450: Aftermarket fuel pump for Onan generator

[Millerslocal]

Hi

Has anyone replaced the fuel pump on the Onan generator with an aftermarket one? Genuine Cummins/Onan fuel pump is (a) expensive and (b) hard to source locally.

I have read that Airtex are the actual Onan pump manufacturers - but same issue - can only import and none available locally.

Would any low pressure in-line automotive fuel pump work? And what would the required psi rating be? Is there anything else specific in the Onan/Airtex pump that I need to ensure is part of the specs of a generic replacement pump?

Current model is Onan 149-2646 ( can be replaced by Airtex E11016)

Thanks in advance!

[Bean Counter]

On our 2011 L450 there are two fuel pumps for the generator. One on the engine and one behind the fuel water separator, under where the ON OFF battery switches are.
I think they run two because the standard Onan pump will only lift 4 ft.

Any way the one on the engine failed and started leaking. We were in the Bahamas so I bought a Facet model 574A from NAPA autoparts, I think it has a bit more pressure, but it ran fine for six months till we got back to the USA and bought an Onan replacement. I keep the facet as a spare as I think it will also do for the Yanmar engines in an emergency.

[Millerslocal]

Thanks Bean Counter.

Apparently 574A is not a part number but a Listing number that appears on all Facet fuel pumps. The Facet part number is a 5- to 7-digit stamped on the mounting flange - any chance of checking that for me.

Googling the specs of the Onan/Airtex fuel pumps they indicate 8-9psi. Had thought the pump should be only 3-4psi to prevent flooding of the carb?

Thanks

[Bean Counter]

Stamped on the Facet flange is 40107. It is 10 - 7 Psi, wet lift 12". As it only needs to lift the output from the first pump, it is ok. Maybe a single pump with a 84" lift would be better as the tank is probably 6 ft below the generator
Cube Fuel-Pumps | Motor Components, LLC | Facet Purolator

There is no carburetor it is fuel injected so injector pump provides the real fuel pressure.

[Millerslocal]

Thanks Bean Counter - that is the Facet pump I thought it would be based on the psi/output of the existing pump - so great to have that confirmed. Much appreciated.

Cost of this is half the price of the Onan replacement, and Facet pumps seem to have an acceptable name, not some Chinese rip-off, so hoping it will turn out to be a good option. How long have your Facet installed for?

[sailcrazy]

Our 6.5kva diesel-powered Onan genset fuel pump quit last season, and there was no Onan parts supplier anywhere around. I went to the local Napa store, bought the larger of their 2 over-the-counter 12vDC electric fuel pumps, and installed it......it worked perfectly. I have since replaced it with the genuine Onan part-at 250% the cost and have the Napa pump in my spares locker. But the Napa unit worked flawlessly and we run our genset everyday, 2x each day when we're onboard!

[sailcrazy]

PS....I wasn't sure the small fuel filter Napa supplied would work OK with diesel (vs gas), but I put it inline and it worked just fine!

[herbert.dietz]

Originally Posted by Millerslocal

Hi

Has anyone replaced the fuel pump on the Onan generator with an aftermarket one? Genuine Cummins/Onan fuel pump is (a) expensive and (b) hard to source locally.

I have read that Airtex are the actual Onan pump manufacturers - but same issue - can only import and none available locally.

Would any low pressure in-line automotive fuel pump work? And what would the required psi rating be? Is there anything else specific in the Onan/Airtex pump that I need to ensure is part of the specs of a generic replacement pump?

Current model is Onan 149-2646 ( can be replaced by Airtex E11016)

Thanks in advance!

On my L52 The prepump on the 17.5kw onan also brake down -elektrikal Problem.Genarator did not start.
when you take the two 12V Cable from the pump away the genarator will work without any Problem . In our boat about 2 month until we get sparepart. you can take every low pressour 12 V prepump.

[Millerslocal]

Thanks again for all the feedback. Installed a Facet fuel pump (Part no. 40107) with specs 7-10 psi and delivery of 30gph. Have a happy generator again. SO provided is a pump with same specs as the original (6-9 psi and 34gph) it is fine. Form factor not an issue.