This fuel filter write-up is one more of my "Basic Maintenance" threads and pertains to '87-'95 2.5L and '91-'95 4.0L YJ models.
Today a fellow JF member WhatsWrong
came to my house so we could do some work on his '93 4.0L YJ that he needed to get done. One of those things was a fuel filter replacement on his nearly pristine Jeep. Even though his Jeep is in excellent condition, it might be possible that the previous owners may have never changed the fuel filter. Since he has recently acquired the Jeep, he has been working on getting all the little things sorted out. If your YJ is new to you, a fuel filter replacement is a cheap bit of insurance and can be accomplished in just a few minutes.
Start with the correct fuel filter in the brand of your choice. Note that it has been marked "IN" and "OUT" indicating the direction of fuel flow, "IN" meaning into the filter from the tank, and "OUT" meaning out of the filter to the engine.
Remove the gas cap to release pressure in the tank.
Locate the schrader valve on the fuel rail.
Remove the cap & place some old rags around the valve.
Depress the stem in the center of the valve to release pressure from the line. The rag is there to absorb the fuel.
CAUTION!!! The fuel in the rail is under extreme pressure, exercise caution when releasing pressure to avoid being sprayed by fuel! Safety glasses are advisable.
The fuel filter is located underneath the Jeep on the frame rail, just forward of the rear tire on the driver's side. It has a protective guard plate attached with 4 screws.
The are 2 screws on the underside of the frame rail.
The remaining 2 screws are on the side of the frame rail.
Loosen the clamps for the inlet & outlet closest to the filter body before removing the filter clamp bolt. This will hold the filter steady while loosening the clamps.
CAUTION!!! There will still be plenty of fuel in the lines & filter! Eye protection is a minimum requirement!
Here you can see the bolt that is on the clamp. Once you remove the bolt, the top portion of the clamp that is hinged to the lower portion behind the filter can be removed.
Now the filter can be removed.
CAUTION!!! A lot more fuel than you think will still be in the filter! BE CAREFUL!
Install the new filter, paying close attention to the direction of flow as indicated on the new filter. Tighten the hose clamps securely, reinstall the filter clamp & bolt, and finally the guard plate.
Reinstall the cap on the gas tank & on the schrader valve on the fuel rail. Get in the Jeep & turn the key to the "ON" position for at least 10 seconds and then off again. Repeat this cycle at least 7 or 8 times, this will help refill the lines & filter and also build some pressure in the system. Failure to do so will result in a much longer & harder initial start-up.
Lastly, there are some things to keep in mind:
1) Check for leaks as soon as you restart the engine. If there is a leak, the sooner you know about it, the better!
2) Check the hoses for signs of deterioration and replace them as needed. The 2 small hoses located at the filter are distinctly different sizes, and are a dealer item only, to the best of my knowledge.
This is an extremely easy project for even the most inexperienced novice. It's a good way to start learning about your Jeep, and building your mechanical skills slowly & confidently.
Thanks again to fellow JF member WhatsWrong
for allowing me to use his YJ in this write-up!