Replacing Fuel Pump In Vt Commodore: Step-By-Step Guide

Changing a fuel pump in a VT Commodore is a complex process that requires careful attention to detail. To begin, one must remove the fuel tank to access the fuel pump. This involves supporting the tank, undoing the straps, and carefully lowering it to disconnect the wiring plug and fuel lines. It is important to use the correct tools, such as a special disconnect tool for the fuel lines, to avoid any damage. Additionally, taking photographs and consulting service repair manuals can be helpful. The process also requires addressing various hoses and clamps, and ensuring proper precautions are taken to avoid sparks or leaks when dealing with fuel.

How to Change a Fuel Pump in a VT Commodore

Removing the fuel tank

To remove the fuel tank from a VT Commodore, you will need to support the tank and undo the three straps; one of these has an earth wire. Lower the tank a little and disconnect the wiring plug to the pump, as well as the three fuel/return/vapour lines. You will need a special disconnect tool for this. You should also remove the breather from the filler neck.

It is sometimes easier to take the fuel cap off and then lower the whole tank from the car. Tap the retainer off and the pump should come out. You can get the correct disconnect tool from Repco (a set of two) for about $15.

It is recommended to run the car until the fuel light comes on and then a bit more. This is so you don't undo the tank straps and find a 50kg tank dropping your way. You should also take the fuel pump relay out and disconnect the battery, although this is just a precaution.

Using a hoist will make the job a lot easier. If you are using a hoist, use a bench or stand under the fuel tank when taking it out and putting it back in.

Disconnecting the wiring plug

Locate the Wiring Plug: Begin by identifying the wiring plug connected to the fuel pump. It should be accessible after lowering the fuel tank.

Support the Fuel Tank: Before proceeding, ensure that the fuel tank is securely supported. This will prevent any accidental drops or damage during the process.

Access the Wiring Plug: Lower the fuel tank slightly to gain better access to the wiring plug. This will provide the necessary space to work comfortably.

Identify the Connections: Carefully examine the wiring plug and identify all the connections. It is important to understand which wires are attached to the plug before attempting to disconnect it.

Disconnect the Wiring Plug: Using the appropriate tools, carefully disconnect the wiring plug from the fuel pump. Take your time with this step to avoid causing any damage to the wires or connectors. Ensure that you are only disconnecting the wiring plug and not any other components.

Secure the Wires: Once the wiring plug is disconnected, securely fasten or tie the wires to prevent them from dangling or getting in the way during the rest of the fuel pump replacement process.

It is important to work cautiously when dealing with electrical components such as wiring plugs. Always ensure that the car battery is disconnected before performing any work involving electrical systems. Additionally, having a basic understanding of automotive electrical systems or seeking guidance from a professional can help ensure a safe and successful wiring plug disconnection process.

Using a disconnect tool

When changing the fuel pump in a VT Commodore, you will need to disconnect the three fuel/return/vapour lines with a special disconnect tool. This is available from Repco for around $15.

The correct use of a fuel line disconnect tool is important to ensure that you do not cause any damage to the fuel system. Fuel lines have a lot of pressure, and using a fuel line disconnect tool helps you to disconnect the fuel line from the connector without causing any damage. The tools put the right amount of pressure on the connection to disconnect it with minimal effort. Many fuel lines can only be disconnected using a specialty tool. If you attempt to disconnect the line using other methods, you may cause damage to the system.

Fuel line disconnect tools are inexpensive and cost much less than replacing fuel lines that were damaged by incorrect removal. Before using the tool, be sure to wear safety goggles to protect your eyes from the damaging buildup, grease, grime, and dirt that may be present underneath your vehicle. All of that buildup can impede the tool from working properly, and you do not want any of it to make its way into the fuel lines, as it could work its way into the fuel pump and other parts of your engine.

To disconnect the fuel lines in your VT Commodore, locate the three fuel/return/vapour lines. Place the disconnect tool on the correct line and apply pressure to disconnect the line from the connector. Repeat this process for the remaining two lines.

Removing the retainer

Begin by locating the fuel pump assembly, which is situated within the fuel tank. To access the assembly, you will need to remove the rear seat of the vehicle. Once you have located the assembly, identify the retainer, which is a circular component that secures the fuel pump in place. The retainer will need to be carefully removed to access the fuel pump. Using the correct tools is essential for this process. You will need a retainer removal tool, which is designed specifically for this purpose. Place the removal tool onto the retainer and engage its claws or grips with the retainer's edges. Apply firm and steady pressure to the tool to slowly pry the retainer away from its seated position. It is important to be cautious and controlled during this step to avoid damaging any surrounding components or injuring yourself.

With the correct tool engaged, continue to apply steady force to slowly remove the retainer further. You may need to rock the removal tool gently from side to side to help dislodge the retainer, especially if it has been in place for a long time. Take care not to scratch or damage the fuel pump assembly or the surrounding fuel tank components during this process. Once the retainer has been pried up sufficiently, you can now lift and remove it completely. Set the retainer aside safely, ensuring it is placed in a secure location where it will not be lost or damaged. With the retainer removed, you will now have access to the fuel pump itself. You can proceed with the next steps, which involve carefully lifting and removing the fuel pump from the assembly.

It is important to work slowly and methodically during this entire process. If you encounter strong resistance or if the retainer does not seem to be releasing, do not force it. Instead, re-evaluate your technique, ensure you are using the correct tools, and consider seeking advice from a qualified mechanic. For safety, remember to work in a well-ventilated area and take the necessary precautions to avoid any potential ignition sources when working with the fuel system.

By following these detailed instructions, you can successfully and safely remove the retainer when changing the fuel pump in a VT Commodore. This will ensure you can access the fuel pump for replacement while minimizing the risk of damage to your vehicle and injury to yourself. Always refer to a professional mechanic's advice if you are unsure about any steps or procedures.

Using a hoist

First, run the car until the fuel light comes on, and then a bit more. You don't want to undo the tank straps only to have a 50kg tank drop on you. Next, remove the fuel pump relay and disconnect the battery.

Now, raise the vehicle on a hoist to a comfortable working height. Disconnect the earth wire from the tank securing clamp. Position a transmission jack under the tank to balance and support it. Undo the remaining fuel tank clamp bolts and remove the brackets. Slowly lower the jack to access the fuel lines, and disconnect them. Now, lower the jack all the way. With the help of another person, lift the tank off the jack and place it on the floor.

Mark the position of the sender unit on the tank before removing it. You will need the correct tool or an old nudge bar and hammer to tap free the locking ring around the fuel sender. Once the locking ring is free, lift up the sender unit and you will see the fuel pump connected to the sender unit. Depending on whether you feel the gauge might not be reading correctly, you can replace the sender and pump as one unit or just the pump.

To refit, just follow these steps in reverse.

Frequently asked questions