Hello everyone...love to hear your feedback. I have a Georgie boy Landau 2005 with a 5500 onan generator. The generator was having problems starting so I took the RV to a repair shop and one test they ran was spraying carburetor or fuel cleaner into the front of the carb which allowed it to run for a few seconds. They diagnosed it as a bad carburetor. So $600 later they replace the carburetor and still the generator will not start. While trying to prime the generator you can hear it click but no fuel was coming out. So I left there they told me I need to go see an onan certified generator repair shop, at home this morning I just on a whim tried it and the fuel pump will prime...I can hear it and see the hose filling. So I shut it off to try it again and the same problem there’s a click and no priming. Anybody ever had this before? Thanks for your time!

The most common problem with a 10 year or older Motorhome, is, the rubber fuel line from the Fuel tank pick up tube to the Genset has dry rotted. The small cracks cause air thru the rubber and that disables the fuel pump from getting its prime to pull fuel. A quick way to determine this is to connect a gallon gas can and remove the existing fuel line from the genset and connecting a good new rubber line and see if the Fuel pump then primes. Usually it will. DougPS, If you hear a click, that may be the fuel cut off solenoid opening. BUT, you should also hear the Fuel Pump rattling trying to pump. This would mean your above fuel line is good. Also, I believe the fuel pump has a pressure cut off. When the fuel pump cannot pump, its internal pressure switch shuts off. When testing the fuel prime you need to disconnect the metal line at the Carb input. Onan and other Genset makers require a LOW pressure fuel pump which is what Onan makes and supplies. The aftermarket Automotive similar looking pumps are 2 to 3 times the PSI of a genset pump.

Thanks Doug...so the prime seems to be intermittent. It was just running for about 5Minutes then stops. After it stops all I hear when I go to prime is a click...no fuelMoving. If I wait about 10 minutes it’ll prime and start again, run for about 5 min then shut off. My fuel tank is between 1/4 and 1/2.

Rsnawder wrote:Thanks Doug...so the prime seems to be intermittent. It was just running for about 5Minutes then stops. After it stops all I hear when I go to prime is a click...no fuelMoving. If I wait about 10 minutes it’ll prime and start again, run for about 5 min then shut off. My fuel tank is between 1/4 and 1/2.Get the fuel tank above 1/2 tank and retest. Your 1/4 tank pick up may not be accurate. Doug

Will do..then I’ll report back. Thank you

Filled to 3/4 tank, same results. I’m going to try 2 things:1). Charge all batteries to fill then try again2). Leave the gas cap off. It’s a stretch...any other suggestions?Thanks!

Onan 5500 fuel pump not priming | Good Sam Community

msmith1_wa
Explorer
Aug 19, 2019
Change the fuel filter
Rsnawder
Explorer
Aug 19, 2019
UPDATE:
So I disconnected the line going from the fuel pump to the fuel tank, bought and screwed in a new fuel filter, connected a fuel line from there to a portable 5 gallon fuel jug, went to prime and all I get is a click...no suck. Is this a fuel pump problem potentially as well?
Rsnawder
Explorer
Aug 19, 2019
.
Rsnawder
Explorer
Aug 19, 2019
The priming pump seems to be intermittent. It was working, pulled a prime from my fuel jug, it’ll run for a few seconds...sometimes 30 seconds at most, then shuts off. I keep getting the 37 code and once i got a 15 code.
bounder39zman
Explorer II
Aug 19, 2019
sounds like you need a pump. ONAN p/n A047N929.
is easy to change. All posts about aging fuel lines are possible;
but it acts like the pump quits pumping when it warms up....very common problem. See it frequently, fuel pumps are my most sold part.
are you getting a fault code when shuts off? should be a "36" but other codes possible.
dougrainer
Nomad
Aug 20, 2019
wa8yxm wrote:
YOu say it primes and runs. then it stops and won't prime. then it primes and runs, then it stops and won't prime.

The fuel pickup in the tank has a strainer (pre-strainer) just like the water pump has. If you've left old gas in the tank (Gasser) or algae has grown (Diesel) that pre-strainer may be clogged.

Then there is the fuel filter it too can clog

And a pinched fuel line not letting fuel through.

all of those will act exactly as you have described Error code will show "No fuel".

A Genset fuel pick up in the fuel tank is just a straight metal tube that is terminates right at the 1/4 tank level of the fuel tank. NO filter or strainer at all. Diesel and Gas are the same. Doug
bobsallyh
Explorer II
Aug 20, 2019
rsnawder, if you decide to change your fuel pump, Google- Airtex E11015. It is the same pump that Cummins/Onan wants big bucks for.
full-timer
Explorer
Aug 21, 2019
I was having the same problem with my 5500W Onan.
I bought the above Airtex E1105 fuel pump from Amazon and installed it, no more problems. It keeps running until I shut it down.
rentman99
Explorer
Aug 21, 2019
How old is the fuel pump? Sounds like it may be a bit flaky. An old electric pump can get unreliable after it warms up. When it cools, it starts pumping again.

I wouldn't hesitate at all in replacing a 15 year old fuel pump. You can always keep it as a spare if the problem turns out to be something else. At least you'll be traveling with a new fuel pump.

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Onan 5500 fuel pump not priming

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