1984 Johnson 15ECRM (manual, electric start) Motor sat for approx 4 years. Rebuilt waterpump, carb, fuel pump and redid some wiring. Motor ran several dozen times on hose and in barrel. Good water stream before and after new impellor. Night before sea trial noticed red wire from rectifior corroded and broken off. Had to strip back all the way to rectifior and splice in a new one. Took boat over to Riverbreeze ran for about 10 minutes on plane (20mph?) 15' Johnsen skiff w/ 2 adults. Motor started slowing down to about 10 mph and then down to about 5 mph and noticed smoke coming from cowling. Smoke dissapated and removed + cable before opening cowling. Motor would pull through manually but not start. Towed back and checked when I got back home and noticed several heat related problems. 1 wire from power pack to coil melted through heat shield and insulation and probably grounding out. Both coils show melting where the attach to block. All 3 coil mounting bolts loose ( all where tightened recently). Checked for spark with tester built using SSCHAPTERPSA website. Spark will only jump 1/4" inch not 1/2" described on that website. Shot premix straight into carb with no result. Don't have much experience with outboards but have researched many forums. What should I try next?