Engine won't shut down

[Overlander]

I recently changed fuel filters on my 300 Cummins, and in the process got air in the fuel lines. I guess I left the ignition on too long while I was bleeding the air out, because after getting it started and running it for a while, when I went to shut it down nothing happened. After turning the key on and off several times I finally gave up and went back to the injector pump and manually shut it down. When I went back up front I noticed that some of the dash lights were still on even though the key was in the off position. I assumed I had fried the ignition switch , so I ordered a new OEM one from the manufacturer(Monaco).
Got the new switch and installed it and it still did the same thing ! I'm at a loss as to what to try next
If anybody has any ideas I'd sure like to hear from you!!

[Overlander]

I recently changed fuel filters on my 300 Cummins, and in the process got air in the fuel lines. I guess I left the ignition on too long while I was bleeding the air out, because after getting it started and running it for a while, when I went to shut it down nothing happened. After turning the key on and off several times I finally gave up and went back to the injector pump and manually shut it down. When I went back up front I noticed that some of the dash lights were still on even though the key was in the off position. I assumed I had fried the ignition switch , so I ordered a new OEM one from the manufacturer(Monaco).
Got the new switch and installed it and it still did the same thing ! I'm at a loss as to what to try next
If anybody has any ideas I'd sure like to hear from you!!

[charliez]

Sounds like a fuel shutoff selinoid (sp?). I read about this on other Cummns forums about trucks.

[Dougmyers]

Or an ignition power relay stuck.

Time to break out the wiring manuals.

[RustyJC]

It sounds like you may have a "run" relay that's energized by the ignition switch in the ignition "on" position. If the contacts on this relay weld themselves together, the Cummins' shutdown solenoid wouldn't de-energize and any other circuits tied to this relay would remain energized as well.

Rusty