Onan Generator question

[Rick Flores]

I have a Marquis Gold 5.5 carborated Onan. Every month I turn it on if it isn't being used and let it run for an hour. This time after it started it quit running. The code comes up: 4 & 36, no gas, but my tank had 1/2 tank. Would not prime, disconnected gas line from back of pump, got 2 gal can of gas, added fuel hose from gas can to back side of pump. Engaged start switch & it ran for 45 min. I hit stop, disconnected gas can from fuel line from back of pump, reconnected fuel line from mtr home gas tank to pump. Before that blew compressor air thru fuel line to tank, blew gas out thru filler neck all clear. Restarted generator, ran for a few minutes and ran out of gas again, still will not prime. Prime doesn't make that clicking sound when pressing start like it should. The carburetor was replaced about a year ago, could it be the fuel pump? Has anyone had this problem with startup? Mtr home generator fuel line and carb bowl both dry again..stumped! Was thinking of using a electric faucet fuel pump attached to gas line to tank to see if it pulls gas...your ideas & thoughts please

[TandW]

Go fill your Gas Tank, topping it off. Run generator. If it now continues to run you have a hole in your generator fuel pick up tube or it has fallen away inside the tank. Good Luck!!

[Rick Flores]

Thank you...I'll give it a try...will keep you posted

[Easyrider]

Tandw has a good idea, another reason if it continues to run would be your gas gauge isn't accurate and you have less gas than it indicates. But you should be able to tell that by how much gas you put in.

[LVJ58]

Rick, if it still gives you problems after you top off your tank, I would check for a crack or split in the fuel line between the pump and your fuel tank.

I had a problem similar to yours with our Onan 5.5 and a break in the rubber line where it was connected to the fuel tank was causing the pump to suck air and no fuel.

Best of luck, Jim

[Gary RVRoamer]

I'd bet on a laaky fuel line, sucking air instead of gas. The air leaks can be extremely hard to see/detect.

[nbounder]

I'd hope it's not a cracked line at the top of the fuel tank. I just had my fuel pump replaced on my 95 Bounder - they needed to drop the tank. After I paid the bill, the svc mgr bought a new Mercedes. I got the better deal, though - my vehicle has a potty & a bedroom - HIS DON'T!!

[justimagination]

got 2 gal can of gas, added fuel hose from gas can to back side of pump. Engaged start switch & it ran for 45 min. I hit stop,

I believe you answered your question. As other's have said, I too believe you have a bad gas line from your tank to the Generator. Good Luck,
David G.

[leadman]

If you have a hand held vacumn pump with the brake bleeder attachment you can hook this up to the generator to fuel tank line and do a test.
If when pumping the vac pump handle either no gas is drawn into the container or you can't build any vacumn then you have a hole in the line or a problem with the pick up in the tank.

If you have no vacumn or no gas at the generator then go to the tank and perform the test again. This will test the pick up in the tank. no vacumn or no gas, will probably have to pull the tank if the pick up can't be accessed.