I have a mid seventies 25 horse johnson on my bowfishing boat. Lately its been giving me troubles. When I go to first start it I can crank it all day, with and without choke, with and without some extra throttle and it will not start, I give it anywhere from 15-20 minutes and I barely touch the key and it starts, and then it will run good for the rest of the day. Any idea what the problem could be? Sounds electrical to me but what do I know