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Onan RV Generator Maintenance: Replacing The Fuel Filter

Onan RV Generator Maintenance: Replacing The Fuel Filter

Our RV just turned 10! We took delivery on May 17, 2005, so its birthday present was a new generator fuel filter.

Three years ago, our first two Onan generator maintenance videos showed how to change the oil & oil filter, clean the spark arrestor, replace the air filter, flush the cooling system and replace the anti-freeze. Since then we’ve received multiple requests to show the fuel filter replacement.

Having solar panels and being frugal with power, we tend to keep the hours on our generator to a minimum. The fuel filter only gets replaced every 500 hours, so we haven’t had to do it since prior to making our very first YouTube video, nearly four years ago. Finally, here it is!

We’ve seen quite a bit of discussion about this being a tricky job, but it’s actually a breeze. If we weren’t videoing it, we could easily complete the job in about 15 minutes (shooting video seems to make any project take about 5 times longer). ;-)

We have an Onan 7.5 kilowatt QuietDiesel generator. If you have a different model, be sure to check your owner’s manual for possible differences in the procedure.


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Richard Davis

Saturday 15th of June 2019

These videos have saved me so much. The plastic latch on my Onan generator, just like the one in the picture, has broken. Any idea on the part# or where I can get a replacement? Thanks

TheRVgeeks

Saturday 15th of June 2019

Hi Richard. It's always nice to hear we've been helpful. We THINK this is the latch for the access door on OUR generator for the fuel and oil filters - Onan part #406−0612 which we found here: https://www.rvpartscountry.com/Service-Panel-Latch-for-Onan-Generators_p_34087.html If yours is a different model generator, you can start by visiting the Onan Parts page, clicking Power Generation, and entering your serial number. Everything should flow from there! Hope this helps. https://parts.cummins.com/?_ga=2.166163390.183289350.1560648306-1606850432.1560648306#/

Highwayman

Sunday 1st of July 2018

I have the exact same generator in my 2000 Discovery, Serviced the complete system, oil / filter and diesel filter. The generator would not start prior and it still won't with it flashing 3 times on the switch which I read it means it 'needs service'. Question, is that an additional filter in line to the right in your video (and on my generator) the copper colored one that looks an inline filter round and a couple inches long?

TheRVgeeks

Monday 2nd of July 2018

Hi Richard. We don't believe there is any additional fuel filter. The one we showed being replaced in this video is the only one. About the code you're seeing... there should be two codes, not just one - a first stage code, followed by a second stage code. If you look in the manual, you'll see directions for how to get the second digit (second set of flashes) that you need. Three flashes is only the first stage, so you need the second stage number to hone in on the problem in more detail.

Jimmy

Wednesday 18th of October 2017

I have a 1998 Georgetown motorhome and a cant get gas to the gen. will not come out of the gas line. where is the fuel filter locateed

TheRVgeeks

Wednesday 18th of October 2017

Hi Jimmy! Unfortunately we don't have a gas rig, so we only have experience with a diesel generator. That said, there is one thing that's probably the same on both types of rigs, and the first thing we would check: the fuel level. Since they don't want someone to accidentally use up so much fuel by running the generator that the tank runs dry, the fuel pick-up for the generator is usually located higher on the tank. So you can only run the generator down to about 1/4 tank or so, before the gas level falls below the generator pick-up line. So the very first thing to do is make sure you have enough fuel in the tank to be above the generator pick-up line (if you have half a tank of gas or more, then that certainly can't be the problem. If that's not it, we'd suggest checking out the website of our good friend Brian of RV With Tito (www.rvwithtito.com). He has a Class C gas motorhome with an Onan gas generator. We just checked, and he has a video about troubleshooting the generator fuel pump that might have some useful information for you. That video is here. If that video doesn't help, he may have other related videos that do. Barring that, Brian is a very handy DIY RVer, who would be happy to try to help if you contact him through his website. Tell him the RVgeeks sent you, and said Hi!

Kathleen Oliver

Monday 12th of September 2016

I have a used 2003 Forest River Sierra Sport toy-hauler with the Onan Micro-Quiet 4000 gas generator. It is bolted to the frame of the trailer on the driver's side. According to the owner's manual the fuel filter is on the left lower side when looking at the generator. It looks to me the entire generator has to be removed from the compartment to access the fuel filter. Is there an easier way to get to this filter? Thoughts, ideas, suggestions would be appreciated.

TheRVgeeks

Monday 12th of September 2016

Hi Kathleen. We're not familiar with the MicroQuiet series, but we just found this link on RV.net that should be of help: http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/23176033/gotomsg/23176979.cfm#23176979

Please let us know how you make out.

Jay McGillicuddy

Tuesday 19th of July 2016

Another great video. How many quarts of oil do you use? I have the same generator. I guess I should open the manual.

I am surprised the fuel filer can go 500 hours before changing good to know.

TheRVgeeks

Tuesday 19th of July 2016

Thanks Jay! The oil capacity is listed as 3 quarts, but I recall that it seems to take a little more or a little less than that (I can never remember which until I do it each year). ;-)

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