Onan 5500 No Gas in Winnebao Adventurer

hanko wrote:

cochise49 wrote:
If the genset had been sitting for a long time, the old fuel can varnish the carb bowl and cause symptoms like that. Read an article in the latest FMCA magazine today about it online. Haven't gotten that issue in the mail yet. The author had to replace the carb in that case. I know generators like to be used.

man did you read what he said???? if he sucks gas from a remote can it runs like a champ.

I guess not. No need as long as there are other, more thorough readers to point it out to me. Thanks.

Some rigs had a generic filter cut into the steel line.
Might check your local auto parts store for steel lines. They will be straight and need to be bent.

Fixed!!! Hopefully for good!

I bi-passed the steel section of line with a section of flexible rubber hose and it works.

Going to try and track down the rigid section part number and eventually replace it, but for now the flexible will keep us rolling!

Is the vent on your fuel tank plugged? Some gas caps are vented and if the vent is clogged, the generator fuel pump may not be strong enough to overcome the vacuum. An indication of this is that the generator will run for less time when your main fuel tank is full and will run longer when the fuel level is lower in the tank. Just take the fuel fill cap off and see how the generator runs.

After reading all of the posts, my first thoughts are that the fuel pump is picking up air somewhere. Check your clamps good everywhere there is a connection or joint. Make sure there is not a crack or a crimp in your solid line and that the joint is solid where it meets the rubber line.

swreeder70 wrote:
The only fuel line that hasn't been replaced is a section of rigid tubing.

This past spring I had the dealer drop the tank and replace the first section of flexible gas line. Of course it worked fine leaving the dealer, but failed two weeks later, but then magically started working and had worked well all summer.

Today I replace the back section of flex line with no luck. I also shot air into the tank through the line and that didn't make a difference.

I'm thinking it is one of three things.
1. The section of steel tubing is bad
2. There is something wrong with the pickup inside the tank.
3. There is some kind of mechanical cutoff for the fuel when the tank gets below 1/4 that is failing.

The part of mine that was bad was the steel line,I said crack in my post but actually it was rust.If you can find the bad place ,you should be able to cut it out and slide the rubber line over the two ends and clamp them.

I don't think there is anything mechanical for a shutoff, the pickup is just located higher in the tank than the one for the engine to prevent one from running tank dry using generator

The only fuel line that hasn't been replaced is a section of rigid tubing.

This past spring I had the dealer drop the tank and replace the first section of flexible gas line. Of course it worked fine leaving the dealer, but failed two weeks later, but then magically started working and had worked well all summer.

Today I replace the back section of flex line with no luck. I also shot air into the tank through the line and that didn't make a difference.

I'm thinking it is one of three things.
1. The section of steel tubing is bad
2. There is something wrong with the pickup inside the tank.
3. There is some kind of mechanical cutoff for the fuel when the tank gets below 1/4 that is failing.

cochise49 wrote:
If the genset had been sitting for a long time, the old fuel can varnish the carb bowl and cause symptoms like that. Read an article in the latest FMCA magazine today about it online. Haven't gotten that issue in the mail yet. The author had to replace the carb in that case. I know generators like to be used.

man did you read what he said???? if he sucks gas from a remote can it runs like a champ.

I had same problem on my coach, sometime the generator would run good other times not.

Long story short,The fuel supply line coming from tank had a crack in it and would cause the fuel pump on generator to "lose its prime"by allowing air in line.

You mentioned the unit would run fine while pulling gas from another source so it has to be one of two things, a hole in fuel line or something wrong with gas pickup in tank.

I missed about it running ok with auxiliary tank. Yes, try blowing back into the main tank. Disconnect before the filter and fuel pump on genset. Locate the line as it comes from the tank.