Cyclone - Onan generator sucking air

[MrBill]

I replaced the fuel pump and filter on my Onan 5500 generator after I started getting error codes that the genset wasn't getting fuel. It ran fine for about two hours. Now I'm getting the same error codes. I took the fuel line off the carb and it seems like the fuel pump is sucking air. The fuel tank is over half full. To me this sounds like either a crack in the fuel line or the dip tube has fallen off inside the fuel tank. I don't want to drop the underbelly liner if I don't have to. This is on a 2008 cyclone 3795. Has anyone had this problem?

 

[porthole]

It is a rubber fuel line that runs from the tank to the generator, through the frame.
It may come up from the frame area behind the generator into the gen compartment. On our trailer the line was pinched at the wall separating the gen from the basement.

My thoughts - you have no choice but to inspect the entire fuel line, dropping the corroplast on the left side.

But, since your rig is a 2008 and you have had no choice but to use ethanol fuel in the last 10 years, the odds are in your favor that the fuel line has been comprised by the use of ethanol laced fuel.

If you are going to go through the trouble of dropping the corroplast to inspect - just replace it.

Replacing it may even be easier. You may be able to pull the line from the back to the front with only dropping the corroplast in the basement area.
The corroplast stops at the rear axles and the fuel line is visible from there to where it goes up tot the top of the tank.

 

[LBR]

^^×2^^....at 10 years, replace the gas lines even if that isn't the problem...

 

[MrBill]

It is a rubber fuel line that runs from the tank to the generator, through the frame.
It may come up from the frame area behind the generator into the gen compartment. On our trailer the line was pinched at the wall separating the gen from the basement.

My thoughts - you have no choice but to inspect the entire fuel line, dropping the corroplast on the left side.

But, since your rig is a 2008 and you have had no choice but to use ethanol fuel in the last 10 years, the odds are in your favor that the fuel line has been comprised by the use of ethanol laced fuel.

If you are going to go through the trouble of dropping the corroplast to inspect - just replace it.

Replacing it may even be easier. You may be able to pull the line from the back to the front with only dropping the corroplast in the basement area.
The corroplast stops at the rear axles and the fuel line is visible from there to where it goes up tot the top of the tank.

Porthole, you advise dropping the coro-last on the left side; is that the door side or slide out side?

 

[porthole]

Porthole, you advise dropping the coro-last on the left side; is that the door side or slide out side?

"slide out side"


In the automotive world, left and right is designated as if you are behind the steering wheel, facing forward.
In the RV world left and right is designated as the "off door side" (left) or "door side" (right).

So, I should have said the ODS, off door side.

And, expect some of those self tappers to break when you remove them. Get new screws before you start, don't bother trying to remove any of the broken ones, just use a new one next to it.

 

[MrBill]

Thank you Porthole!

 

[MrBill]

fuel line leak was just a few few behind the generator where it goes down through the frame. New hose in place, generator runs great again. Thanks for those who submitted advice.