Replacing Fuel Pump In '98 F150: Step-By-Step Guide

Changing the fuel pump in a 1998 F150 is a complex process that requires a good level of mechanical ability. The fuel pump is accessed by removing the bed of the truck and lifting it with the help of two or more strong individuals or a machine. The fuel pump is then disconnected by removing the electrical connector and fuel lines, and unscrewing the bolts that secure it in place. A new pump can then be installed, and the old pump's gasket can be reused to create a seal.

Disconnecting the fuel tank

Step 1: Remove the Negative Battery Terminal

Use an 11mm wrench to disconnect the negative battery terminal. This is an important safety precaution to prevent any accidental electrical discharge while working on the fuel system.

Step 2: Loosen and Remove the Fuel Filler Neck and Vent Hose

Loosen the fuel filler neck bracket and vent hose bracket from the metal line using an 8mm socket and ratchet. You may need to use a metal pick to carefully separate the hoses from the metal tube. Remove the vent hose from the tank by loosening the hose clamp with an 8mm socket.

Step 3: Disconnect the Sensor and Fuel Pump Connector

Disconnect the sensor on the fuel tank. This sensor is typically attached to the body or frame of the vehicle. Use a flat-bladed screwdriver to release the tab and disconnect the connector from the fuel pump.

Step 4: Unlock and Disconnect the Fuel Lines

Use a long, flat-bladed screwdriver to unlock and pop off the locks on the fuel lines. Be careful not to damage the lines. You will need a fuel line disconnect tool to separate the pressure and return lines from the fuel tank.

Step 5: Remove the Vent Hose

The vent hose is connected to the fuel tank with a spring clamp. Use needle-nose pliers to squeeze and remove the spring clamp, then carefully lift the vent hose off the tank.

Step 6: Prepare for Fuel Tank Removal

At this point, you will need an assistant to help you with the fuel tank removal process. Ensure that you are working in a well-ventilated area and put on safety gear, including gloves and eye protection. It is important to note that the fuel tank should be almost empty to reduce the risk of spillage.

Step 7: Undo the Fuel Tank Straps

Undo the tank straps by loosening the bolts on each side of the tank. One strap may have a 13mm bolt, while the other may have a 17mm bolt. Let the straps hang down, and carefully lower the fuel tank with the help of your assistant.

By following these steps, you will have successfully disconnected the fuel tank in your 1998 F150, allowing you to access and replace the fuel pump. Remember to work carefully and seek assistance if needed to ensure a safe and effective repair process.

Removing the fuel tank

Before you begin, make sure you have the right tools for the job. You will need an 11mm wrench, an eight-millimetre socket and ratchet, a metal pick, a flat-bladed screwdriver, a disconnect tool, needle-nose pliers, a 10mm socket and ratchet extension, a 13mm bolt, a 17mm bolt, a rag, a brush, compressed air and a blow gun. It is also recommended to have an assistant to help you lift the gas tank.

First, remove the negative battery terminal using an 11mm wrench. Next, remove the fuel filler neck with an eight-millimetre socket and ratchet. Loosen the hose clamp of the vent hose and hold these off the middle lines. If necessary, use a metal pick to separate the hose from the metal tube. Move the filler neck hose and get the vent hose off. Remove the vent hose from the tank with an eight-millimetre socket and undo the hose clamp. Remove the hose.

Now, disconnect the fuel pump connector. Use a flat-bladed screwdriver to push the connector in and remove it from the fuel pump. To remove the locks from the fuel lines, use a long flat-bladed screwdriver to pop them off. Disconnect the pressure and return lines with a disconnect tool.

Finally, remove the vent hose from the fuel tank. Squeeze the spring clamp with some needle-nose pliers and remove it. With everything at the top of the tank disconnected, you can now undo the tank straps. Loosen the 13mm bolt from one side of the strap and let it hang down. Remove the 13mm bolt from the second strap.

At this point, you should have someone to help you. Even though the tank is pretty much empty, it is still recommended to have an assistant to hold one end while you hold the other end and lower the tank down.

Removing the fuel tank and sending unit

To remove the fuel tank and sending unit of a 1998 F150, you will need to first disconnect the fuel tank. Remove the negative battery terminal with an 11mm wrench. Loosen the fuel filler neck bracket and the vent hose bracket from the metal line. Remove the vent hose from the tank and disconnect the sensor and the fuel pump connector. Remove the locks from the fuel lines with a flat-bladed screwdriver and disconnect the pressure and return lines with a disconnect tool.

Now, you can remove the fuel tank. Have an assistant hold the gas tank while you loosen the bolts from the straps. Let the straps hang down and lower the fuel tank.

Work in a well-ventilated area and clean any dirt and debris from around the sending unit. Remove the bolts from the top of the sending unit and lift the unit up and out.

To install the new fuel tank and sending unit, lower the sending unit into the tank and tighten the bolts. Lift the gas tank into place and tighten the bolts to the fuel tank strap. Reinstall the filler neck hose and hose clamp to the metal line. Reinstall the vent hose and hose clamp to the metal line and reconnect the sensor on the fuel tank. Reinstall the vent hose on the fuel tank and reconnect the negative terminal. Cycle the key three times to prime the pump.

Installing the fuel tank and sending unit

To install the fuel tank and sending unit, you will need to follow these steps:

• Lower the sending unit into the tank.
• Tighten the 10mm bolts to the sending unit evenly.
• Lift the gas tank into place with the help of an assistant.
• Tighten the 10mm bolts to the fuel tank strap.
• Remove the caps from the pressure and return lines.
• Connect the return lines and clip the safety catch into place.
• Connect the vacuum hose and hose clamp to the fuel tank.
• Connect the electrical sensor.
• Reinstall the filler neck hose and hose clamp to the metal line.
• Reinstall the vent hose and hose clamp to the metal line.
• Reconnect the sensor on the fuel tank.
• Reinstall the vent hose on the fuel tank.
• Tighten down the tank straps.

Installing the fuel tank

To install the fuel tank, you'll need to first clean the dirt and debris from around the sending unit. Then, lower the sending unit into the tank and tighten the 10mm bolts to the sending unit evenly.

Next, lift the gas tank into place with the help of an assistant and tighten the 10mm bolts to the fuel tank strap.

Now, reconnect the fuel tank by removing the caps from the pressure and return lines, connecting the return lines, and clipping the safety catch into place. Then, connect the vacuum hose and hose clamp to the fuel tank, and connect the electrical sensor.

Reinstall the filler neck hose and hose clamp to the metal line, and reconnect the sensor on the fuel tank. Reinstall the vent hose on the fuel tank and tighten down the tank straps.

Finally, reconnect the negative terminal with an 11mm socket and ratchet, and cycle the key three times to prime the pump.

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