a little more info on your engine would be helpfull. kohler did both 2 and 4 strokes. a good lawn mower battery should be enough to get it going... if everything else is ok. the smoke tells me that you have a lot of resistance somewhere. check and clean all the cables in the starting system. also try pulling out the spark plugs and see how it cranks. while they are out check spark and compression. it's probably got points, and if it has no spark they might need cleaned/ adjusted. also check to make sure fuel is getting to the carb. 16hp is enough to give you a good taste of what one of these can do, and you can always upgrade later. i'd try to get it going, before i went to the trouble of an engine swap
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