Replacing The Fuel Pump In A Fox Body Mustang

Replacing the fuel pump in a Fox Body Mustang is a rite of passage for Mustang ownership. The fuel pump is located inside the fuel tank, which makes the replacement process a little more challenging than simply removing a couple of bolts and swapping out the pump. The first step is to drain the fuel tank to around a quarter full or less. If your car is still running, drive it until it's almost out of gas. If the pump is non-functional, you will need to drain the fuel using a siphoning system. Once the tank is drained, remove the filler neck and vent tube, then disconnect the fuel lines and electrical connections. Lower the tank and remove the retaining bolts. From here, you can access the fuel pump and replace it with a new one.

Draining the tank

Before beginning work on your Fox Body Mustang, it's important to drain the fuel tank. This will make the tank lighter and easier to manoeuvre. If your car is still running, you can do this by driving it until the tank is almost empty. If your pump is non-functional, you will need to drain the fuel using a siphoning system, as there is no drain plug on the fuel tank.

It is recommended to have no more than a quarter of a tank of gas to make the removal of the tank easier. This will also keep the fuel level below the filler neck opening. If you are unable to drive the car, you will need to siphon the fuel out.

Safety is paramount when working with flammable materials. Always disconnect the battery and the fuel pump wiring at the rear bumper before beginning work. Keep any hot lights or open flames away from the work area to prevent an explosion or fire hazard. It is also recommended to wear safety goggles.

Once the fuel level is low enough, you can begin to remove the fuel tank. This will be easier with the filler neck loose, so remove the three mounting screws at the filler-neck opening to loosen the neck from the body of the car. There will be a small amount of fuel in the return line, so be ready with some shop rags.

Disconnecting the battery

Before beginning any work, ensure you have the correct safety equipment. This includes safety goggles to protect your eyes from any debris or sparks, and gloves to protect your hands. It is also recommended to work in a well-ventilated area to reduce the risk of inhaling fumes.

To disconnect the battery, locate the battery under the hood of the car. The battery is typically located near the front of the engine bay, on the driver's side. Once located, identify the negative cable. This will be a thick, black cable connected to the negative terminal of the battery, which is usually marked with a '-' symbol. Using a wrench or a socket, loosen the nut that secures the cable to the terminal. Do not allow the wrench to come into contact with any other metal parts of the car, as this could cause a spark. Once loosened, carefully remove the cable from the battery terminal. Ensure that the cable does not touch any metal parts of the car, as this could cause a short circuit. Place the cable in a safe location, away from the battery, to prevent accidental reconnection.

With the battery disconnected, you can now safely proceed with the rest of the fuel pump replacement procedure. Remember to exercise caution when working with flammable materials and always follow proper safety procedures.

Removing the retaining bolts

Before beginning, it is essential to ensure your safety and the stability of the vehicle. Wear safety goggles to protect your eyes from any debris or fuel spillage. It is also advisable to wear gloves to protect your hands. Place the car on jack stands to elevate it to a comfortable working height. This will provide you with better access to the fuel tank and its components. Ensure that the car is securely supported and will not shift or move during the process.

The first step is to locate the retaining bolts. These bolts are typically found on the inboard end of the tank straps, just aft of the axle housing. There should be two retaining bolts securing the fuel tank in place. To access these bolts, you may need to lower the tank slightly, especially if you have a larger jack or limited workspace. Use a jack to carefully lower the tank a few inches, just enough to provide the necessary clearance to reach the bolts.

Once you have located the retaining bolts, the next step is to remove them. Have a tray or container ready to place the bolts in a safe location once removed. Using the appropriate-sized socket or wrench, carefully loosen and remove the first bolt. Take your time with this process to avoid stripping the threads or damaging the bolt heads. With the first bolt removed, proceed to the second bolt and repeat the same process. Ensure that you do not drop the bolts into the undercarriage or engine bay, as retrieving them can be challenging.

With both retaining bolts removed, you can now focus on carefully lowering the fuel tank further. This step will provide you with access to the tank's fittings and hoses. Remember to support the tank with a jack or suitable support to prevent it from falling or placing undue stress on the filler neck. It is crucial to lower the tank slowly and with control to avoid any damage to surrounding components or injury to yourself.

Now that the tank is lowered, you can access the fuel pump assembly and proceed with the next steps in the replacement process. Remember to refer to a reputable repair manual or seek guidance from a professional mechanic if you are unsure about any aspect of the procedure. Safety should always be your top priority when working on automotive projects.

Disconnecting the hoses

Before beginning, ensure you have the necessary tools, including a floor jack or jack stands, safety goggles, a brass punch or brass hammer, ratchet straps, and a fuel line disconnect tool specific to Ford vehicles. It is also highly recommended to have no more than a quarter tank of gas to make the tank easier to handle and to prevent fuel spillage. If the pump is faulty and the car cannot be driven, siphon the fuel out manually.

Now, let's get started with the steps for disconnecting the hoses:

• Disconnect the battery and the fuel pump wiring at the rear bumper. This is an important safety precaution to prevent any accidental ignition during the process.
• Securely support the fuel tank using a floor jack or other means. This will provide stability and control when removing the hoses.
• Remove the two retaining bolts found on the inboard end of the tank straps, just aft of the axle housing. This will allow you to lower the tank and access the tank's fittings.
• You will now need to disconnect three hoses: the pressure and return hoses at the fuel pump and a push-on hose at the vapor vent valve. Be prepared for a small amount of fuel to leak from the return line. Use shop rags to catch any spillage and have a suitable container nearby.
• For the return line, you will need a Ford fuel line disconnect tool, which can be purchased at any parts store.
• Once all three hoses are disconnected, you can lower the tank further and slide it towards the driver's side. This will allow you to separate the fuel filler pipe from the tank's opening.

By following these steps, you will have successfully disconnected the hoses related to the fuel pump in your Fox Body Mustang. Remember to work carefully and always put safety first when dealing with flammable liquids and vehicle repairs.

Reinstalling the tank

• Ensure the tank is properly supported: Place a floor jack or jack stands under the fuel tank to support its weight. This will make it easier to manoeuvre and reinstall the tank.
• Connect the hoses: Reconnect the three hoses that were previously disconnected: the pressure and return hoses at the fuel pump and the push-on hose at the vapor vent valve. Be sure to use a Ford fuel line disconnect tool for the return line.
• Slide the tank back into place: With the hoses connected, carefully slide the tank back towards the driver's side, ensuring that the fuel filler pipe aligns with the tank's opening.
• Secure the tank: Once the tank is in the correct position, secure it using the retaining straps. Ensure that the straps are tight and that the tank is firmly in place.
• Reattach the fuel pump feed and return lines: Using the new fuel line retaining clip provided with the fuel pump kit, reinstall the fuel pump feed and return lines. This will ensure that the fuel can flow properly to and from the pump.
• Reinstall the fuel vapor vent line: In addition to the feed and return lines, the fuel vapor vent line must also be reconnected. This line helps to vent any vapours or gases that may build up in the fuel tank.
• Apply silicone spray lube to the fuel filler neck seal: Before reinstalling the tank, it is recommended to apply a generous amount of silicone spray lube to the fuel filler neck seal. This will create a tight seal and prevent any leaks.
• Slide the tank over the filler neck: With the lube applied, carefully slide the tank over the filler neck, ensuring that the filler neck fits snugly into the tank's opening.
• Test the installation: Once the tank is securely in place, test the installation by filling the tank with fuel and checking for any leaks or issues. Ensure that all connections are tight and secure before driving the vehicle.

It is important to note that working on a fuel system can be dangerous, especially when dealing with flammable materials. Always take the necessary safety precautions, such as wearing safety goggles and disconnecting the battery, to ensure a safe working environment.

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