Onan 4000 doesn't STOP immediately

[atreis]

I have an Onan 4000 on my RV with about 35 hours on it. Just recently it has started doing the following:

Starts up easy. Runs fine. Generates power fine.

Hit the stop button, and power from the generator turns off, the red light on the start/stop button goes out, and the fuel pump power cuts out, but the engine keeps on running. Eventually - 2-3 minutes - it will stall out. The change is that it used to stop right away when hitting the stop button. It doesn't matter which stop button I hit - the one in the coach or the one on the generator. The behavior is the same.

So... Not really a bad thing in and of itself, given that it's probably draining the fuel from the carb before stalling, and definitely something I can live with, but I'm wondering if it's an indication of some other looming problem.

[Jimbo56]

No idea. But I hold mine down on stop for a 2 count. Don’t know why I do that, just do. I’ve got to prime mine for a count to 60 to start it.

[16ACE27]

It is supposed to stop instantly when the stop button is pressed - no need to hold it. The fact that yours is delayed may indicated a sticking relay in the generator controller. Probably needs to be checked by a Cummins shop.

[Pete'sMH]

For as much as Onan charges for their generators they really do have some serious weaknesses. Most of them are noisy, have unreliable old school carburetors and other issues. We recently downsized to a class B that came with the newly redesigned 2800i. It’s whisper quiet and starts instantly. Why can’t they make all of their generators like this??

[16ACE27]

Originally Posted by Pete'sMH

For as much as Onan charges for their generators they really do have some serious weaknesses. Most of them are noisy, have unreliable old school carburetors and other issues. We recently downsized to a class B that came with the newly redesigned 2800i. It’s whisper quiet and starts instantly. Why can’t they make all of their generators like this??

$$$$

[atreis]

Thanks all. An issue with the control module seems the most logical source of the issue, so I'll start there with investigating further.

[The Gritz Carlton]

Originally Posted by Pete'sMH

For as much as Onan charges for their generators they really do have some serious weaknesses. Most of them are noisy, have unreliable old school carburetors and other issues. We recently downsized to a class B that came with the newly redesigned 2800i. It’s whisper quiet and starts instantly. Why can’t they make all of their generators like this??

I need to have mine checked. It's very quiet which now has me concerned. They obviously forgot to install my carburetor, there's water getting into the radiator somehow and it doesn't use enough fuel...only 3/4 gallons per hour. I'm pissed!!!

[16ACE27]

Originally Posted by The Gritz Carlton

I need to have mine checked. It's very quiet which now has me concerned. They obviously forgot to install my carburetor, there's water getting into the radiator somehow and it doesn't use enough fuel...only 3/4 gallons per hour. I'm pissed!!!

Damn Gritz! I have the exact same issues with my Onan generator. Plus it starts every time I ask it to!

[atreis]

Just a follow-up on this. Last month I went to exercise the generator and it wouldn't turn over, run the fuel pump, or respond at all. Did some testing and everything checked out (voltages, good connections, starter solenoid) but I couldn't really test the control board. Since I already suspected it had issues I ordered a replacement from flightsystems.com, installed it today, and now it's working like it's supposed to again. So yes, the issue was a bad control board.

[Mikmal]

Thanks for the update.

[MJC62]

Originally Posted by atreis

Just a follow-up on this. Last month I went to exercise the generator and it wouldn't turn over, run the fuel pump, or respond at all. Did some testing and everything checked out (voltages, good connections, starter solenoid) but I couldn't really test the control board. Since I already suspected it had issues I ordered a replacement from flightsystems.com, installed it today, and now it's working like it's supposed to again. So yes, the issue was a bad control board.

Tx for the update!
May I inquire, what did the control board set you back?

[craigd853]

Originally Posted by MJC62

Tx for the update!
May I inquire, what did the control board set you back?

Hello, I bought one 1.5 years ago. Cost was about 750.00 dollars, hope this helps.