The generator probably can be repaired. It may only need brushes, but rebuilding is a better choice. Before you take anything apart, connect a wire from the generator Field terminal to a good ground and run the engine. If the voltage comes up and the ammeter shows a charge, the trouble is with the voltage regulator or wiring, but likely the regulator. That also may be adjustable to correct the trouble. No increase in voltage with the field grounded indicates the generator needs repair. If the generator was working in the recent past, it may only need brushes- a pretty easy repair.
Harvester
