. I presume someone gassed up your boat and put it in the wrong place?
With that assumption, it sounds like you ran the engine in a very oil starved state. This would reduction the lubricating efficiency of the engine and possibly cause it to run hotter.
Remove the grey plastic cover behind the engine (where you should also see a grease fitting). Remove the spark plugs and check color. See if you can rotate the engine by hand at the shaft behind the engine.
