Thanks for the reminder
Yanmar lists an 80 Amp alternator that is a direct swap for your 55 Amp. Bearing loads do go up as you try to get more out of a V belt. The answer for realy high power is to add belts. The load gets more overhung but the required tension is reduced. The alternator and water pump bearings would be the first to go. Crankshaft bearings are tough. You probably won't have to increase tension enough that any of the bearings would fail prematurely with the 80 Amp.
