Onan Generator service options

[PCW2994]

I have a KY 4000watt generator on a 2019 entegra esteem 29v.
generator will start after prime, but stops in a few seconds. it comes up code 36.
Took it to nearby Ford truck service center that is Onan certified. They determined the carb needs replacement. Carb is $500 and labor including assessment is $500.
Is this normal??
There has to be a better option. I would tackle it myself, but i never worked on one of these.

Thoughts?

[jl.kauai]

There should be YouTube’s on this. Not that difficult. When you get it repaired be sure to exercise it regularly. Good luck. Travato John.

[ViperJD]

PCW, a quick search on the code 36:

Code 36 means the engine stopped without a shutdown command from the Genset control panel. This could be caused by a bad fuel pump, clogged filter, crimped fuel line, dirty carb, out of fuel, etc. You will first want to check for these potential causes on the fuel system side and mechanical side of your generator.

So, if you don't want to go right to the carb, try a new fuel filter (and re-prime). Also depending on how often you use (2019 with xxx hours???), you might try a carburetor cleaner if the new filter doesn't work.

Best of luck,

[Lt Dan]

Changing the carburetor should be an easy change and here's an aftermarket one on Amazon for less than $35.
https://www.amazon.com/Carbhub-Carbu...iet-4KYFA26100

The fuel pump on these is also an easy change and here's a fuel pump and filter kit for $26.
https://www.amazon.com/CNRAQR-Genera.../dp/B0DHVDBQ2K

I would change the fuel pump first as that's a common problem with the Onan gas generators. I had the same issue with the 5500 generator on our Itasca and a new fuel pump fixed it.

[ChrisDParise]

Check that the throttle linkages are free from debris. Mice love to build nests on top in the back and it doesn't take much debris to hinder the linkages from operating properly.

Try blowing compressed air in the compartment to clean it out. Try to avoid blasts of air right on the linkages

I don't remember my codes but thats what happened to me in 23. I took mine to my dealer who's also an authorized Cummins service center and they found the debris. Very strange because I do all my annual oil changes and looked for any debris and missed it I guess.

Only cost me $140 and worked fine all of 24. About 800 hours on my 2006 same model as yours

Good luck

[George Schweikle]

Agree with checking YouTube videos. Some of the best for motorhomes are by Kevin Caudill and he may have one for your specific generator problem.

Originally Posted by jl.kauai

There should be YouTube’s on this. Not that difficult. When you get it repaired be sure to exercise it regularly. Good luck. Travato John.

[jacwjames]

FWIW,
My wife was on a solo trip to dog show in June. I had done a service on the generator prior to her leaving, Oil & Filter, air filter, and new belt. Test ran it for ~1 hr prior to her leaving. It ran fine the first day. On the second day it wouldn't start but she had reservations at campground and then power at the dog show for 4 days.
While at the dog show I had her do the diagnostics, came up with the same code 3-6. Had her change fuel filter, nope still wouldn't start. She did a face time call and when I listened at her trying to start it didn't seem like the pump was building pressure.



So I made arrangements for her at a Cummins shop, told the shop scheduler that I thought it was a fuel delivery problem. Wife pulled up to the shop, since she had dogs they agreed to work on it outside. The generator is on a slide so pretty easy access. Tech tried to start, nope. He decided to bypass the fuel tank and attached a small tank with clear hose so he could see if fuel flowed, not fuel when priming. So he changed the fuel pump. Fuel pump cost $250 & labor was $600.

After market fuel pump can be purchased for ~$75, which I plan to buy and carry.





In your case the carb may be gummed up. My brother does small engine repair. He sees this a lot when people use something and don't run the full out of the carburetor by shutting fuel off and running engine until it dies. He uses Seafoam when he winterizes engines in lawn mowers, ATV's, snowmobiles, inboard/outboard marine engines, >>> pretty much everything.

So you could first try a fuel additive to clean out the carb but if it is gummed up bad it may have to be removed and cleaned BUT some of the new carbs aren't servicable.

The carb usually isn't hard to replace if it is accessible. YouTube is your friend, if you are willing to take the time to do searches and have the correct tools.
I usually use working on my coach as an excuse to buy NEW TOOLS. Easily justified if you are able to fix the problem.

[MtCamper]

I'd recommend clamping off the fuel line and using a 1 gal container as your fuel source. Drop the bowl from the carb and make sure there is no crud in the bottom and replace. Put an entire can of SeaFoam into the gallon of gas. Prime the system and try to start. If it starts, let it run a few minutes and then let it sit overnight. If no start, let it sit overnight, drain and try again. You may need to use a little ether to get it to run, but be careful, a backfire may burn down your coach. Eventually it should run. Pour the rest of the gas into your fuel tank. Add a shutoff to the fuel line as it goes into the carburetor. Use the shutoff to run the carb dry for long term storage.

[100amp]

Just had the same problem with my Onan 4000. New carburetor - fuel pump- and filter all from Cummins $678 put it in myself runs like new. DO NOT BUY ANYTHING FOR IT ON LINE YOU WILL BE SORRY YOU DID

[100amp]

Run gen once a month under load for about 45 mins to hour is recommended by Commins

[baraff]

Probably a silly question but do you have more than 1/4 tank of fuel on board? These generators are designed to shut down if tank level drops below a 1/4 tank so that you don't get stranded somewhere remote.
A lot of people forget about that last 1/4 tank.

[SteveJ.]

Originally Posted by 100amp

Just had the same problem with my Onan 4000. New carburetor - fuel pump- and filter all from Cummins $678 put it in myself runs like new. DO NOT BUY ANYTHING FOR IT ON LINE YOU WILL BE SORRY YOU DID

I've been using a $40 carbbie for 4 years, 135 hours. I did have to reattach the throttle bell crank about 2 years ago.

Using an externally mounted universal fuel pump:
https://www.amazon.com/gp/product/B0...e?ie=UTF8&th=1

[sibe]

GET OEM cleaned by a old school carb guy, the float/gasket kits are around $50-65.. onan..
After 3 knock off carbs... I had old one tanked/cleaned proper.. It runs like a champ.. I did mount a new fuel pump outside the genset.. also a fine micron fuel filter inline 6 inches from the carb...

I also run mine every 3-6 weeks,, depends if I remeber.. LOL,,

[PCW2994]

Thx for all the great info.
I'm only a couple years into motorhome usage. This site and members are a fantastic source.