I recently bought my first boat and it has a 1961 75hp evinrude starfliteIII engine on it.The boat has been stored outside for some time in the rain. Upon loosening the bottom oil plug about 1/4 cup of water came out followed by some oil that smelled of fuel. How bad is that and what will it take and cost to fix? Can i fix it myself? Any help would be greatly appriciated.