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deprived · 01-21-2022, 06:32 PM

I had to remove all of the old diesel out of my fuel tank today. The easiest way was one of those drill-powered pumps through my generator fuel line. It went fairly quickly.

But now this little inline filter is all gooped up and I need to replace it.

My question: Will any inline fuel filter work or does it have to be diesel-specific?

Could I use something like this? https://www.amazon.com/FRAM-G12-in-L..._t2_B002IAX5BG

Bear in mind that I am not referring to the box-shaped filter in the genset itself but rather the plastic inline filter.

Interesting note: I had always thought that the generator wasn't supposed to be able to use up all of the fuel in the tank, that it was designed to leave about 1/4 of the tank alone. However, I managed to suck out all of the fuel because now the fuel gauge reads 100% empty. I don't know if this is some kind of error in how the generator feed line was installed in the fuel tank or if this is how it's supposed to work. Something to think about, anyway..

96 Wideglide · 01-21-2022, 06:43 PM

Your generator fuel line is only going to reach somewhere about 2/3 to 3/4 of your fuel tank.

*edit* sorry, didn't read your red note.

bigb56 · 01-21-2022, 06:45 PM

I don't see why not, when I had a Mercedes 300 it took those little plastic VW Beetle filters for my inline primary and in those days VW Beetles were all gasoline, they worked great.
If it can't be used with diesel they would probably call it a gasoline filter.

As far as the fuel level, even though the gauge reads empty I'll bet there is still a fair amount left.

BobGed · 01-21-2022, 06:54 PM

Tiffin hasn't been installing the inline generator filter for many years. I didn't have one on my 2009 Phaeton and don't have one on my current coach.

Personally I would just run a straight line without that filter.

sandwip · 01-21-2022, 08:15 PM

If the OP managed to plug up that little filter, do you not think eliminating it would destroy the genset fuel system in short order. I believe the small filter should work, and I would get 2 and have 1 for a spare.

Dutch Star Don · 01-21-2022, 08:32 PM

First off, even though your gauge says empty, it doesn't mean that it's accurate. I know when I owned my 2005 Diplomat, many were pulling the generator pickup and lengthening it. Maybe a PO did the same.

I agree with BobGed, if your Onan has the fuel filter inside the trap door, (OEM) you really don't need a second one.

bigb56 · 01-22-2022, 08:17 AM

A primary filter may not be necessary but it does help to keep large crap out of the main filter, and allows a visual check of fuel supply which can save a lot of time and headaches when troubleshooting fuel delivery issues. A nice addition instead of a filter is a clear bowl with a debris screen and water separator.

ArtJoyce · 01-22-2022, 08:26 AM

I would get a diesel filters. There should be plenty available. VW had that diesel rabbit in 1979 and after that they almost alway had at least one diesel in the product line.