Forum Discussion

Explorer

Jun 01, 2013

Location of Onan 7500 fuel filter

Our 2004 Fleetwood Discovery has an Onan 7500 quiet diesel generator that worked great when we parked it in late March. Now it runs quits after running 30 minutes with both roof airs on. I replaced the air filter which helped increase the run time from 15 minutes to the present 30 minutes. I restarted it and turned the two AC units off and it has been running now for about 45 minutes, but there is no load on it (no roof airs are on). It continues to run, but is "cycling" from fast to slower speed at a regular rate.
I think I need to replace the fuel filter, but I can not find it!
Can anyone tell me where the fuel filter is?
The air filter was accessible from under the generator. I have no clue where to look for the fuel filter. Can't find any help in the online manuals I've found.
Thanks in advance for pointing us in the right direction. We leave Monday to drive across New Mexico and Arizona and I do not look forward to travelling without air!
Thanks,
Sally

Class A

13 Replies

dougrainer
Nomad
Jun 01, 2013
You can replace the fuel filter, but I doubt that is your problem. When it dies, does it start right back up? If so, then the fuel filter is not the problem. Fuel Filters on RV APU's rarely get clogged as the pick up tube for the fuel is located no lower than the 1/4 tank level in the fuel tank and debris in fuel rarely stays in suspension in a fuel tank for the APU to pick up trash. The Fuel filter is located BELOW the Oil Filter. Doug
Big_Katuna
Explorer II
Jun 01, 2013
If you have to ask, you probably shouldn't be changing it. Its behind a door on the bottom of the genset where the oil filter is too. Silver box. Has metal supply lines that require line wrenches to undo or you risk ruining the fittings. You can buy replacement filters at NAPA.
Doesn't sound like you have been doing your maintenance regularly.
Trackrig
Explorer II
Jun 01, 2013
The You Tube video shows where it's at, but they don't say how to change it. It's about 20 - 25% of the way into the video.

Clicky showing where fuel filter is.

Hope that helps.

Bill