Okay, I feel like an idiot. When replacing the fuel filter cap, how do you keep the o-ring from popping out? It seems awfully loose so I can understand why it would pop out, but is there something I'm missing?

 

If its like mine, it fits in the groove on the cap nice and snug.

 

Thanks for the reply. I couldn't find a groove in the cap but it fits very loosely around the threads. Could almost go around the outside of the canister as a decoration. I'll go check to see if I can find a groove.

 

I found the groove in the cap just above the threads that the o-ring sits in but there was nothing nice and snug about it. Anyway, after tightening it, it popped out again and then ripped. Since the one parts store in town that's open today didn't have an o-ring larger than 3.5" diameter, I went to Ace Hardware who had a 4" which is a quarter inch too small but definitely fits nice and snug. It's also a just a little thicker but does the trick. Problem solved.

 

Don't know if the o-ring that comes with the filter is special in any sort of way because it's in contact with fuel, but it would be a shame if fuel attacked that Ace Hardware 0-ring and let that stuff get in the injection system.

Maybe somebody here knows. All I know is there's a bunch of different materials that o-rings are made of, such as Buna and Viton.

 

Glad you solved the problem. It shouldn't be a difficult evolution. CP raised a good question, and one that I'm not sure of the answer - other than diesel fuel can be a PIA to some rubber materials.

Were you replacing a fuel filter or just "checking" the old one. If replacing, did the new filter come with an O-ring? Or did you reuse the old one? In any event, I've never had the old one be loose and floppy like that.

BTW, what was the brand of filter? Never had any issues with Fleetguards.

Might be worthwhile to stop by a NAPA or Cummins Power Store and pick up a new O-ring.

 

Yeah, I thought about the fuel breaking down the rubber if it wasn't the right material but has the same look and feel as the old one. It was the filter from the factory on there and I was just checking it as I've recently noticed a slight drop in the operating fuel pressure. It's down to around 5psi so I'm guessing that it's soon time to change the filter. I'm deploying tomorrow and by the time I get back it will be just about time to change the filter anyway. I told the wife while I'm gone that if she wants to take the trailer and go camping to take the truck to the diesel place a few exits south of here along I-5 to get the filter changed first.

 

Just an FYI for the future. You can't reuse the oring because it stretches. If your going to check your filter replace it with a new one and the new oring that comes with it.

 

Not much help now, but I save an old one in case I mess up a new down the line.

Pete

 

I had this problem when my rig was new, turned out that i left the old o ring in there

Sounds crazy, but check to make sure you didn't accidently leave an old o ring in there.

 

the way the filter is located, any rubber getting into the canister will get caught by the filter element. the fuel outlet is the center inside the filter