I have a Generac NP-66G M/N 09600-2 S/N 1527432 in my 1996 Gulf Stream motorhome. The motor starts and runs fine but I am getting only 2.4VAC measured at the circuit breakers on the generator. The generator was working fine in March but suddenly quit. It's demise seemed to correspond with taking a good jar when I ran over a curb. Before I throw any money at this I'd appreciate it if someone would read what I have been able to determine and give me advise on what the likely problem is.
I have checked all the wiring for broken or bared wires and everything looks good. I noticed the LED on the voltage regulator comes on when I press the starter button but doesn't stay on.
I have worked my way through the troubleshooting flow charts in the
Diagnostic Repair Manualand am getting inconclusive results (at least to me). This is what I am getting:
1. I have no way of checking frequency but the voltage is low (residual?) so I did the Fixed Excitation Test. The expected result is 45%-55% of rated voltage. I measured 101.8VAC which is more like 85%.
2. I then checked the excitation circuit breaker which is normally closed. I found no continuity so I ordered a new one. I put in the new one and it still didn't work. When I checked the new one it no longer had continuity so I assume there is a short or something is causing it to overheat.
3. I then tested the stator winding. I measured 1.5ohms which is very close to the expected 1.6 ohms +/- 0.08. I tested for a short to ground and found no continuity. I checked between stator lead #2 & #11 and found no continuity. I then checked between #2 & #33 and measured 5.4ohms when there should be no continuity. So I think this indicates a problem with the stator.
4. After reading posts on low residual voltage not providing enough to flash the field I did the Field Boost checks and in all three checks I measured 12.45V when 9-10 V is expected. I tried flashing the field with a battery and with an electric drill but nothing improved.
5. While I was checking for bare or broken wires I looked at the brushes and they look good.
Your input would be appreciated. Are there other checks I should be doing?
Tim
