Replacement alternator.
Herb, I just spotted one on eBay for $300.00 so maybe you can she around to find an even lower price. Years ago I took my Yanmar alternator to a local rebuild shop and remember the technician remarking that it was identical to a Mitsubishi alternator. I quizzed him over details that would make it a marinized version and he remarked that mine was identical to the automotive version. It's still running like a top all these years later. I recall that the cost was $90.00 for new diodes, bearings and a thorough clean up. Maybe you could have yours rebuilt too???? Glyn Judson, E31 hull #55, Marina del Rey CA