Generator/Propane Delivery Problem?

[2thrver]

I have a 2014 airstream interstate ext with an Onan 2.5 generator with about 104 hours on it.
Here’s the problem:
It cranks and starts, but immediately stops. Sometimes it will start and run for a few seconds and then stops, sometimes it stops immediately after starting. One time it ran for a few minutes before stoping.

I took it to a Cummins/Onan dealer and here’s what they did:
They originally thought it was ignition coil.
-Ignition Coil and associated parts replaced and spark plug replaced.
Still wasn’t working and they got an error code indicating the control board was bad.
-Control Board was replaced.

Generator then worked good on the bench. They connected generator back to RV and it would not start again (acted the same way it did before I took to shop).

They left generator on the RV and connected it to their propane tank and the generator worked good. We ran the AC and microwave and the generator continued to run well.

Connected the generator back to RV propane and it would not start. The stove top burners would work, but the generator was still acting as it originally did.
He changed one of the propane hoses that appeared to be kinked, but that didn’t resolve the problem.
He checked the regulator and said it wasn’t working properly and needed to be replaced. They didn’t have one and I had to leave, so I figured I could get a replacement and change myself. Later I replaced the regulator and it’s still acting the same way it originally did.

The propane switch is flipped on and the tank is full. The stove top burners work.
The battery disconnect is on.
The inverter is off.
The house battery at 100%.
I’ve tried starting the generator with the vehicle engine on and off.

Any suggestions on what the problem might be or where I could go to have it looked at?

[Harv]

I would think there is another restriction in the line somewhere.
Could it have been plumbed wrong? Did it ever work right? Should it have tank psi or regulated psi?

John

[2thrver]

I ended up taking it to a local RV repair shop. There he found several issues: fuel lines weren’t tight, spark plug gap was gapped incorrectly, spark plug wire end cap wasn’t screwed in all the way, and oil drain plug was loose. He fixed the issues and it worked good for 2 days and started having the same problem. Took it back and he realized Cummins/Onan dealership had installed the wrong type of spark plug. He installed the correct spark plug and it’s worked on several weekend trips without issue.
$2,000 for the Cummins/Onan dealership work.
$230 for the local RV repairman work.

[Russ Abbey]

If it was me I would keep the service people who did the job right and let them be your full time mechanics! I have found over the years when mechanics start replacing parts with no clue, it's probably going to cost me dearly. So I tend to go to the small shops to have me vehicles fixed. Works great and if they can't find the problem they say so and no charge unless they have spent a day working trying to find the problem.

73

[55AS]

Originally Posted by 2thrver

I ended up taking it to a local RV repair shop. There he found several issues: fuel lines weren’t tight, spark plug gap was gapped incorrectly, spark plug wire end cap wasn’t screwed in all the way, and oil drain plug was loose. He fixed the issues and it worked good for 2 days and started having the same problem. Took it back and he realized Cummins/Onan dealership had installed the wrong type of spark plug. He installed the correct spark plug and it’s worked on several weekend trips without issue.
$2,000 for the Cummins/Onan dealership work.
$230 for the local RV repairman work.

That sucks. I would look for some relief from Cummins...