Onan Gen Power missing at one leg

[PrestonH22]

I am trying to troubleshoot my gen and looking for some knowledge. Any ideas would be appreciated.

Generator has 2 breakers on the control panel. There are 2 black wires coming from deeper inside the generator into the control panel each feeding their respective breaker. Measuring directly on the wire terminal at the breaker, one wire has 120 VAC and the other has 0. I am trying to find the cause of the dead leg and how to fix this.

I took a few measurements based off other suggestions, not sure what they mean. supposedly all within spec.

1. Pins 1 and 10 (Rotor, sliprings, brushes), 88 ohms cold after 2 months, ~33 ohms AVG after cranking and taking multiple measurements

2. Pins 3 and 9 (aux stator windings), 2.7 ohms

3. Pins 4 and 5 (windings) , 0.4 ohms

Onan 5500 Marquis Gold out of a 2004 5th Wheel
Model #: 5.5HGJAB-1038C
S/N: K030564396

[d23haynes57]

You need to determine how your generator was wired at installation. There is usually a choice for split leg 240-120 volts with neutral or for both to be 120V and the Neutral. Basically, the windings are in series with a center, or they are paralleled. For the later both breakers will be 120 to the neutral or ground and 0 to each other. There should be a connection box or terminals to set that up. Either a wire is open there or the generator lost a winding on the stator.

[DarkSideJeep]

Originally Posted by PrestonH22

I am trying to troubleshoot my gen and looking for some knowledge. Any ideas would be appreciated.

Generator has 2 breakers on the control panel. There are 2 black wires coming from deeper inside the generator into the control panel each feeding their respective breaker. Measuring directly on the wire terminal at the breaker, one wire has 120 VAC and the other has 0. I am trying to find the cause of the dead leg and how to fix this.

I took a few measurements based off other suggestions, not sure what they mean. supposedly all within spec.

1. Pins 1 and 10 (Rotor, sliprings, brushes), 88 ohms cold after 2 months, ~33 ohms AVG after cranking and taking multiple measurements

2. Pins 3 and 9 (aux stator windings), 2.7 ohms

3. Pins 4 and 5 (windings) , 0.4 ohms

Onan 5500 Marquis Gold out of a 2004 5th Wheel
Model #: 5.5HGJAB-1038C
S/N: K030564396

The generator has two brakers as well. Have you checked the generator breakers? I have been there myself.