Fuel Filter Installation Instructions

This is the general instructions for replacing the filter assembly and filter elements for your fuel water separator:

  • Clean any debris or dirt away from the die-cast head and filter fitting joints prior to removal.
  • Place a suitable container below unit to collect fuel and other contaminants.
  • Close fuel valve at fuel tank or upstream of filter.
  • Open drain plug by rotating to the left and drain contents of filter bowl into catch container.
  • Spin element and bowl off together (use a strap wrench on element), then unscrew bowl from element.
  • Clean filter bowl, and bowl O-ring gland with dry cloth or paper towel.
  • Clean sealing surface of die-cast cap and remove dirt, debris, etc.
  • Apply a light layer of lube oil to new gasket seal and bowl O-ring, which are supplied with element.
  • Place gasket seal onto top of replacement element, make sure it is pressed into locking tabs to hold into place for assembly.
  • Place O-ring into drain bowl then reconnect bowl to filter element. Shake bowl gently as screwing onto element to ensure O-ring “seats” properly into bowl gland. A properly “seated” O-ring should not stick out the sides of the drain bowl. If O-ring does not seat properly unscrew drain bowl and repeat this step. NOTE: If this O-ring is not “seated” properly in the bowl gland, the system will leak and has high potential to cause a fire.
  • Tighten snugly by hand – do not use tools to tighten.
  • Prime fuel system if necessary per manufacturer’s procedure.
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When replacing your filter remember gasoline is a very highly flammable substance. Make sure the engine to your device is turned off, the engine and surrounding components are cool to the touch, and you have the necessary fire suppression equipment nearby in case there are any mishaps. Keep heat, sparks, and flame away from the filter and clean up any spills immediately.

CFS’s units are produced with a 10-micron filter and are not suitable for use as a suction side filter with electric fuel pumps and carbureted systems. This application requires an 80- to 100-micron screen. Use of a 10-micron filter causes cavitation in the pump, leading to premature failure of the pump. Also, filters are not designed to separate oil from gas in blended fuel mixtures. Do not use them in these applications.

In marine applications, CFS’s products are not to be used in the engine compartment. CFS’s products include a clear acrylic plastic bowl, and these materials are not certified for in-compartment applications. You should only use products with a metal drain bowl in these applications.

Element replacement should be after every 100 hours of use, or when there is a noticeable power loss, whichever comes first. Note, it is highly recommended to carry an extra replacement element in case the need to replace the filter arises unexpectedly.