Ford 7.3L Powerstroke Fuel Filter Plugged With Black Residue


Problem: Fuel filter plugged with black, scummy residue

Causes: Bacteria in tank

Solution: Treat with biocide to kill the bacteria. Then, clean out the system with back-to-back treatments of Diesel Extreme. Replace fuel filter.


Believe it or not, micro-organisms can thrive in a diesel tank with a little bit of moisture in it. If the fuel filter is plugged with a black scummy substance, or if there is a dark scummy substance or “carpet look” in the tank, you likely have a bacteria problem. Other symptoms may include dark or hazy fuel, sludge build-up in tanks, loss of power or excessive smoke.
To combat this, use the MP8 Biocide available from Lubrication Specialties by calling 1-800-341-6516. After you treat with the biocide to kill the bacteria, follow up with back-to-back treatments of Diesel Extreme to clean out the system and replace the fuel filter.

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