Onan Generator pump replacement DIY... error code 17

[Redridge]

Generator Fuel Pump Replacement DIY… error code 17

Toward the last days of our trip (on the way home), we’ve been getting intermittent error code 17. So when we got home, I ordered from Onan a new fuel pump, oil, air and fuel filter. Thought it was easy enough to do…. the failed fuel pump did not match the new pump Onan sent so it looks like there is an updated pump...

Underneath the generator is this panel, beneath it is the fuel pump. Just pinch the two plastic tabs and the panel will come out.



The fuel pump is located on the left (the fuel filter is at the very top of the picture). This side is the outlet going into the fuel filter. Disconnect the electrical wires. The connections are keyed, but yours' may not be… so take note.



This is the other side of the generator… the hose on the right is the inlet fuel line going to the fuel pump. The left side is the return fuel line. You want to unhook the (right hose) inlet side of the pump and plug the hose (I used golf tees) so you won’t have fuel everywhere. Remove the elbow mounted to the pump so you can take the pump out easier.



Unscrew the outlet fuel hose of the pump and screw it to the new fuel pump (plug the other side of the new fuel pump with golf Tees) so you wont have fuel leaking everywhere….

To unmount the bad fuel pump is the dilemma. There is a support (bar can be seen in the first pic) bar that covers the mounting screws of the pump. To get at the mounting screws, you have to support the generator and move the bar out of the way. Removing the bar, you have to remove the 2 mounting screws to the generator and 2 screws to a frame of the chassis.

here, the generator is supported by a jack and a 2x4 that runs the length of the generator… with the support bar out of the way, you see the 2 exposed mounting screws of the fuel pump.



You can move the bar out of the way to get to the covered screws, but I took it a step further and notched the bar to have easy access to the 2 fuel pump mounting screws. Remove the bad pump and connect the new fuel pump inlet lines.



the tool used to notch the bar…



and the finished result… Thor need to do this at the factory.



Make sure all mounting screws are in place and test the generator with half load on it.... mine worked perfect.

I also bought a spare pump from Amazon… a much cheaper alternative. The Amazon pump is on the bottom and looks identical to the older bad fuel pump.

Amazon.com: Airtex E11020 Electric Fuel Pump for Onan Generator Set: Automotive

[Don Voyage]

Ferdinand,
Thanks so much for sharing this pump replacement procedure along with pictures.

I have a few questions:

1- How many hours were on the generator when you starting having problems?

2- Was the cross support removed part of the generator or added on by Thor?

3- It looks like the mounting of the pump required nuts on the inside of generator compartment, how were you able to access the left side of pump for the nut?

4-The picture of the pumps side by side, is the one with the "E11020" in the front, the new or old pump from Onan?

5- What was the signs you were having a problem?

Great job and Thanks again!
Don

[Redridge]

Your welcome Don,

1- How many hours were on the generator when you starting having problems?

I have 175 hours now... started showing intermittent problems around 160 hours and around 165 hours was shutting down after 1-3 hours. This was during some very hot days in Tx and NM

2- Was the cross support removed part of the generator or added on by Thor?

the cross support looks like it was Thors' doing. I dont think they know they covered the pumps screw access.

3- It looks like the mounting of the pump required nuts on the inside of generator compartment, how were you able to access the left side of pump for the nut?

On top of the fuel pump is some sort of heat shield or cover (you can see it on Pic #2)... it has a built in nut for the two screws to clamp down the pump. The screws access are located under the frame of the generator... which Thor covered up by the cross support. Hence, me notching the cross support to access the 2 screws.

4-The picture of the pumps side by side, is the one with the "E11020" in the front, the new or old pump from Onan?

I bought 2 pumps, one from Onan and one from Amazon... here are the part#'s

Onan Failed pump 149-2790
New Onan pump A047N931 - $90
Amazon Airtex Pump E11020 - $40 see above link.

The pump marked E11020 is an Airtex pump from Amazon... It looks like Onan just rebranded it to charge the extra $$$.

5- What was the signs you were having a problem?

The very first signs were when you press the start button, you initially hear the clicking (priming) sound of the pump... then it silences and throws a code 17. As long as it keeps priming it will start... if you dont hear the click, the pump will fail. Then it progressively gets worse after that. Wont start till 2-3 days later (but works the whole day)... then, if it starts, it will only work 1-3 hours, then it wont start at all... making it unrealiable.

[tbbg II]

I wish you were my neighbor!

[CJ7365]

Great write up Red Ridge, Did you email Thor about the GREAT mod you made to their bracket, and as with all vehicles the engineers probably don't even consider access to replace parts etc....


With 175 hours on the gen set, that was a very expensive onan fuel pump, any way of getting some warranty on the original part.


I also replaced my pump with the Air tex brand pump, got 100 hrs on it so far.

[Redridge]

I was def dissapointed with the pump failure... but after researching the net, there is a lot of failure with these pumps. I did not email Thor... apparently they read these boards, and they sponsor it.

The reason why I didnt bother with Thor was self reliance. I did call Onan and they said it was out of warranty. I believe Onan were installing the Airtex 11016 which was failing and upgraded it to the 11020... just my guess.

Imagine, Onan installing a new pump not knowing new/old part #'s or replacement.... at least, for $90 and additional $40, I have the know how and a cheaper alternative equal pump as a spare. Plus, I cant see Onan notching that support bar for the screw access, they would of just put the old bar back up there... a pump field swap is a lot easier now.

[Don Voyage]

Ferdinand,

I think I will measure off approx measurement and use a hole saw to gain access to these mounting bolts if needed on the road. Also, ordered an extra Airtex E11020 pump for back-up if needed from Amazon.

Just recently received a new fuel filter and air filter too for general maintenance. I have @ 348 hours on my generator so far with no problems. I only use Rotella T-6, 5W-40 synthedic in both engine and generator.

Sending you a PM on your recent trip to TX and NM.

Thanks!
Don

[Ray,IN]

Onan 7.5kw; 1,886 hrs. and counting, with no problems whatsoever.

[Peterrrr]

Great write up Ferdinand. I hope I never have to reference it in the future, but if I do it certainly will make the job easier. Thanks again for a job well done.

[PWAmbs]

I just have my pump replaced this week, extended warranted covered it. Had 120 hours on Genny. No symptoms except quite. the repair facility is charging over $800 to the EXT, I paid $50. Onan pump A047Z224 $91.19, Fuel filter 147-0860 $15.29, lots of labor at @130/hr.

2013 Palazzo. 33.2

[Redridge]

wow... $800, thats robbery. Hopefully this DIY will help a few folks out, especially at $40 replacement pump.

[RKNOLA]

We had the dreaded "code 17" last year. Contacted Thor, they said contact Cummins. Pump replaced by Cummins repair facility. No charge to us.