Generator fuel tank problems

[Wizard46]

Finally got my generator running. Replaced fuel pump/filter, would start and run for a few minutes. After priming for several minutes the same would happen. figured it was starving for fuel. Fuel line was hard as a rock and I think the pump was starving for fuel, maybe sucking air. Several joints in line as a in-line filter was added in the past. Clamps at original onan fuel filter, two clamps on in-line filter and whatever in on fuel tank. I replaced the fuel line and in-line filter and new clamps. Could not get to fuel tank fitting so I cut fuel line about a foot from tank and made a splice with brass coupling and clamps.
Now after priming it will start and run about forever sitting in my yard. Drive down the road and it shuts down. Back home and after a long prime, several minutes same thing, starts and runs.
My question, has anybody ever dropped gas tank, or had it done. That may be above my pay grade. I think the gas line may be bad where it connects to the tank.

 

[DonTom]

Drive down the road and it shuts down.

-Don- Reno, NV

 

[Ex-Calif]

Don't get caught thinking you are chasing the same problem. My generator would start from cold and run forever. However if shut down it would not relight until it cooled.

I diagnosed it as rich mixture and after leaning it out it would hot restart.

Also make sure the choke (if auto choke fitted) is not gummed up/frozen/binding.

If yours is auto shutting "while" driving then that's a bit of a conundrum but could have something to do with airflow while driving impacting things. Or more ominous is something in the fuel tank that is porting and unporting while moving.

Another long shot is fuel bowl height being low or a bad needle and seat on the carb that is moving around - not likely however as the natural vibration of the generator should expose that one.

Anyway, that's my brainstorming contribution.

 

[Kirk]

My question, has anybody ever dropped gas tank, or had it done.

I have but for a different reason. I had a fuel pump issue with my F53 chassis about 15 years ago or so. The shop dropped the tank to replace the fuel pump and in process twisted off several of the mounting bolts so the pump flange came loose in about a month and I ran gas over the top of the tank. I took it to a different Ford truck shop and had the tank dropped again. They sent pictures of it to the shop that did the origional work and that shop paid for a new tank and all labor.

 

[Wizard46]

Forgot to mention that it's a Class C, Coachman on E350 chassis

 

[jubileee]

I’ve seen pin holes in gen fuel line right the fuel tank two or thee times. On the old Bounder, I was able to slip a pair of hose shut off pliers in between frame rail and tank, pinch off fuel line, and pull vacuum on line to find leak. Just lowered tank a little to repair.
Another intermittent problem along the line of yours, is a failing low oil sensor. Jounce unit around and it’ll kill engine. May even keep it from starting for a while.
I heard Onan quit installing low oil shut offs on new units. I unplug every one I come across and tell people to check the oil.