I have a spec K Emerald Plus built in March '94: C943138824
It only has about 530 hours on it which I am told is not really a lot.
I cleaned out the carb, changed the plugs and filters when I got it and it started and ran like a brand new generator for about 40 hours over a 2 month period. It then started struggling with starting, then would start and run for a few minutes, then die... now it won't run at all. I have determined that it is getting no spark and though I am a mechanic, I don't know much about generators. I have decided that it needs to come out of the RV for testing so I am looking for advice on setting this up and where to start with testing. The manuals I have looked at are far from thorough and message boards are just frustrating. So.... If you were me... where would you begin? I have tools and a good multi-meter, test light etc. as well as big batteries for cranking on the bench etc.
Thanks in advance.

 

Welcome to the forums.

A good service manual is mandatory for servicing a unit like that. If you don't have one you can download and copy the one from the link below. I would suggest looking at it, in particularly, the diagnostic section and going from there.

If the unit is installed in a motorhome then it may have to come out. I've serviced some in motorhomes but most need to be removed for servicing.

You can feel free to post any questions and we'll help you out.

Cummins-onan-manuals.pdf

 

I bought a used Yamaha generator and it ran well one season. The following season I went to start it and it wouldn't start. I pulled the plug and determined that it wasn't getting spark. After some investigating online I was lucky enough to get some interesting advice. I was told that with the new ignition systems, you may be getting spark but not seeing it. Lo and behold, that advice was right on. Try checking for spark with the lights out. You may be getting spark but not seeing it.