Cleaning Fuel Filter

The fuel filter catches particulates before they reach the injectors. A clogged filter will cause low fuel pressure and can cause lean running or injector damage.

If a fuel pressure check shows low pressure (below 45 PSI at idle), inspect the fuel filter before assuming a failing pump. See Checking Fuel Pressure.

Location

Cockpit tank cars (6-gallon behind-the-seat system): The fuel filter is located inside the tank enclosure. Access it by opening or removing the tank enclosure cover.

Older 5-gallon tank cars: The filter is an inline unit in the fuel feed line between the tank and the fuel rail.

Procedure

1. Relieve fuel system pressure: remove the fuel pump fuse or use the dash fuel pump switch to shut off the pump, then crank the engine briefly until it stalls or cycle the key without starting to allow pressure to drop.

2. Place rags under the filter connections to catch residual fuel.

3. Disconnect the filter from its fittings. Note the flow direction arrow on the filter body before removal.

4. If the filter uses a cleanable mesh element: flush backward with compressed air or clean fuel to dislodge debris.

5. If the filter uses a paper element: replace it — paper filters cannot be cleaned.

6. Reinstall with the flow arrow pointing toward the engine. Verify all connections are secure.

7. Restore power to the fuel pump, cycle the key several times to prime the system, and inspect for leaks before starting the engine.

Work away from ignition sources and have a fire extinguisher within reach when working on the fuel system.