Re: rebuild it?
the first thing i would do is tilt the engine all the way up, and put marvel mystery oil in each cylinder, and let it sit atleast over night. thrying to turn it over with out doing this can break a ring. then lower the engine and clean up the oil, turn the engine over ny hand so the rest of the oil comes out. after 15 years theres no lubircation in there. then if it will turn it over with the starter up the plugs out, and be ready for a spray of oil. now do your compression, and spark test. you never know it might be alright. do the steps in Awakening a Sleeping Outboard, found in the engine faq forum. good luck, keep us posted. just because it sat doesn't mean it needs a rebuild.