Onan 4000 fault codes

[NanMWright]

I'm boondocking in Quartzsite (only once) and I don't have solar so I'm using my Onan 4000 about an hour in the morning and an hour in the evening. I've only put about 30 hours of use on it since it was serviced in February. The oil is clean and full. It now runs for about 10 minutes and shuts off with a blinking light that's 3 pause 6 pause 3 pause 6...etc. I don't have a manual and so I'm not sure of the codes (nor could I really fix it myself out here in the dust of the desert).  Quartzsite has closed down for the summer so no repairs here. I think I'll have to pull up stakes and head to a city where I can find repairs, but any suggestions you folks can provide would help quide me toward the most likely cause, and reasonable repair.

Thanks, as always....Nan

[manholt]

Cummins has a 24/7 tech help.  Give them the code, I don't remember what my code was, when my Oil level sensor went bad, but it did what yours is doing!  The sensor is around $35 and about 30 minutes to replace.

[dickandlois]

Nan, A 36 code is often related to fuel issues. How much fuel in the gas tank? If below around 1/4 tank -the level might be below the fuel pickup point, but the pickup point could be in the 3/8 tank range.

 This is intentional so one can get the coach to a gas station. Chassis engine has priority when it comes to fuel.

Check fuel filters, Air filter, proper oil level, Fuel pump is running. The fact that it runs for around 10 min. could also indicate a low coolant level and the electronics control board is over heating and that could also be turning off the generator. Sometimes that board will offer up a 36 code also.

This is some information on the QG-4000 unit.

There is also a Microquiet 4000 series.

Rich.

 

Onan QG 4000 Generator Spec and contact information_a-1399.pdf

[NanMWright]

Thanks for your input.  I'll contact the Cummins tech help, and run through the list of possible problems.

Thanks for the  .pdf.  I actually have the Microquiet 4000 series, so I'll see if I can find that manual online. 

Here's a question: the Onan seems to run okay in the cool morning, but in the afternoon when the ambient temperature in the desert is up in the high 90s, it shuts down. DickandLois, you mentioned that the control board could be over-heating...could this be from the ambient temperature of the desert, not just the running of the generator?

[Time to go solar, I guess.]

Thanks again folks. I always count on you to help me find the solution.

Nancy

[dickandlois]

Nancy, this is the Operators manual for the Microquiet 4000 series. 16.8mb PDF file

The fact that the generator runs when cool and has an issue when it gets into the 90 degree range says volumes about the unit shutting down when it is hot. So make sure that the air flow is not restricted and run a low load on it in the middle of the day.  Also keeping the Roof AV unit(s) clean and the Evaporator coils clean. The Evaporators are made of Aluminium - So use Extreme Simple Green mixed at 1 part soup to 13 parts of water in a spray bottle to clean the evaporator with the plastic weather cover removed. So you can clean bothe sides of the evaporator well.

Opening the Generator compartment door might help keep it cooler also.

You should be able to order a gallon from Walmart Special order or from Grainger  Supply company.   https://www.grainger.com/ Should be a location near you also. Store pickup with no shipping.

Rich.

 

onan-microquiet-4000_Operation_Manual.pdf

[jleamont]

Nancy, when it was serviced do you know if the following were addressed?

Spark Arrestor cleaned

Spark plug replaced

Air filter replaced

Oil changed

Fuel filter replaced

Is yours fueled by gasoline or LPG?

If you have the paperwork it might help to look down the parts list to see what was done when it was serviced, it could help narrow down the possible culprit. 

 

[NanMWright]

Thanks for your suggestions on the Onan. I'll follow up with each of them and see where it leads me. As always, I'm grateful.