I have a 1988 40Hp Johnson Outboard Electric start,tiller steering. This weekend I had a problem with it dying as soon as I shifted it into forward gear. It ran ok out from the boat ramp. I stopped and put it in neutral when I shifted it back into forward it died immediately. It started right up, shifted and it died again. I backtrolled for awhile then tried it in forward and it ran about 200 yds and quit. Backtrolled again for 10 minutes tried it again and it ran fine. Never had this problem before. Is there a kill switch in there somewhere that was shutting it down. Any ideas?