Hmmm, DC motor,,,,
Never been into one of these units,,,but, it's a DC motor. Can you pop the end cap off of the housing? You know, the part that keeps things from being seen. Sounds like the brushes have worn and the resultant dust is letting current go to ground. When that lost current and the load increase from a nearly raised sail combine to reach the trip-point of the breaker, well, it trips. First thing to check. Usually the only expense is a new set of brushes, if that. Good luck. And what's with Lewmar not supporting a product that's only 7 years old. Who the hell is in the White Ho,,, oops, sorry Phil.