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MikeMerru · 11-04-2018, 04:08 PM

I have a Onan 7000 generator model7HGJAB-900 in my 2003 Coachman class A that will not run since I ran out of gas. I have since then replaced the fuel filters and fuel pump without it helping. The motor turns over and starts quickly then dies just as fast. Thank you in advance for your help. Mike Merry

paddler1954 · 11-04-2018, 04:40 PM

If you ran your fuel tank below 25%, then you probably have air in the line to the generator. Press the switch on the generator that you use to start it, except press the STOP side. Hold the switch down for 20 seconds or so. This action primes the generator. Release the switch, then press the Start and hold until the generator starts. If it still doesn't run, try priming the generator again. Hope this helps.

twinboat · 11-04-2018, 05:43 PM

Check the oil, just in case its low, by coincidence.

GREGORYJ · 11-04-2018, 08:16 PM

Another possible cause if the generator stops after starting and when the start button is released is that it is not generating AC power. If it stopped suddenly under load, the brushes may be stuck from heat. It's an easy thing to check, remove the one 10mm bolt holding the brush holder in place and pull them out. The 2 spring loaded carbon brushes should slide easily in the holder, if one or both are stuck, that will cause the generator to stop. If stuck, sometimes pushing on the brush can free it, if not, replace them. See example of a stuck brush and damaged holder.

MikeMerru · 11-13-2018, 04:16 PM

Quote:

Originally Posted by GREGORYJ

Another possible cause if the generator stops after starting and when the start button is released is that it is not generating AC power. If it stopped suddenly under load, the brushes may be stuck from heat. It's an easy thing to check, remove the one 10mm bolt holding the brush holder in place and pull them out. The 2 spring loaded carbon brushes should slide easily in the holder, if one or both are stuck, that will cause the generator to stop. If stuck, sometimes pushing on the brush can free it, if not, replace them. See example of a stuck brush and damaged holder.

Where are brushes located

GREGORYJ · 11-13-2018, 10:49 PM

I found a couple of poor quality pictures on line to show the brush location which is
above and behind the generator breakers/start button block. The brush block is held in place by one 10 mm bolt and slides out of the top of the generator assembly. It has 2 wires connected to it. The air filter can be left on if you use a ratchet, long extension and 10 mm socket. The brush holder can be pulled out enough for you check that each brush is not stuck and slides easily in the holder.
If not stuck(or worn out), re-install as this isn't the problem.

If, after the generator stops, the red light in the start button is flashing, then the generator control board has recorded problem codes that can be determined by counting the flashes and checking what they mean in the trouble code chart in service manual. Goggle and you should find the service manual to down load for your generator model. Good luck Mike.