Onan diesel gen problem

[jtad]

So we bought a new to us 2004 Holiday Rambler Endeavor. It has a 7500 Onan with 570 hrs. Picked it up yesterday. Gen started right up and ran perfectly. That was at 4PM. It ran non stop without problem till about 5AM. It just died, cranked on it 7-8 times. It would just spit and sputter, then started right up. Ran non stop till about noon today..Died, same thing spit sputter try to crank then fired up and ran for 15-20 mins died again, same thing, run for a few mins then die.. Finale started back up and ran no problems for 3 more hours. Pulled in the driveway..died..spit sputter..start back up. When you are trying to start it, it acts like its not getting fuel, lost prime or something. Any ideas??

[azrving]

jtad wrote:
Well update. I haven't had a chance to look at it till yesterday. Crawled under it to check it out. First thing I find is the fuel line is kinked almost completely closed. I have no idea how it would even run. Some minor work was done to the geni at a dealer, when they put the cover back on they didn't screw the clamp that holds all the wires and fuel lines back onto the cover. So they were all just hanging there, with the geni pushed in it had the line kinked..

Good to hear that. Too bad it was created by the people who are supposed to fix it. It is always best to start with a visual inspection and backtrack to what may have been done last as it can often be related.

[jtad]

Well update. I haven't had a chance to look at it till yesterday. Crawled under it to check it out. First thing I find is the fuel line is kinked almost completely closed. I have no idea how it would even run. Some minor work was done to the geni at a dealer, when they put the cover back on they didn't screw the clamp that holds all the wires and fuel lines back onto the cover. So they were all just hanging there, with the geni pushed in it had the line kinked..

[lj2654]

should be a plate right on the front side of genset for model #......I agree fuel line possibility or fuel filter......good idea to check the air filter too. When we bought our DP used the owner said he had just serviced it. I pulled the air filter out to check it and there was a ton of sand in it.

[jtad]

cummins is a mile from me. Camping world is like 20.

[SCVJeff]

Even Camping World has those filters on the shelf

[jtad]

I am at work today, but there is a cummins/onan dealer right around the corner. Where would you find the model number of that gen set so I can explain to the wife how to go get the number for me. I will stop and get a couple of filters in the AM.

[Big_Katuna]

Change the fuel filter and retry.

[azrving]

At that age it could be very likely that it has a bad fuel line and is sucking air. It could be very erratic with no pattern, that's what suction side issues act like. I would do the fuel lines and filter and see what happens. Even if that's not it, you are not wasting any money as rubber components are a maintenance issue anyway.

[KD4UPL]

I would say you have an air leak somewhere. It could be a loose fitting or hose, a cracked hose, a loose filter, loose bleed screw, etc. It might be hard to find. I'd follow the fuel line from the tank and look for signs of leaking fuel.
I'd replace the fuel filter too, their cheap and it's good maintenance since you probably don't know when it was changed last.

[jtad]

Fuel tank is full.. There is no pattern to when it does it. Might be 12 hours might be 12 minutes. When you try to restart it acts just like it has lost prime.

[Valkyriebush]

SCVJeff wrote:
How much fuel is in the tank?

You need at least a fourth of a tank of gas as the generator is designed to only draw fuel until your tank is one fourth full. That way you won't run out of fuel if boon docking.

[sdianel_-acct_c]

If it's not the fuel filter,
We had a hole in our fuel line going to our Onan generator. The generator gives a fault code. The Cummins service center we took ours to diagnosed it in about 5 mins. They had to replace fuel lines. Quick service, reasonable price. There is a Cummins service center in Fort Worth. They might be able to help you diagnose it over the phone.

[SCVJeff]

How much fuel is in the tank?

[Jamboree89]

Probably need to change the fuel filter.