I have a 1990 bayliner with a 2.3l ford engine. It has a omc drive. We took it out one night and it ran perfect for about a half hour, we were at a low idle, put it in gear and it just stopped, tried to start it and it sounds like the battery is almost dead. Waited over night and tried it the next day, it started for a while then died again, same thing like the battery is dead. Does anybody have any ideas of what it could be, or what should I do next.