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Onan Generator Won't Stay On?

April 19, 2018, 07:50:27 pm

Hey Ya'll (I'm in Texas... required to say Ya'll now),

I'm stopped at a rest stop with no hook-ups. Figured it was a perfect opportunity to give my Onan Emarald III Genset a workout (65 NHE-1R / 26100A).

It started up like a dream. Took a few moments to get up to voltage. Transfer switch kicked on like it's supposed to. We had power. We ran the AC on the front AC, ran the Fan on the back, and even hooked up the gaming system and played a little with the kids. All good.

Generator seemed to be running a little rough... as in it doesn't sound consistent if that makes sense. And my voltage meter in the way was reading a bounce from around 105-110 under load.

Then it shut off... died.

Turned it back on. Ran for another 15 minutes. They died again.

Now... it won't turn back on. It'll turn over and "run" as long as the start button is held in... but as soon as you let go of the start button it shuts off.

Any ideas? I've got nothing.

I did a full service on it. It's got new spark plugs, new oil, new oil filter, new oil filter.

Also, shot a quick video so you could see/hear what it's doing:
YouTube

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Re: Onan Generator Won't Stay On?

Reply #1 – April 19, 2018, 08:27:47 pm

It could be a fuel problem. Has it sat unused for several months? If it has the carb may have bad fuel in it that has plugged up the jets in the carb. It could also be a bad fuel pump. Do you have more than 1/4 tank of fuel?

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Reply #2 – April 19, 2018, 09:23:33 pm

Gas, diesel or propane??  Hard to make suggestions if you don't know fuel type.  Have a great day  ----  Fritz

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Reply #3 – April 19, 2018, 11:52:55 pm

I would hold the throttle manually like you did in the video and if it runs okay then it's probably something to do with the shut off.
Do the gas generators give up any codes.

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Re: Onan Generator Won't Stay On?

Reply #4 – April 20, 2018, 12:01:25 am

Check the basics first,does it have fuel,oil,enough coolant,fuel filter.Looks like it's covered in red dirt,try blowing some of that dust off.Looks like it's gas powered to me.

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Reply #5 – April 20, 2018, 12:23:04 am

They are gas, and air cooled. Low oil will prevent running. These generators had control board problems that Flight systems repaired.

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Reply #6 – April 20, 2018, 12:45:54 am

Oil pressure switch/sensor can cause issues like this.

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Reply #7 – April 20, 2018, 08:05:43 am

It's gas.

The red dirt is from a dust storm we we in the other day... was curious if I could hose it off?

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Reply #8 – April 20, 2018, 08:27:13 am

I had a similar problem a couple of times with my Emerald III on my 93, U225. Worst case scenario was it needed a new voltage regulator, about $150 repaired by Cummins SW in OKC. The other simple problem was that an insect had gotten into the vent of the propane regulator. I simply took off the vent tube and cleaned it out, but I understand your genie is gas so this may not apply.

Good luck.

Oh and don't take it to Camping World. They wanted to charge me almost $500 for the voltage regulator.

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Reply #9 – April 20, 2018, 02:34:23 pm

Something similar happened to me once. My generator was low on oil.

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Reply #10 – April 20, 2018, 04:13:29 pm

I would not put a hose anywhere near the generator,if there is no oil or gas residue on it try some air from a hose,it will probably
get most of the dirt off.Are you sure it has enough oil?

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Reply #11 – April 21, 2018, 01:19:18 pm

If you manually hold the throttle open will it keep running?

Just from the video I'm thinking the fuel pump. Those are notorious for failing in their later years. You can get one on ebay about $60.

Good luck.

see ya
ken

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Reply #12 – April 21, 2018, 01:49:38 pm

Holding the start button may bypass shutdowns,don't want to hold it too long.

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Reply #13 – April 21, 2018, 02:46:46 pm

As others have posted, check oil level and wiring from sender. Here is the user manual: http://campkahler.com/files/onan/NHE-A-C-Service.pdf

Gasoline engines don't like long periods of storage and the fuel system is frequently the culprit when it does not run well. Could be pump like Ken posts too. Carb looks pretty easy to pull and use a spray cleaner on the inside, float, etc. Good to have a filter on the feed hose too.

Pierce

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Reply #14 – April 21, 2018, 08:13:14 pm

I just had a thought that maybe the points and condenser need to be replaced. The condenser may have gone bad. which could be causing it to misfire..

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Reply #15 – April 21, 2018, 08:18:30 pm

If holding the start button in keeps it running that eliminates fuel and spark. That leaves the sensors or the control board. I had to replace the control board on my Vogue to solve the same issue.

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