Where did you find a 200 amp generator and what are you using to run it? It will not produce any more output current than what the electrical system needs unless you do a full-field load-test. At that point it would blow a 175 amp fuse. If you install a larger fuse, the wiring will be the weak link in the chain and will be overloaded.
If the dash gauge is bouncing around, the common causes are loose or corroded battery cable connections, loose ground wires, and one defective diode inside the generator. The load test would identify a bad diode. The maximum output that could be developed would be exactly one third of its rated value, and "ripple" would be very high.
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Tuesday, February 12th, 2013 AT 2:50 AM