Changing Fuel Filters "gotcha moment"

[jelag]

I'm getting ready for the move out of our winter quarters to our next volunteer/host sight and was doing some catch up on the truck... .



My truck has 2 filters that I added to the fuel system when the truck was new... one is 10 micron and the other one is a 2 micron... . I was under the truck changing those... . its time... maybe 50K miles and the last time was back in 2010... their dated when I changed them last... .



So both are Fleetguard... and are from one of the class 8 applications where each is maybe 5" diameter and 10-12" high... . lots of capacity... . so I drained the water trap... can't remember when I last did that... I put maybe 4-6 oz of fuel in a jar... and the water was less than a 1/2 thimble full... . so I guess that I'm doing OK where I buy my fuel... actually as we travel, that's any truck stop... and I fill both tanks at once... .



So the primary filter actually both have a rubber washer, quad o-ring on the threads and I don't remember ever changing that quad ring... . but I screw on both filters and the truck leaks like a sieve as after I cycle the switch and than tighten the filters... I pull them both off and look at the quad ring... the quad ring on the filter housing is at least a 1/16" taller than the new quad ring in the box... I put both filters next to each other... . remember they both are from the same brand and carry the same part number the threaded portion of the filter is lower on the old filter than the new filter... I can lay a flat edge across the sealing gasket and see with my eyes that one threaded boss is lower than the other..... so I grab the new quad ring and set it next to the old one, still on the housing and can feel the difference in the two quad rings.....



Now I look at the quad rings on both new filters and they are the same with the same height from the boss to the outer gasket... . but both the old filters have the old style quad ring... .



Of course I'd pulled my drain bucket out from under the truck when I thought I had them tight... so now I've got a pint of fuel to clean up... at least its not that darn black oil from an oil change... . so in my notes that I keep for when and where I service my stuff..... trucks, cars, motorcycles, airless sprayer, part numbers, where I bought it, when it was done... . etc etc... ... . actually a great piece of software... . CARCare Desktop Edition...



Ah the fun of working on your own stuff and retirement...

 

[rbattelle]

Jim, I'm having trouble following you on this. Are you saying the ring on the new filter doesn't work with your filter head?

-Ryan

 

[jelag]

I'm sorry... the thickness on the seal over the threaded shaft is a different thickness... . thus the outer gasket won't seal when the filter is tightened on the old seal (quad ring)... . The old quad ring on the threaded shaft is at least a 1/16" thicker and the new filters would not tighten down until I changed the quad ring to the new ones... and the boss, (threaded portion of the filters) is different from the old one to the new one... . same brand and same part number. . Hope this helps. .

 

[Shadrach]

Call 1-800- 22 FILTER and talk to Fleetguard and see if they can help. Shad

 

[MLee]

So from now on your going to change all the gaskets!!!! thats in the kit, RIGHT??? Sounds like a design change on the filter housing.

 

[HHhuntitall]

So from now on your going to change all the gaskets!!!! thats in the kit, RIGHT??? Sounds like a design change on the filter housing.

BINGO! Fleetguard is making a lot of changes, pretty much cleaning up. Just like discontinuing the LF3349, which came on the 12v engines. They suggest upgrading to the LF3972, which is spec'd for the 24v... ... . Some of the changes include the use of different gaskets, of different thicknesses, which mount on the same filter heads, but perhaps in a different clearance..... somehow, it seems they are saving money doing this... . Perhaps this way they can only make a few gaskets across the board instead of many..... Not sure, but it's a pain sometimes, especially if you have older trucks and tractors.....