Replacing The Fuel Pump In A Jeep Yj: Step-By-Step Guide

Replacing the fuel pump on a Jeep YJ is a complex task that requires careful attention to safety and a range of tools and parts. The process involves disconnecting the battery, removing the fuel tank, and working with various components and connections within the tank. While it is possible to replace just the fuel pump, some people opt to replace the entire assembly, which can cost around $200. Before starting the replacement process, it is important to ensure the fuel tank is nearly empty to avoid spills and manage the weight of the tank during removal.

Disconnect the battery, remove the license plate bracket, gas cap, filler neck shroud, and rear driver tire

Disconnecting the battery is an important first step when replacing the fuel pump on your Jeep YJ. This is a safety precaution to avoid any unwanted sparks while you work.

Next, you'll need to remove the license plate bracket and the gas cap. This will give you better access to the filler neck shroud, which you should also remove so that the filler hose can move around more freely.

Now, you'll need to support the axle and remove the rear driver-side tire. This will give you the space and access you need to start working on the fuel tank. It's a good idea to support the fuel tank with jack stands or something similar at this point.

There are seven 1/2" bolts holding the gas tank in place. You can use air tools or a crescent wrench to remove them. The four rearmost bolts should come off without too much trouble, but the three front bolts may be more challenging. You may need to use a combination of tools to access them effectively.

Once the bolts are removed, you can start to lower the fuel tank. Be prepared for it to get hung up on other components, such as the exhaust pipe hanger on the passenger side. You may need to use a pry bar to gently wedge it free. As you lower the tank, be mindful of the vent lines and filler hose, which will also need to be disconnected.

Support the fuel tank with jack stands and remove the bolts holding the gas tank

To replace the fuel pump in a Jeep YJ, you'll need to access the fuel tank by lowering it from the vehicle. This can be done by using a jack to support the tank while you remove the bolts holding it in place. Here's a step-by-step guide to help you through the process:

Step 1: Prepare the Vehicle

• Disconnect the battery to avoid any unwanted sparks.
• Remove the license plate bracket and the gas cap.
• Take off the filler neck shroud so that the filler hose can move freely.
• Support the axle and remove the rear driver-side tire for better access.

Step 2: Jack Up the Fuel Tank

• Place a jack under the fuel tank and adjust it to a height that allows you to comfortably work on removing the bolts. You can use a hydraulic floor jack, an ATV jack, or a transmission jack for this purpose.
• If using a jack with a narrow saddle, place a piece of wood between the jack and the fuel tank to distribute the load and prevent damage to the tank.

Step 3: Secure the Fuel Tank with Jack Stands

Once the fuel tank is supported by the jack, place jack stands on each side of the tank to keep it securely in place. Ensure that the jack stands are positioned on stable ground and are capable of bearing the weight of the tank.

Step 4: Remove the Bolts Holding the Gas Tank

• There are typically seven 1/2" bolts holding the gas tank in place. Use the appropriate tool, such as an air ratchet or a crescent wrench, to remove these bolts.
• The bolts may vary in accessibility, with some being more difficult to reach than others. Take your time and work carefully to avoid damaging the surrounding components.
• As you remove the bolts, gradually lower the fuel tank by adjusting the jack. The tank may get hung up on certain components, such as the exhaust pipe hanger. Use a pry bar or similar tool to gently free the tank from any obstructions.

Step 5: Lower and Remove the Fuel Tank

• Continue to lower the fuel tank by adjusting the jack, being cautious as the tank is heavy, especially if it still contains fuel.
• Disconnect the smaller vent lines and the filler hose. You may need to loosen hose clamps that are difficult to access.
• Once all connections are released, carefully lower the fuel tank to the ground.

By following these steps, you will have successfully supported the fuel tank with jack stands and removed the bolts holding the gas tank, allowing you to access and replace the fuel pump in your Jeep YJ.

Loosen the retaining ring holding the pump in the tank with a hammer and a block of wood

To loosen the retaining ring holding the pump in the tank, you will need a hammer and a block of wood. The block of wood should be placed on a tab on the ring, and then gently tapped with the hammer in a counter-clockwise direction to loosen it. It is important to be gentle and not use something with a sharp metal edge, as this could damage the ring. This step may take some time and effort, as the ring is usually tight. Once the retaining ring is loosened, you can proceed to the next steps of removing the fuel pump assembly.

The fuel pump assembly will contain gasoline, so it is important to be cautious and pour it back into the tank to drain it. Be careful not to break the sending unit float during this process. The next step is to remove the bottom filter, which can be pulled off. Then, you can disconnect the sending unit by carefully releasing the small tab holding the connector.

The top plastic portion of the assembly is spring-loaded onto the aluminum housing. To release it, carefully push in three tabs (circled in green) past the retaining indents in the aluminum canister. You will need to use a flathead screwdriver to carefully pry the tab for the fuel pump connector and gently pull it out. This step requires caution, as the wires for the fuel pump may be rigid from being soaked in gasoline. If these wires break, you will need to purchase a new assembly.

Now, you can set the plastic top aside and remove the spring between the fuel pump feed tube and the plastic top. Try to pull out the tube as well, noting its orientation.

At this point, you should be able to see the fuel pump clearly. If you reach inside the housing and grab the pump, it might not come loose right away. This is because the fuel pump is secured to a secondary filter at the bottom of the housing. To release it, try flipping the housing upside down so that the fuel pump is hanging, and then gently tap it on a block of wood. Think of this step like trying to get the last bit of ketchup out of a bottle by tapping it gently on the counter.

By following these steps, you can successfully loosen the retaining ring and remove the fuel pump assembly for replacement.

Remove the assembly from the tank and disconnect the sending unit

To remove the assembly from the tank, you will need to have a hammer, a block of wood, and some flathead screwdrivers. The assembly will contain gasoline, so be sure to drain it into the tank. Be careful not to break the sending unit float.

To disconnect the sending unit, you will need to locate the small tab holding the connector in place. Be careful not to bend it too much as it is delicate. Once the sending unit is disconnected, you can move on to removing the top plastic portion of the assembly. This is held in place by three tabs that need to be carefully pushed past the retaining indents in the aluminium canister.

After the tabs are released, the plastic top piece will still not be completely free. You will need to use a screwdriver to carefully pry the tab for the fuel pump connector and gently pull it out. Again, be cautious as the wires for the fuel pump may be rigid from years of being soaked in gas, and if you pull too forcefully, you could break the wires.

Now that the sending unit and the top plastic portion have been disconnected, you can proceed with the rest of the fuel pump replacement process.

Reinstall the new fuel pump, making sure the washers are in place

Now, it's time to install your new fuel pump. First, make sure the two washers are in place – the rubber one followed by the metal one. If you're having trouble, grab a long, thin piece of wire or a straw, put the washers on, and slide them down into the little area at the bottom where they sit. Next, carefully set the fuel pump assembly in place, using your fingers or a long, blunt-edged tool to press it in. You'll know it's in place when you can hold the whole assembly upside down without the pump falling out.

If you're struggling to get the washers in place, there are a few tricks you can try. Try using a piece of wire or a straw—something skinny and long. Put the washers on, and then slide them down into the bottom where they belong. Alternatively, you can try gently tapping the washers into place with a hammer and a block of wood. Just be careful not to use too much force, as you don't want to damage the washers or the surrounding components.

Once the washers are in place, carefully set the fuel pump assembly into position. Use your fingers or a long, blunt-edged tool to gently press it into place. You'll know you've successfully installed the new fuel pump when you can hold the entire assembly upside down without the pump falling out. It should be nice and secure.

Now that the new fuel pump is installed, you can move on to reinstalling the plastic top. Use one or both of your flathead screwdrivers to pry back the tabs on the housing, releasing the retaining clip for the fuel pressure regulator. Be careful not to apply too much force, as these components can be delicate. Gently remove the old regulator and put the new one in its place. Remember to reinstall the retaining clip when you're done.

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