Onan 5500 fuel pump not priming

[Rsnawder]

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!

[rentman99]

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.

[full-timer]

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.

[bobsallyh]

rsnawder, if you decide to change your fuel pump, Google- Airtex E11015. It is the same pump that Cummins/Onan wants big bucks for.

[dougrainer]

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

[bounder39zman]

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.

[Rsnawder]

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.

[Rsnawder]

.

[Rsnawder]

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?

[msmith1_wa]

Change the fuel filter

[Rsnawder]

Awesome! Thank you everyone. I will start with the fuel line to a gas can and roll from there. I’ll update. Thanks again!

[turbojimmy]

I had a similar problem with my '84. Fuel pump would prime, generator would run for a while, fuel pump would start to clatter (as it ran out of fuel). Run times varied - it was frustrating.

Turns out it was a loose hose clamp at the fuel pickup at the tank. A dry rotted line would behave the same way.

Disconnect the fuel line and run it right from a gas can. If it runs without any trouble, there's your answer.

[wa8yxm]

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".

[Matt_Colie]

Rsnawder,

I know you may not think it is old, but 15 years (yours is supposed to be 14) is about the life of a fuel line these days. Make sure it is replaced with something alcohol compatible.

Matt

[dougrainer]

Gas Gensets use about .7 gallons per hour. Connect a 1 gallon Gas can to the Gas input of the Genset and run the Genset. If it fails, then you need a new fuel pump. IF it stays running then think about a rotted supply line from the fuel tank. Doug