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techdad55 · 07-16-2021, 07:44 PM

I have a QO 7000 (7HBJAB) generator. We were boondocking in 93 deg heat last night so we ran the generator all night. Once we got on the road I hit the stop on the dashboard to shutdown the generator and the light went out. I few hours later I stopped for fuel and the generator was still running. I tried to stop it from both the dash and the generator with not success. I resorted to pulling the air filter and cutting off the air intake to stop the motor. Something still has an open circuit. The fuel pump continued to run with the generator stopped. I had to disconnect the fuel pump wire to stop it. I looked for a fuse or circuit breaker for the generator but have not found one yet. Yes, I've been searching the forum and the new but everyone elses generator issues seem to be keeping it running, not shutting it down.

Any thoughts and help will be appreciated.

TIA
Steve

nvs4602 · 07-16-2021, 07:56 PM

My generators basically shorts the spark to ground. So I doubt it's a fuse, but is more likely a ground wire issue.

twinboat · 07-16-2021, 08:01 PM

Quote:

Originally Posted by nvs4602

My generators basically shorts the spark to ground. So I doubt it's a fuse, but is more likely a ground wire issue.

Shorting the spark doesn't stop a fuel pump, there more to it.

twinboat · 07-16-2021, 08:03 PM

There may be a relay that's stuck, keeping the power to the ignition and fuel pump.

You should be able to download the manual for that generator.

techdad55 · 07-16-2021, 08:50 PM

Quote:

Originally Posted by twinboat

There may be a relay that's stuck, keeping the power to the ignition and fuel pump.

You should be able to download the manual for that generator.

Good idea. I looked through my operator and install manuals and could not find any reference to a relay in the diagrams

powerpro · 07-17-2021, 08:41 AM

I had a similar problem with my older Onan/Cummins 3 cylinder diesel DKD generator a month ago. The fuel solenoid had a melt down in the "ON" position and the generator would not shut off until I disconnected the linkage to the fuel valve from the solenoid. In the process it shorted something out and now the generator won't start. After replacing the fuel solenoid, it will open the fuel valve and run the fuel pump but not crank the starting motor. I replaced the "Engine Monitor" printed circuit board (has 3 onboard relays on it) to no avail. I even have the wiring diagram and schematics but can't pin down the problem. I will find it eventually, has to be something simple.
To stop the diesel generator you have to shut off the fuel supply. My generator has a control box on it with circuit breakers for the AC output and two control switches for the dash and local control, as well as a fault reset switch. There should be some fuses or disconnects somewhere but I haven't found them yet. Your generator must have an automatic transfer switch somewhere that won't allow AC input and generator AC input to your coach simultaneously. You may have to have the experts that work on these things help you on this one. Hope you get it fixed, we really need our power plants!
Good Luck.

techdad55 · 07-18-2021, 09:55 AM

So I intended to disconnect the 12V this morning to see if it would 'reboot' the circuit board, or to leave disconnected. Before I dismantled anything I reconnected the fuel pump and amazingly the pump is now off. I shouldn't need the generator this week and we'll be in a new location for 2 months after that so I'll wait till we relocate to play with it again. I'll also be close to repair help after I relocate as well.
Thanks for the information.

connlonn · 07-18-2021, 12:52 PM

If your panel is like mine (QD7500) there are 3 fuses under the start/stop switch. 25, 20 & 15 amp fuses. I have to pull the 20 Amp while in storage so I don't get a random start. (No I don't have Auto start).
Good luck,
Lonnie