Fuel filter O rings

[M&EM]

Replaced fuel filter(3rd time) 65k miles. This time I noticed an O ring was present on the outlet side fuel line but not on the inlet side. Apparently this O ring has been lost or was never there. Seems that the compression flange seals well without it. I have not had any indications of leakage at that fitting in the last 35k miles. I probably should replace it but not sure where or what to call it. Anyone know this info?
Thanks,

Marty
http://www.irv2.com/attachments/phot...6/IMG_0721.jpg

[DriVer]

"The fuel feed and return pipes and hoses extend from
the fuel sender to the fuel manager/filter. They are
secured with clamps and are routed along the frame
side member.

Some fuel feed pipes have threaded connections that
are sealed with replaceable O-rings seals. These
O-ring seals are made of special material, and should

only be serviced with the correct service part."

The clue to your situation would appear to be "replaceable O-ring seals" Note plural seals (more than 1)

I have found that you can get any size or type of O ring from a NAPA distributor. They have an O-Ring kit with many different size rings. Bring the one you have to NAPA and have them match it up. Buy 2 and place an O-ring on the land on the rear of the fuel feed tube and restore the one on the front.

Unless I pull my filter and check for O-rings I don't have a complete parts call out for the fuel feed lines. The service manual just states to R&R the fuel filter and it suggests: Tighten the fuel line to fuel filter nuts to

25 N-m (18 lb ft).

I don't expect this would be the source of your pressure leak on the rail. When I had 0 pressure, the problem was the pump the resolution was pump replacement. All is well at the moment with our fuel system.

[M&EM]

Quote:

Originally Posted by DriVer ---- Some fuel feed pipes have threaded connections that are sealed with replaceable O-rings seals. These O-ring seals are made of special material, and should only be serviced with the correct service part." The clue to your situation would appear to be "replaceable O-ring seals" Note plural seals (more than 1) I have found that you can get any size or type of O ring from a NAPA distributor. They have an O-Ring kit with many different size rings. Bring the one you have to NAPA and have them match it up. Buy 2 and place an O-ring on the land on the rear of the fuel feed tube and restore the one on the front. Unless I pull my filter and check for O-rings I don't have a complete parts call out for the fuel feed lines. The service manual just states to R&R the fuel filter and it suggests: Tighten the fuel line to fuel filter nuts to 25 N-m (18 lb ft). I don't expect this would be the source of your pressure leak on the rail. When I had 0 pressure, the problem was the pump the resolution was pump replacement. All is well at the moment with our fuel system.

Thanks Mike,
I believe I have found the correct O rings in a cabinet in my shop. They are VITON, brown colored, and 3/8" outside diameter with 062" dia. cross section. Although the filter connections have not leaked now or before, I will pull the filter tomorrow and replace/add the O rings.

Wasn't suspecting filter connection as a cause of key off pressure drop off. Just removed filter to further evaluate pressure bleed down loss to engine end or tank end of fuel delivery system.

Marty

[oemtech]

It's a #12 VITON O ring. You can get them lots of places.

[DriVer]

Quote:

Originally Posted by oemtech It's a #12 VITON O ring. You can get them lots of places.

√ You bet!

[wa7hra]

Quote:

Originally Posted by M&EM Replaced fuel filter(3rd time) 65k miles. This time I noticed an O ring was present on the outlet side fuel line but not on the inlet side. Apparently this O ring has been lost or was never there. Seems that the compression flange seals well without it. I have not had any indications of leakage at that fitting in the last 35k miles. I probably should replace it but not sure where or what to call it. Anyone know this info? Thanks, Marty http://www.irv2.com/attachments/phot...6/IMG_0721.jpg

Marty, I just looked at my new, still in the box, G3727 Fram fuel filter. I looked under the protective covers on each end and did not see any O rings. Are we both looking at the same thing???

Bob, wa7hra

[DriVer]

Quote:

Originally Posted by wa7hra Marty, I just looked at my new, still in the box, G3727 Fram fuel filter. I looked under the protective covers on each end and did not see any O rings. Are we both looking at the same thing???

Bob, wa7hra, The O-Rings are actually fitted on the fuel pipe and not in the fuel filter.

[M&EM]

Quote:

Originally Posted by wa7hra Marty, I just looked at my new, still in the box, G3727 Fram fuel filter. I looked under the protective covers on each end and did not see any O rings. Are we both looking at the same thing??? Bob, wa7hra

Bob check these photos of the O ring.
http://www.irv2.com/attachments/phot...6/IMG_0721.jpg

Marty

[wa7hra]

Quote:

Originally Posted by DriVer Bob, wa7hra, The O-Rings are actually fitted on the fuel pipe and not in the fuel filter.

OK, since I don't have a leak, I will not worry about it until I change the filter. If there are O rings I will considrer replacing them which is something I have never done in the past. If there are not, ho hum.

Bob, wa7hra

[codgerbill]

I dont have a manual so I do not know when it is time to replace the fuel filter. I will be taking the coach in for its spring checkup (Engine, generator, & chassis service). I was going to have them do a flush on the tranny fluid and also put some pure synthetic oil in the engine. Do I just have them change the fuel filter on general principals or is there something that will indicate the filter needs changing. I am the second owner (took possession in December and coach has 54,000 miles on it) and I dont know if the fuel filter was ever changed.

[DriVer]

Quote:

Originally Posted by codgerbill I don't have a manual so I do not know when it is time to replace the fuel filter.

I have taken the liberty to attach a Maintenance Schedule at the bottom of this post. To that please add, flush brake fluid every 2 years or 24,000 miles whichever comes first.

·

[max49]

If you're taking it in for Engine, generator, & chassis service, absolutely have the fuel filter changed. Alot of gas flows through that little thing.

[codgerbill]

Thanks Driver & Max.

I will be sure to include the filter replacement in the spring maintenance.

[oemtech]

If your missing the O ring be sure to replace it as it is what REALLY provides the seal. The taper in the filter matches the taper on the fuel nut but the real seal is done by O ring. Also be aware that the taper is NOT the standard taper used on brass fittings.