Replacing Fuel Filter

January 20, 2003

Note: This procedure is for 1998 Ford F-150 4x4 with 4.6L V-8, 4R70W automatic tranny. 1997-2003 models may be similar. Fuel is dangerous - avoid open flame or sparks, wear safety glasses while under the vehicle.

Tools Required

safety glasses
long, large slot screwdriver
OTC #7361 fuel line disconnect tool set $15.26cdn + tax
large bin or catch tray (for fuel spillage)

Parts Required

fuel filter (Motorcraft FG-872) $20.24cdn + tax

Total Cost:

$40.65cdn with taxes, local Ford dealer for both items.

Procedure

remove the plastic trim on the passenger side door sill.
remove the plastic trim covering the passenger side kick panel.
locate the inertia-sensitive fuel cut-off switch in the middle of the panel. It has a round top where you can insert a small finger to hit a "reset" button, and it has a wire connector off the bottom.
disconnect the wire from the inertia switch (this cuts power to the fuel pump).
insert the key into the ignition and start up the vehicle (if it runs it will only run for a second or two - usually it won't even start). This relieves the fuel pressure in the fuel lines by the filter.
locate the fuel filter on the vehicle, underneath, inside the frame rail approximately under the driver's seat.
use compressed air or a rag to make sure the fittings that fit on the filter are clean. Sometimes dirt on the fittings can make them hard to remove.
with your fingers or a screwdriver unfasten the metal safety clips on either fuel fitting and move them aside (they can't be removed from the fuel line).
place a pan or drain container under the vehicle to catch excess fuel that drips from the fuel lines or filter.
use the grey colour fuel line tool and snap it onto the filter with the wide diameter end closer to the filter. The narrow end fits into the fuel fitting. Push it into the fuel fitting away from the filter. It helps to push the fuel line all the way onto the filter, then push the plastic tool into it. While the plastic tool is inserted, pull the fuel line away from the filter. It should pop off without too much effort. I had a problem getting the output side line off the old filter, the trick was to push the fitting onto the filter as far as possible.
Once both fuel lines are out of the way (you may have to string them up a bit or at least the fuel tank line to slow the dripping of gasoline.
With the large screwdriver pry up the metal bracket that holds the filter and as you're prying it open slide the old fuel filter to the rear of the vehicle until it's out of the bracket, then just remove it. It takes quite a bit of force to hold the bracket open for this. Remember, NO SPARKS or open flame while you're doing this. Keep the filter horizontal to avoid spilling excess fuel out of it. I poured the extra fuel in the filter back into my tank.
Put the new filter into the bracket, holding the bracket open with the screwdriver.
Push on the fuel lines on either side.
Push on the safety retainers and make sure they are on 100%.
Check the connections, make sure they don't pull off.
Replace the inertia switch connector.
Start the vehicle, check for leaks.

Haynes manual indicates this should be a yearly procedure. I still had the original filter on it which has done 108972kms. I should of changed it a lot earlier. Personally I wouldn't change it so often, perhaps every 2 years.

The Lightning owners have had problems with their filters clogging and starving for fuel leading to engine damage so if you have a Lightning consider changing it at the latest every 12 months. If you run lean under high supercharger boost your motor may go "bang".

Fuel vapours can make you whoozy so don't do this in an enclosed garage, your brain will thank you for it.

It may be an idea to keep a fire extinguisher handy just in case something horrible happens. If you detect a fuel leak shut off the motor right away and correct the situation. Fuel is dangerous.