Replacing Fuel Pump In Chevy Truck: Step-By-Step Guide

Replacing a fuel pump on a Chevy truck is a complex task that can be done at home to save money. It is recommended to schedule an appointment with a Chevy vehicle service centre to let an expert handle the job. However, with the right tools and safety precautions, it can be done at home in a few hours. The process involves relieving fuel line pressure, lifting the truck, removing the fuel filler neck, disconnecting fuel tank lines, power lines, and gas tank straps, removing and replacing the fuel pump, and reinstalling the gas tank. The fuel pump is located inside the fuel tank, so the tank must be removed to access it. This is a significant undertaking but can be made easier by following step-by-step guides and videos available online.

Relieve fuel pressure

To relieve fuel pressure in a Chevy truck, you can try the following methods:

• Remove the fuel pump relay from the fuse box and attempt to start the vehicle. The vehicle will stall, but this relieves the fuel pressure.
• Start the engine and let it run until it stalls. This will relieve the pressure in the system.
• Push the Schrader valve on the fuel rail, which will relieve the pressure, but fuel will go everywhere.
• Start the truck and pull the fuel pump fuse.
• Remove the gas cap.
• Use a fuel pressure gauge to relieve the pressure.
• Disconnect the negative battery cable.

Disconnect the battery

Disconnecting the battery is one of the first steps to take when replacing a fuel pump on a Chevy truck. This is an important safety precaution to prevent any sparks while you work around the fuel tank.

To disconnect the battery, first, locate the battery under the hood of the truck. You will need to disconnect the ground cable from the battery. This is usually held in place with a clamp or bolt. Loosen the clamp or remove the bolt with the appropriate tool and carefully lift the cable away from the battery terminal.

It is recommended to use safety goggles and gloves when handling the battery, as there may be a small amount of acid present. Be sure to also refer to your Chevy truck manual for any model-specific instructions or differences.

Once the battery is disconnected, you can proceed to the next steps of replacing the fuel pump, such as relieving the fuel pressure and removing the fuel filler neck from the tank.

Raise the vehicle

To replace the fuel pump on a Chevy truck, you will need to raise the vehicle to gain access to the fuel tank. This can be done by using jack stands or drive-on ramps to safely lift the truck. If you don't have access to a lift, it is recommended to use four jack stands and lift the entire truck, rather than just the rear end. Place the jack stands in the manufacturer's recommended locations on level ground.

Once the vehicle is raised, locate the tank mounts. Most tanks use straps, but some have bolt-in flanges. To support the bottom of the tank while removing the tank mounts, use a small floor jack with a wide block of wood.

Now, you can begin to disconnect the various components connected to the fuel tank. Start by removing the filler cap and any ground straps, bolts, or screws inside the filler door. Depending on your vehicle, you may be able to disconnect the filler hose under the truck, but some models have steel filler necks that are not removable.

At this point, you can slowly lower the jack, exposing the pump mount, wiring, and hoses. Before proceeding, ensure that you are wearing safety goggles and that you are working in a well-ventilated area, free from any heat sources, sparks, and open flames. Do not smoke while working around fuel sources.

Remove the fuel filler neck

Removing the fuel filler neck is a crucial step in replacing the fuel pump on a Chevy truck. This step can be a little challenging due to the location of the fuel filler neck. Here is a detailed guide on how to remove the fuel filler neck:

Locate the Fuel Filler Neck

The fuel filler neck is on the driver's side of the fuel tank and above the frame. It is a large-diameter hose connected to the tank with a hose clamp. Before attempting any repairs, ensure the engine is off and the keys are removed from the ignition. It is also recommended to disconnect the ground cable from the battery as a safety precaution.

Loosen the Hose Clamp

Use a stubby flat-head screwdriver to loosen the hose clamp that secures the fuel filler neck to the tank. Be gentle to avoid damaging the hose or the tank.

Once the hose clamp is loose, carefully pull the fuel filler neck away from the tank. It should come off fairly easily. Set it aside in a safe place, as you will need to reattach it later.

Prepare for Fuel Spill

Be prepared for a fuel spill when removing the fuel filler neck, as there may still be some fuel left in the lines. Have a suitable container and absorbent rags ready to catch any spilled fuel. It is important to work in a well-ventilated area and avoid any sources of ignition or open flames during this process.

Protect Your Eyes

Always wear safety goggles when working with fuel systems to protect your eyes from any fuel splashes or sprays.

Disconnect the Fuel Lines

After removing the fuel filler neck, move to the passenger side of the tank and disconnect all the lines connected to the top of the tank. Start with the vapor line and then move on to the larger supply line. These lines have similar connectors that you can squeeze at the base to release. Be prepared for more fuel to spill during this step.

By following these steps, you will be able to successfully remove the fuel filler neck, providing access to the fuel pump for replacement. Remember to work carefully and safely when dealing with fuel to avoid any accidents or injuries.

Disconnect the fuel tank lines

To disconnect the fuel tank lines of your Chevy truck, you'll need to first relieve the pressure within the fuel system. Open the gas cap on the side, remove the fuel pump relay from the fuse box, then start the engine and let it run until it stalls.

Next, you'll need to raise the rear end of the truck on jack stands and block the front wheels. Use an Allen wrench to remove the screws mounting the flange for the door to the gas cap. Disconnect and remove the shield over the tank and the filler pipe's ground strap.

Now, you can disconnect the fuel supply and return lines. Press the retaining tabs for plastic quick-connect fittings, while using a fuel line separator tool for metal collar fittings. Be prepared for a lot of gas to spill from the lines as there will still be some pressure left. Make sure you wear safety goggles to protect your eyes.

If your Chevy truck has an EVAP canister, you'll need to disconnect the hoses from the canister and remove the bracket mounting bolt.

Frequently asked questions