Cummins 4KY-6747R problems

[Randall kjose]

I have a Generator problem in my 2022 25G momentum, its only got 17 hours on it, and most of that is from running all night one night a year ago. Other hours just running once in a while. The thing is the Generator runs and start right off but only will run about 5-10 minutes and then starts surging until it dies and then you have to wait until it cools off before it will start again. I know it’s probably got a low oil shutoff on it, could it be that when it gets hot and the oil gets thin that it shuts off? It runs good otherwise up to. A point of when its hot. Any other ideas that would cause this pronblem.

[TucsonJim]

Hi Randall.

This sounds like you may have carburetor issues due to stale fuel leaving deposits. When you stored the rig, did you use any type of fuel preservative such as SeaFoam or Stabil?

The reason I suspect the carburetor is that it's stalling after a few minutes. Typically, when the unit first starts, the choke kicks in. When the choke is on, the carburetor has less air flow, so it will typically run. When the engine gets warm, and the choke turns off, the fuel to air mixture is too lean and it surges and stalls.

There are ways you can try cleaning the carburetor with SeaFoam. If that doesn't work, the carburetor may need to be pulled and cleaned or replaced.

This is just me thinking the problem through, and there may be other causes that are in play.

Jim

[Jlawles2]

Double check the fuel supply lines, Seems like someone had a similar issue a while back and they determined the generator was having to suck fuel from the tank and as the generator heated up the fuel line to the generator was in an area that would cause it to get "warm" essentially leading to a "vapor lock" once everything cools back down, life is all good again.

[Randall kjose]

Fixed the problem which is pretty common among those with Cummins Onan generators. After watching you tube many had the same issues and it’s to much oil in the motor that effects the sensor that shuts it off if low on oil. Well it also effects the shutoff if theres to much oil. I took out about 4 turkey blasters full of oil, now when you check the oil some say don’t screw the dipstick back in to check the oil, just sit it back in the hole and check it which some manuals say one way of=r the other. Anyways the oil was in the middle of the dipstick between high and low and it ran and ran with no hesitating, and started after it was warm which it wouldn’t do before. Many YouTubers had the same problems and spent thousands on everything with no avail and all it was was overfilled with oil. Thanks to Nomadic fanatic for his telling of the story and fix.