Replacing The Fuel Pump In A 2004 Discovery: Step-By-Step Guide

Changing the fuel pump on a 2004 Land Rover Discovery is a complex process that requires careful attention to detail. The fuel pump is located in the top of the tank, and while it is not necessary to drop the tank, removing the rear seats or side bins and pulling up the carpet is essential for accessing the fuel pump cover plate. This process may vary depending on the specific model and configuration of your Discovery. It is crucial to ensure that the fuel tank is less than 3/4 full before beginning any work. Once access is gained, the fuel pump cover plate must be carefully removed, taking special care with the screw heads to avoid damage. With the cover plate removed, the retaining ring that holds the fuel pump in place can be released using a hammer and screwdriver technique, being mindful that the fuel pump is spring-loaded. The electrical connector for the pump is delicate and should be handled with caution. The fuel lines are colour-coded, making it easy to identify the correct connections. It is important to clean the mating surfaces and reinstall the components in the reverse order of removal, ensuring a proper seal and no leaks.

Removing rear carpet and insulation pad

To remove the rear carpet and insulation pad of a 2004 Land Rover Discovery, follow these steps:

First, lift the rear carpet to access the fuel pump cover plate. If you have storage boxes, you may need to remove them to lift the carpet. You can also cut a circle in the carpet over the access panel to make it easier. Alternatively, make a few cuts in the carpet between the plastic trim pieces where the third-row seat clips into the floor.

Next, remove the rear insulation pad. This will expose the fuel pump cover plate, which you will need to remove. If the screw heads are rusted or stripped, use an 11/64mm/4.4mm titanium nitride-coated, split-point, high-speed steel bit to drill the heads off. Make sure to oil the bit and go slowly to avoid damaging the surrounding area.

Once the cover plate is removed, use a flat-head screwdriver to pry it off completely. Be careful not to damage the surrounding area. With the cover plate removed, you can now access the fuel pump assembly and proceed with the fuel pump replacement or repair.

Locating the fuel pump cover plate

To locate the fuel pump cover plate of a 2004 Land Rover Discovery, follow these steps:

• Remove the rear carpet and insulation pad.
• Locate the fuel pump cover plate. It should be accessible after removing the rear carpet. If you have third-row seats, you may need to remove the right third-row seat or cut a hole in the carpet to reach the access panel.

If the screw heads on the cover plate are rusted or stripped beyond repair, you will need to drill them out. Here are the steps to do that:

• Use an 11/64mm / 4.4mm titanium nitride-coated, split point, high-speed steel bit to drill the screw heads until they break off. Make sure to oil the bit and drill slowly to avoid breaking it.
• Once the screw heads are removed, use a flat-head screwdriver to pry off the cover plate.
• Use pliers to remove the rest of the screws by turning them counter-clockwise.

Removing the cover plate

To remove the cover plate of your 2004 Land Rover Discovery, you will first need to remove the rear carpet and insulation pad. Once you have located the fuel pump cover plate, check the condition of the screw heads. If they are rusted or stripped beyond repair, use an 11/64mm / 4.4mm titanium nitride-coated, split-point, high-speed steel bit to drill the heads until they break off. Be sure to use oil to keep the bit lubricated and go slowly.

Next, use a flat-head screwdriver to pry off the cover plate. Then, use pliers to remove the rest of the screws by turning them counter-clockwise. Vacuum the area to prevent debris from entering the fuel system. Spray liquid wrench onto the notches on the retaining ring to lubricate it.

Now, you can remove the wire harnesses and the fuel lines. To remove the "fuel out" line, push on the white plastic tab towards the line and then pull the line away. Remove the fuel return line in the same way. Position a flat-head screwdriver against a notch and lightly hammer it until the retaining ring starts to turn. Repeat this process for each notch until you can remove the ring by hand.

Finally, carefully remove the fuel pump assembly by pulling straight up. You will need to turn it to the right to remove it completely, and some fuel will spill, so be prepared to catch it in a suitable container.

Removing the wire harnesses

To remove the wire harnesses from a 2004 Land Rover Discovery, you must first disconnect the negative battery terminal. Then, disconnect the fuel pump harness from the tank. Remove about a foot of the tape and black plastic conduit from the harness.

Make sure you are not dealing with the fuel pressure sensor connector. If the old wiring does not match the new wiring, refer to the diagram that comes with the new wiring. Cut the first pair of wires about two inches away from the electrical connectors. Then, stagger the rest of the cuts by about an inch and a half and strip the wires.

Crimp the vehicle wiring to the new wiring harness with the supplied connectors on all wires. Ensure that no insulation is trapped between the electrical connector crimp. Shrink the insulation with a heat gun to secure the connections, keeping this process away from any fuel. When the glue begins to come out of the connector, the seals are weather-tight.

Finally, install the black plastic conduit and re-tape the wires.

Removing the fuel lines

To remove the fuel lines from your 2004 Land Rover Discovery, you'll need to gather a few tools, including screwdrivers (both Phillips and flat-head), a hammer, and needle-nose pliers. Here's a step-by-step guide:

• Accessing the Fuel Pump Assembly: Start by removing the rear carpet and insulation pad. Locate the fuel pump cover plate and remove any screws or bolts holding it in place. Be careful not to strip the screw heads; if they are rusted or stripped, use a suitable drill bit to drill the heads until they break off.
• Removing the Fuel Pump Assembly: Use a flat-head screwdriver to pry off the cover plate. With the cover plate removed, you'll have access to the fuel pump assembly.
• Detaching the Wire Harnesses: Disconnect the wire harnesses connected to the fuel pump.
• Removing the "Fuel Out" and Return Lines: To remove the "fuel out" line, locate the white plastic tab near the line and push it towards the line. Then, gently pull the line away from the tube. Repeat this process for the fuel return line.
• Releasing the Retaining Ring: Place a flat-head screwdriver against one of the notches on the retaining ring. Lightly tap the screwdriver with a hammer until the retaining ring starts to turn. Repeat this process for the next notch, if necessary, until you can loosen and remove the ring by hand. Be sure to spray a liquid wrench onto the notches to lubricate them before attempting to turn the ring.
• Handling Fuel Spillage: Keep in mind that when you remove the fuel pump assembly, some fuel may spill, so have a suitable container or absorbent material ready to catch any spilled fuel.
• Removing the Fuel Pump: With the retaining ring removed, carefully lift the fuel pump assembly straight up. You may need to turn it slightly to the right to clear the leveling arm without bending or breaking it.

Remember to clean all mating surfaces and reinstall the components in the reverse order of removal. Ensure you have a new rubber gasket for the top of the tank lip before installing the new fuel pump.

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