You say you turn the key on and get spark ? Now are you jumping the starter and cranking the eng with the key on to get spark or are you saying you get a (1 Spark) spark when the key is turned on ? I ask because I have seen some throw a constant continuous spark with the key on and not cranking and also just get one spark when key turned on and then off? So I want to know if you are cranking the eng by jumping the starter and/or starter relay to crank the eng with key on and see spark ? Ron