Fuel Filter Autopsy
 

This vehicle had 33,000 miles on it. Previous owner lived in a farm house, but on a paved road, so the vehicle was operated in a pretty typical environment.

I hacksawed the case open and removed the filter element. Fuel flows from outside to inside, so the outer space is the dirty side of the filter.

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Outside

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Filter material pulled out. Note that at the seams it's much lighter than elsewhere.

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View of the back side of the filter material. Much lighter on the other side.

I'm going to guess that the initial color was light brown.

The recommended change interval is 30,000 miles. Given how dirty this one is, in my estimation that's a pretty good recommendation.

I wonder how your fuel pump sock looks.