UPDATE - onan 5500 diesel generator will not stay running

Update on my friends generator.

She just got a call from the Cummins shop. Unfortunately not a simple fix.

The brushes were toasted, causing major damage to the stator and rotor. Total repair cost $4500 CAN funds. They said it may have been a servicing issue. Brushes need to be check/replaced when oil is changed. They also said the hour meter was disconnected, maybe by the previous owner so the 127 hours was not correct. She has never noticed that is was not moving.

Thanks for the suggestions. I will follow up once I hear back from her.

Cliky to the link from darsben. Great resource.

Here is a troubleshooting guide. The next step should be checking the low oil pressure switch to make sure it is functioning.

Q
. Why does my generator start and then shut down as soon as the start switch is released?
A
. Most models require both oil pressure and AC voltage from the generator to keep running. A lack of AC voltage can be caused by a variety of problems involving the control board, regulator, generator and wiring. A stuck oil pressure switch can also cause this symptom. The interaction between the various components of the system can be confusing during troubleshooting. Use the Troubleshooting Guide to isolate the problem

Guide is at http://www.flightsystems.com/pdf/onan-rv-troubleshooing-guide.pdf

Could it be the "On/Off" switch? If you press the switch one way to start, and then let go to run, and the other way to stop, it could be the switch is saying "turn off" when you let go of the switch.

Either check continuity of the switch with a meter, or try taking your finger off of the start/stop switch VERY slowly.

Thanks Big Katuna.
I have given her the link to this thread so she can follow it.
I also suggested checking the air filter.
I've read prior posts on this subject but could not see any solutions.

The next easy thing to try is replacing the fuel filter. Some manufacturers add an inline filter in front of the genset and most techs dont replace it as they often don't know its there. Tiffin for one did this.

Sorry. Forgot to mention that she checked the oil. It was fine.
Oddly enough it start immediately, sound good, just will not stay running on release of the start button.
Thanks

Check oil level first some have low oil cut off.