Accessing Onan fuel line at a 2004 Destiny gas tank

[Blue~Go]

I grew up with good-old 2-strokes as well. We ran them dry in the fall and returned the next summer to motors that ran fine (we did of course do other maintenance). The good old days I guess.

As I understand it, the deal with modern 4-stroke engines (especially small ones) might be that the jets are super small? Combine that with maybe modern fuel varnishes more and they easily get clogged (I don't know for sure.) If you've ever paid to have four carbs rebuilt or replaced you (or at least I) start draining them religiously! It doesn't hurt that they are at eye level and easy to reach with the motor cowling off (nothing struck me as that easy to reach on the Onan, although I was only disconnecting things not maintaining it). I mean, it's about two easy minutes' work.

I guess I assumed the carbs were right-side up since the drain screw seemed to be near the bottom, but I confess I don't know for sure. Maybe just because that's how cars were?

[markatherton]

The ethanol in gasoline is really hard on fuel lines. I see some of them eaten up in only a couple of years. The parts suppliers have a more resilient fuel line they sell for ethanol. You have to specifically ask for it, and even then some of the "know it all" parts guys will look at you like you are stupid.

[Scott]

Pretty funny that we were having this exact conversation two years ago! "Varnish" is a term too gentle. I couldn't get this carb clean to save my life. Honda rototiller. I still miss it.

goooo.JPG (38.46 KiB) Viewed 4278 times

[dougm]

I bought my generator direct from Cummins/Onan while i was in Minneapolis. Initially i was quite pleased with it. It would fire right up and run good without any issues during the winter months if i needed it. But then i went on a trip with my two dogs during the summer to a lake. The humidity was terrible so i took the dogs swimming most of the day but i eventually got worn out so we got in the Chinook and i started the generator to run the AC. After about 15 minutes the generator shut off and it wouldnt start again. I checked the obvious things and found nothing wrong, after about 30 minutes it started again so i got back inside and turned on the AC again, wasnt more than 10 minutes and it died again. I packed up and drove to the nearest town and bought a new fuel filter and oil, changed them out in the parking lot but the generator still wouldnt stay running so i had to cancel my weekend and head home because it was just to hot for the dogs. I still havent been able to pinpoint what causes it and have resigned myself that i simply wont have AC if its hot and humid outside unless im plugged into shore power. I can only assume that temps in the 90's combined with high humidity is more than the Onan can handle. Quite disappointing to say the least after spending $3000 on a brand new generator and another $900 to have it installed at the local RV dealership. No, im not impressed with cummins/onan in the least. What good is a generator if it cant be relied upon to work properly when you need it the most.... IMO they are garbage. I wish Honda or Yamaha made a replacement for it.

[BobW9]

Dougm, if you haven't already, I'd replace the entire fuel line from the gas tank (i.e. make sure they don't do what I later found my shop did and cut the line where it goes through the compartment wall and splice it, because "It's only 6 inches, that can't be the reason", lucky for me that part was/is apparently okay).

In my 2000 it looked okay, but apparently had deteriorated to the point that based on bouncing around while driving and heat/humidity/whatever, it would or would not start when I arrived somewhere. It could be that in your case it starts out cold and dry, and then as it gets wet from the gas, some moisture, or just air, comes in through cracks in the rubber.

In my case, I took it in to Cummins, they tested it all over and said it was in great shape and always ran fine. But they do not deal with anything outside the generator, and were using their own gas and gas line, and the onboard generator's switch and their own electricity for starting. Finally I took it to yet another RV place and argued with them until they replaced the fuel line (like 2 previous places, they argued the line looked perfect and couldn't be the cause). Has worked great since then.

Given that your generator is new, and in general these are good quality generators, I think its worth a try.

[chin_k]

I agree with Bob about looking into the fuel line, Doug. How far are you from Minneapolis? Isn't your genset still under warranty? Did you contact Onan with your issue and how did they responded? Our rig is certainly not spring chickens, and installing the genset on it may encounter problem not Onan's fault. I can be the installer kinking the fuel line by accident for example. Given that you have a new genset, and have it installed professionally, I feel you should look more into this and get it resolved.

[Alfie Farrand]

After searching for a shop to inform me what is wrong with my generator I finely went to a Ford dealership.
A smoke test was the reply so $200 later a roll over vent valve was the culprit they informed me. Take the black water tank off then the gas tank and repair the bad part, how much was my reply $2000 so I picked up my family jewelry off the floor and went in search of a professional shop.
$585 later the vent was fixed, the tank was dropped, and a new fuel line to the generator was installed. She’s , now purring like a kitten. Moral of the story, keep looking for a great mechanic in a great shop, they are out there.
Thanks
Alfie