Black fuel filter?

[FParisi]

Just did my 1st fuel filter change at 15,400mi. It IS a bit of a PIA but should be easier next time.

My question is - the old filter element came out + is a dark gray/black - is that normal at filter change?

Or should I change more often? I've thought of doing more + better filtration.

Thanks

Frank

 

[AABEN]

This is what your filter should do. My filter looks like a big chunk of coal. It could be some algae in your fuel tank. I have a 100Gal fuel tank in the back of the truck in the hot sun it will start to grow algae this is black when you change the fuel filter. This is very easy to happen if you have a above ground fuel tank are buying from above ground tank this heat this year has been good for this to happen.

 

[jelag]

When I had Fords, they would have a problem where engine oil could pass into the fuel system and the fuel filter would trap the oil... and turn it black... .

One of my trucks (dodge's) is now doing this and I've tracked the problem to the injection pump... or as least so I've been told by a Cummins tech... . he tells me that there is a problem and the oil is going into the injection pump, part of it is returning to the tank and than back to the filter... . my other trucks seem to have normal fuel filter changes and their not a problem...

He also said to watch the oil level which I am... and its going down between routine service by 2 qts or so. . as soon as I confirm his diagnosis I'm going to change the pump... .

Can anyone here confirm this...

 

[GaryOwen]

You normally have asphaltenes in the fuel which will turn your fuel filter black. The following is an explanation from the Filter Manufacturers Council concerning asphaltenes.



All diesel fuels to a degree contain a substance known as asphaltene. Asphaltene is a by-product of fuel as it oxidizes. Asphaltene particles are generally thought to be in the half micron - 2-micron range and are harmless to the injection system, as they are soft and deformable. As these tiny particles pass through the filter media they tend to stick to the individual fibers. If you were to cut open a filter that had choked after a normal service interval you would see a black, tarry substance on the dirty side of the element; this is asphaltene (oxidized fuel).

 

[jelag]

Geez, thanks Gary but we just changed our filters on a CAT engine we have... . 10 micron primary and 2 micron secondary like we have on our Dodges... . and neither of those filters were black from 50K miles..... based on just looking down inside with a flashlight... . but I do have a 10 micron we just changed off our 08 5500... . its still sitting in the drain bucket we use... I'll cut it apart this week and see what it looks like..... I'm now confused... .

 

[FParisi]

Thanks Gary

Until we got the filter in a canister I never saw the actual filter material. I never cut an old spin on filter open.

Jelag - let us know what you find. I don't know if looking into a filter is looking at the intake or outlet side.

Frank

 

[gsbrockman]

Picture of mine.............

I've been sticking with about an 8,000 to 9,000 mile service interval on oil (5W40 Rotella-T Synthetic), oil filter, and fuel filter, along with a tire rotation. This was the first replacement fuel filter for the fuel filter/shell combo I installed around January of this year. About 3,900 miles of it was towing (avg mpg towing of 13. 4 +/-) and the rest was non-towing (16. 8 mpg +).



Greg



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[FParisi]

Thanks Greg

That is exactly what mine looked like. Greg's reply about the asphaltene particles is the answer. Thanks for the reassurance!

Frank

 

[gsbrockman]

Thanks Greg

That is exactly what mine looked like. Greg's reply about the asphaltene particles is the answer. Thanks for the reassurance!

Frank

Gary's explanation makes me wanna go saw my filter into halves!!!!!!! :-laf

 

[FParisi]

Oops. That was Gary with the info re: asphaltenes. Gotta give credit!

Frank