Onan Shutting Down

[kappy1168]

That is one of the fixes that was proposed but it sure seems impractical. They would have to start moving all kinds of other things around (holding tanks, etc.) and I certainly don't want to lose any storage space which is already limited. We'll see if this Side Diverter Discharge kit does anything. Not even sure what it is or what it's intended to do. Thor rep had no idea either.

[carlgorski]

Mine did same. Had to adjust altitude knob.

[mh22776]

If generator is on the passenger side the exhaust is in front of the intake causing it to suck in hot exhaust. Onan has a mod for this problem about $200. My 2015 34e gen would shut down in hot weather.

[kappy1168]

My generator is actually on the drivers side right behind the driver but I believe is doing the same thing, sucking in the hot exhaust but from the motor home engine. It is still under warranty and the dealer (working with Thor and Cummins) recently installed a louvered vent of sorts that installed on the bottom of the generator near the generator exhaust to redirect air flow. Is that the fix you are talking about? I've only been able to try it once when it was 85 degrees out and it didn't shut down. I won't really feel it's fixed until it doesn't shut down when it's 100 degrees.

[Bob Denman]

Let us know if it is still effective, when the temperatures get REALLY serious: good luck!

[kappy1168]

I definitely will. I know there are several others suffering from this annoying situation!

[kickingaz]

Originally Posted by kappy1168

My generator is actually on the drivers side right behind the driver but I believe is doing the same thing, sucking in the hot exhaust but from the motor home engine. It is still under warranty and the dealer (working with Thor and Cummins) recently installed a louvered vent of sorts that installed on the bottom of the generator near the generator exhaust to redirect air flow. Is that the fix you are talking about? I've only been able to try it once when it was 85 degrees out and it didn't shut down. I won't really feel it's fixed until it doesn't shut down when it's 100 degrees.

That is the repair Cummins performed on my Challenger 37KT. This was dropped off last June and they didn't complete the repairs until October if I recall the dates correctly. Needless to say, we did not have hot enough weather to test it yet, but at the end of this week we will be driving from Phoenix, AZ to Moab, UT and that will be a good test as temps will be in the 90s and perhaps 100s near Phoenix.

[kappy1168]

Thanks Kickingaz... please let me know what happens. I'm actually driving to southern NM this weekend and it's supposed to be in the upper 90's so I will get to do a test as well. I plan to run the genny the entire way down!!! Good luck to you as well and let's keep our fingers crossed!!

[JohnR13]

Joe-FL - in hot weather our Onan shut down while driving down the road running one air conditioner. CW diagnosed as overheating and their "fix" was to use a slightly heavier grade of oil. It worked until we drove through Southeast Utah in 100+ degree heat. Sure enuff, it shut down again and we had to use little fans inside the coach to blow cool air from the cab into the coach

[riskmgr]

Originally Posted by Joe-FL

This happened last fall and has now happened again. My 5500 Onan will run fine if just sitting stationary. Once you get on the road it will only run for anywhere from 15 minutes to 30 minutes before shutting down. I have looked at my fault code and it is of course code 36 (3 blinks and then 6 blinks).

I have read past posts on this forum and did some research online. For my model (2014 chassis/2015 coach - Challenger 37GT) it looks to me like this could possibly be one of three things. A defective fuel pump, inadequate air ventilation to generator compartment, or carb gummed up from lack of use.

I just filled the tank for preparation of heading out on a 7,000 miles plus trip in about 3 weeks. The first thing I am doing is inspecting and probably changing the air cleaner on the Onan and then adding several cans of Sea Foam to the tank.

For those that have had similar experiences with their Onan gen sets, what have you done to correct this situation besides taking it back to dealer or Onan facility?

The dipstick is defective on my Onan 4000. The Full line is too high and when the oil gets hot, it shuts down so I bought an oil extractor from Northern Tool for $10 and extracted oil from dipstick down to 1/4 inch above Add line. It corrected the problem.

[Joe-FL]

If I still had that coach I would have certainly tried some of these fixes. We have since sold our sticknbrick, traded coaches, and went full time.

So far traveling the first 2,000 miles this year we have needed to run the generator most of the time. These gen sets should work good no matter what coach they come on.

[riskmgr]

Originally Posted by JohnR13

Joe-FL - in hot weather our Onan shut down while driving down the road running one air conditioner. CW diagnosed as overheating and their "fix" was to use a slightly heavier grade of oil. It worked until we drove through Southeast Utah in 100+ degree heat. Sure enuff, it shut down again and we had to use little fans inside the coach to blow cool air from the cab into the coach

Try this: The dipstick is defective on my Onan 4000. The Full line is too high and when the oil gets hot, it shuts down so I bought an oil extractor from Northern Tool for $10 and extracted oil from dipstick down to 1/4 inch above Add line. It corrected the problem.
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[Thehobe1]

Could it simply be the oil level sensor is shutting the gen down as the oil level rocks back and forth during travel?

[riskmgr]

Originally Posted by Thehobe1

Could it simply be the oil level sensor is shutting the gen down as the oil level rocks back and forth during travel?

No, the dipstick is the problem. Guess Onan engineer was sleeping the day they were finalizing the build. The oil is overfilled then when it’s gets hot,, the sensor shuts it down. The Full line should be 1/4” above Add. I think of all the money wasted in fuxibg this problem. Maybe a class action lawsuit against Onan. Definitely they’re liable.

[sky_blue]

Originally Posted by Joe-FL

I am hoping it doesn't turn out to be anything as hard to find as that! Going to buy more Sea Foam today, not sure 2 cans is enough.

Joe, One can is enough.

[jtroop]

Originally Posted by riskmgr

No, the dipstick is the problem. Guess Onan engineer was sleeping the day they were finalizing the build. The oil is overfilled then when it’s gets hot,, the sensor shuts it down. The Full line should be 1/4” above Add. I think of all the money wasted in fuxibg this problem. Maybe a class action lawsuit against Onan. Definitely they’re liable.

Is this what you are referring to:

https://www.youtube.com/watch?v=vzXDlln8aUw

I will look into to this. Drove 18 miles the other day in 85 degree weather and it shut down again with sea foam added. Mine is a 5500, I hope this fixes the problem.

[riskmgr]

Originally Posted by jtroop

Is this what you are referring to:

I will look into to this. Drove 18 miles the other day in 85 degree weather and it shut down again with sea foam added. Mine is a 5500, I hope this fixes the problem.

Yes this was my problem. Bought an oil extractor for $10 and brought oil down.

[kappy1168]

So it seems that the louvered vent Thor provided that they installed to the underside of the generator near the exhaust may have worked. Made it from ABQ to White Sands and ran the genny the whole 4 hours down and the 4 hours back. It never shut down. Caveat: It was hot... mid 90's but it was hotter when I had the problem originally last summer. Still, a good sign. KICKINGAZ, I'm curious how you fared on your journey with the same problem???

[javelin]

Kappy1168 any chance of providing pictures of this exhaust louver solution? I have been reading older posts from 2014 where it seems that you cant provide just a louver in the generator coach door for the KY microquiet 4KW units since the generator exhaust heat (and Ford engine exhaust heat) can still be taken into the generator intake air vents. The solution seemed to be from having an intake air boot between the gen door louver and the intake air vent of the generator itself which ensures that only cooler outside air is taken into the generator intake. Perhaps diverting gen exhaust air away from the gen intake is the other option? It would be preferable to cutting holes into the coach generator door.

[jtroop]

Originally Posted by riskmgr

Yes this was my problem. Bought an oil extractor for $10 and brought oil down.

I am happy to report that this indeed fixed my Onan 5500 shutting down while driving. Last Saturday, I drove 62 miles in 95 degree heat and the genset ran perfect. Kept the coach nice and cool with AC on. Thank you for posting this solution. I can't believe all the money being wasted on this wide spread problem and it turns out to be an incorrect oil dip stick