TC-35D fuel filter gasket "O" ring

[farmacist]

I just changed my fuel filter for the (aprox 10th time) yesterday and decided to lay on my back and look to see the condition of the "O" ring that the manual says seals the top of the filter to the top of the filter assembly. There was no "O" ring there, maybe it stuck to a filter in the past and got thrown out, and it was not on the one I just took out so it ran for at least the last 150 hrs without that "O" ring. I suggest that you all check yours next time to be sure it is there. Have a good day, Frank

 

[jedjoe]

Thanks, Frank.

That "O" ring, if memory serves, doesn't actually attach to the filter itself. I believe it seals the joint between the upper metal portion of the assembly and the plastic bowl. If I'm right about that, I think the only problem that would create for you is that diesel may weep out of the assembly at that joint. Does it?

 

[farmacist]

Finally I have finished my investigation. My "o" ring had fallen out and I had been replacing my fuel filter each time without the top small "O" ring in place to keep crud out of my injector system. With the loader on you have to really squat down, lay on your back, or use a mirror to confirm that the "O" ring is still in place. It does not look like it should ever fall out but mine did. The "O" ring fits on a short 1/2" pipe that fits down inside the top of the fuel filter cartridge. You can see it clearly if it is still there. The part # is SBA052100160 . I suggest that you all check next time you change your fuel filter to confirm that your "O" ring is still in place. I did not cause a problem that I know of but the crud could still be in a line waiting for an un-opportune time. Good luck , Frank
Note I am NOT talking about the 3inch "O" ring that seals the plastic bowl to the assembly.

 

[jinman]

Illustration attached. I think item 21 is the subject of Frank's post.

 

[farmacist]

My thanks to Jim. Right on, as illustrated in the above diagram, "O" ring #21 fits down INSIDE of #25 (the fuel filter). Our fuel filters do NOT have a neck like is pictured in the diagram, what is shown as a neck on the filter is actually attached to the base of the fuel filter unit (which does not seem to have a number in Jim's diagram) and then the "O" ring slips over that tube and is then inserted into the top of our filters. Thanxs Jim, Frank

 

[jedjoe]

Always learning something new on this site. Thanks for clarifying. The next time I change my fuel filter, I'll check that other "O" ring.