If you get it to spin over, first make sure no dirt in carbs...put a vacuum cleaner on each carb to suck out any dust or dirt. Next remove all spark plugs and check for rust. Next mix up a little gas and 2 stroke oil at about 24:1. Squirt some in each cylinder....about 10ml. Turn over a little bit to pre lube and juice up those dry cylinders. Set motor on floor, face up, and put same amount in each carb and spin a little bit. Making sure plug wires will not arc to something and cause a small fire. You have now done a preliminary lube and can perform your compression test. If you get some decent numbers....say between 115 and 130 psi, then do an arcing test on each plug wire....one at a time with spark plugs out and looking for a nice 7/16" or greater white/blue crackle....lightning like spark. Devise a simple gap tester using a little creativity. Simply said.....you could have a helper hold the handle of a #2 Phillips with the tip inside the plug boot and the shaft held approximately 1/2" from a metal object on the powerhead. Then.....if these things test out, you are onto a possible jewel of a motor. Check oil in lower unit.....if it is full or partially full, and clean, with no milky/cloudy appearance in color.....then the motor really has some hope. Before you intend to crank it over, make sure no wiring is cracked or shorting out. When it gets time to do a starting attempt, consult the forum for additional suggestions.....like a new water pump impeller.
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