Cummins Onan generator surging, stalling, overheating? Try this! If replacing your fuel pump and filter doesn’t work, you may be experiencing fuel vapor lock! This fix costs almost nothing and will probably fix most of your guys issues.
Nice vid! I have the same unit in our horse trialer except mine's on the roof with an insulated cover. It ran fine for several years but now experiencing similar problem.
Great video !!! I just bought an older toyhauler two weeks ago including an Onan 4000 generator which wasn't running anymore. I got it running now, but it shuts off after a couple of minutes here in the Las Vegas heat (vapor lock). This could be caused by an exhaust problem on that generator or simply because of the bad design with the fuel pump inside the generator housing. Tomorrow I will check it again, maybe I will also have to move the fuel pump to a cooler location. Sadly I do not have as much space like on your RV to do this. Thanks again for this video :-)
I’ve heard of people relocating to underneath the camper as well or closer to the fuel tank actually since fuel pumps are designed to push gas not pull. Good luck!
@@dom_offroad I think when the pump is just out of the generator housing it should be OK even further away from the tank. I checked mine again today and even after I fixed the exhaust, the generator shuts off after a few minutes. The fuel lines do not feel that hot, but the fuel pump itself is too hot to touch. It is an aftermarket fuel pump and not the original Onan. Not sure if this is also part of the problem. However, I will install the pump further away from the heat now.
I have the same issue runs for 5-10 min then shuts off. Campers just over a year old. I’ve checked the oil and replaced the pump and filter after it shuts off won’t restart and no fuel issue. Crazy thing is it will do it at 70 degrees also.
Just an update about my situation with the Onan. So I also changed the fuel pump location to a much cooler area outside the generator housing. I got it running a bit longer but then I had a vapor lock again. I noticed that the new but cheap fuel pump from Amazon was getting very hot even outside of the housing. So I switched back to the super old original Onan pump. Then the generator running time went from 3 minutes to 9 minutes. But this was in the Las Vegas heat (100+F). Later I tried it at a cooler place and at 70F the generator runs perfect there. However, I will need to replace that old pump with a new original Onan pump in the hope to be able to run the generator at warmer weather. But in general I learned that two things are key: 1.) install the pump outside the housing 2.) buy an orginal pump and not the cheap stuff in this case.
@@swegotech8466 so I’ve also heard of people installing the fuel pump close to the gas tank as fuel pumps are designed to push fuel not pull. Might be a good idea since you’re still having issues to try and relocate to where the fuel tank is. Good luck!
That's my problem. i live in AZ, and i ran mine for 15 mins and it cut out. tried to drain the bowl, and no fuel came out. . Wait 30 mins and starts back up. Thanks, I'll do the same.
I’m thinking this is my issue as well. Mine runs fine when the doors are open and it’s cool out but only runs about 5-10 mins when it’s above 90f ambient. Thanks for the video!!!
So glad I found this video. I am in Florida too, and my gen did the same thing when hot outside. I was on a similar line of thinking, and was going to install a new pump, because I figured when it got hot it would stop working, but I also new it was working because it would immediately start again then quit in 2 min. I will make this change but not looking forward to it in this florida heat. I might wait a month when I travel north 1200 miles where it is a bit cooler.
I was just wondering as to are you using or leaving in place the old pump and filter and adding this new one outside as you show it? not clear? I assume you are using old? looks hard to get removed and adding extra length fuel line to front? Thank you Lookinh great.
My generator has same problem … last summer gave me same troubles…. When the winter came went back to normal good running but now since the weather is warming up started to create problems again … i
I’m still having issues as well, I bought a second fuel pump I’m going to put near the tank to send fuel to the pump at the generator. I’ll post a video of the install and how it goes.
@@ddoud my problem was the fuel pump . I purchased new pump from Amazon $42 and changed it ( took me 30 min ) . My generator runs now like a brand new generator.
