Onan generator quits running 2016 Sightseer

[Brooks]

My Onan RV QG 5500 won't stay running I pulled the pump off and it is pumping gas the oil is full I am getting codes 3,15,and 36. It will run for about a minute and then shuts down

[Eagle5]

Hi Brooks,
I have moved your generator question out of the Welcome Mat to the General Maintenance and Repair category. It should get a little more attention here.
Thanks, Eagle5

[wahoonc]

According to the code list:
3 service check
15 Under Frequency
36 Engine Stopped

Quite often the 15 code is caused by too much load on the generator causing it to bog down. Try turning your main breaker off on the converter and see it it will start and run. If that works turn all the breakers off, start the generator and turn them back on one at a time.

The other possibility is something haywire in your wiring.

Aaron

[Morich]

I would read those as caused in this order:
3 Service check. Maybe an air filter is not changed and not passing enough air?
15 Under freq. The engine is not running fast enough! Maybe because it is not getting
enough air?
36 Engine stopped? YUP, it shuts down if it can't run like it should!

That may be way too simple but I would look for the common items first!
You've checked the fuel but it needs air , too.

[Brooks]

Originally Posted by Morich

I would read those as caused in this order:
3 Service check. Maybe an air filter is not changed and not passing enough air?
15 Under freq. The engine is not running fast enough! Maybe because it is not getting
enough air?
36 Engine stopped? YUP, it shuts down if it can't run like it should!

That may be way too simple but I would look for the common items first!
You've checked the fuel but it needs air , too.

Yup checked air cleaner it is good

[Morich]

Ok, moving on to things that might be less obvious!
I might want to take a look at the wiring from the monitor or control panel to see that there is not something lose, making the generator think you have hit the stop button?
Can you get in to see any plugs where the RV wiring meets the generator wiring, maybe take the plugs apart to see if it looks corroded, etc. Maybe even worth some contact cleaner on anything that looks suspect?
From there it gets way out of my range as there are boards and controls on generators that are a whole different field for me.

Sorry, the long shot guesses are about as close as I get to generators!

[bigb]

My Onan is actually diesel but I had an ongoing problem where it would just shut down for no apparent reason. I eventually removed the fuel line from the pump output to test fuel delivery. It passed the fuel delivery volume test so next I submerged the line in a glass container with clean fuel to check for air and I found lots of air bubbles that didn't clear up. (you have to do it long enough to clear the air from the open end of the line) It turned out to be sucking in air where the hose attaches to the pump inlet. I cut a fresh end on the inlet hose and reattached it with 2 fuel injection clamps. The factory uses regular worm type clamps which do a poor job of sealing as they don't provide even tension all the way around.

That was in August, in September we took a trip and ran the generator with no shutting down problems, we ran it for about 4 hours on the highway.

[Four Seasons]

I had a rough-running, then completely quitting episode this summer. After trying everything else I could on the road, I fiddled with the altitude adjustment and away it went! Runs great ever since. I am guessing some dirt got caught in there... or it had vibrated into the wrong position. I don't really know... it was dark outside!

[Jakm]

I think Gil has your answer with the altitude adjustment jet. I had the same issue, would run for a minute or so and shut down throwing codes that made no sense. I stumbled across an excellent YouTube video on the subject and made my jet adjustable as described in the video and am very happy with the results. I have also become more prudent about routinely exercising the generator and draining the carb bowl after each use.

https://www.youtube.com/watch?v=SiJXLL0Lfy4

[Four Seasons]

Originally Posted by Jakm

I think Gil has your answer with the altitude adjustment jet. I had the same issue, would run for a minute or so and shut down throwing codes that made no sense. I stumbled across an excellent YouTube video on the subject and made my jet adjustable as described in the video and am very happy with the results. I have also become more prudent about routinely exercising the generator and draining the carb bowl after each use.

It might also be worth mentioning, I had just dosed the RV gas tank with GumOut a few days earlier, in an effort to quiet some valve chatter in the truck engine. That could have dislodged some gunk in the fuel line, filter or carb. I have always run the generator under 2/3 load for a couple hours every month, regardless of other usage - but now I think I am going to switch up to 1 hour every two weeks - and use the GumOut spring and fall. I used to use some Seafoam once in a while, but the GumOut gives a noticeable improvement in truck engine performance.

[Bo Walker]

When my 4000 did that, I had to replace the voltage regulator.

[Fred 2106DS]

Hopefully one of the above suggestions solved your problem. If not, I would suggest replacing the low oil pressure sensor.

I had the same problem as you with my home portable generator.

I don't know if you can bypass the sensor on your generator to see if that is the issue, I was able to on my generator and the generator ran like a champ. Replaced the sensor and haven't had the problem since, but I also keep a spare on hand just in case.

[Don G]

Fuel Filter?