MY boat motor kept over heating we took it to a guy that said he knew what he was doing. he thought he fixed it. My wifes brother took it out one day and it over heated and stopped running. i thought i locked up, but i can turn the fly wheel with my hand and it will catch sometimes and i have to play with it to make it turn. i can hear something inside the head scratching around as it turns. my question is do you think the motor is locked up or can it be fixed and what do you think is wrong with it? The motor is a 1998 115 johnson