I have a 1991 yamaha 200hp that is not charging the batteries.I was wondering how to check the regulator/rectifier, it has three green wires that go to plug,one red goes to plug, and black.I have a multi test volt meter that I checked battery with, it was fully charged and at 2000 rpms I was getting around 13 I was told it should be around 14.I have been charging and swapping batteries every trip.Also how can I check the stator?Do I need a different meter to do this?Any help would be great.THANKS