Michiganfan19k

I bought a 2000 centurion ecplise last year and used to boat pretty often for a few weeks with no issues. I then had the boat in the water and had the belt lock up on me. After starting and shutting the boat off a few times, the belt was moving freely. I thought the alternator was starting to go so I replaced it with a new one. Boat ran fine for a few more months then it happened again! Haven’t done anything with it since. I did the same thing to free the belt up again but does this lead me to think it was possibly the water pump starting to go? Or am I missing something. Any help is appreciated as the boating season is coming in a few months!

Yea problem is the water pump is really the only other one I believe I can turn by hand and also does not help that it seems to big a devoloping problem that can go many many starts before the issue occurs