Replacing Fuel Injectors On Your Harley: A Step-By-Step Guide

Replacing the fuel injectors on a Harley-Davidson motorcycle can be a complex task. While some people choose to do it themselves, others prefer to seek professional help. There are a variety of reasons why one might need to replace their fuel injectors, such as experiencing issues with the bike's performance or receiving error codes. Before replacing the injectors, it is important to correctly diagnose the problem, as the issue might lie elsewhere, such as with the spark plugs or ignition wires. If one chooses to replace the fuel injectors themselves, it is important to follow the official factory procedure or seek guidance from a trusted mechanic or forum.

Disconnect the feed line

Disconnecting the feed line is the first step in removing and replacing the fuel injectors on a Harley-Davidson motorcycle. This is a delicate process and should be done with care to avoid any leaks or damage to the fuel system.

Firstly, locate the feed line on the left side of the motorcycle. This is the line that supplies fuel to the injectors, so it is important to make sure that the fuel supply is turned off before disconnecting the line. Once you have located the feed line, place a drain pan or container underneath it to catch any fuel that may spill during the disconnection process.

To disconnect the feed line, you will need to remove the quick-connect fitting that secures the line to the injectors. This can be done by using a quick-connect release tool or a pair of needle-nose pliers. Gently insert the tool or pliers into the quick-connect fitting and depress the locking tab while pulling the feed line away from the injectors. Be careful not to damage the locking tab or the O-ring seal inside the fitting, as this could cause leaks when the line is reconnected.

Once the feed line is disconnected, it is important to plug or cap the open end to prevent any fuel spillage or contamination. You can use a piece of tape or a suitable plug to secure the end of the line. Additionally, make sure to clean the area around the injectors to remove any dirt or debris that may have accumulated. This will help ensure that no contaminants enter the fuel system during the injector replacement process.

After the feed line has been successfully disconnected and secured, you can proceed with removing the fuel injectors. This process will involve disassembling the throttle body and carefully removing the injectors as a unit. It is important to work in a clean environment and to handle the injectors with care to avoid any damage.

Lift the rear of the tank

To replace the fuel injectors on a Harley-Davidson motorcycle, one of the first steps involves lifting the rear of the tank. Here is a detailed guide on how to safely and effectively lift the rear of the tank:

Step 1: Prepare the Motorcycle

Before attempting to lift the rear of the tank, it is important to ensure that the motorcycle is securely parked on a flat, stable surface. Engage the side stand and ensure that the motorcycle is in gear to prevent accidental rolling.

Step 2: Access the Fuel Tank

Locate the fuel tank and identify the rear section that needs to be lifted. The fuel tank is typically located under the seat or between the handlebars and the seat, depending on the Harley-Davidson model. Remove the seat and any necessary fairings or covers to access the fuel tank. Place the removed parts in a safe location to avoid misplacing them.

Step 3: Disconnect the Fuel Lines

Before lifting the rear of the fuel tank, it is crucial to disconnect the fuel lines safely. Locate the fuel line quick-disconnect fittings, which should be near the fuel tank. Depress the tabs on the fittings and gently pull the fuel lines away from the tank. Be prepared to catch any residual fuel with a clean cloth or drip tray to avoid spills.

Step 4: Lift the Rear of the Tank

Now, focus on lifting the rear of the tank. Gently tilt the tank towards the front of the motorcycle to access the fuel injectors. Lift the tank slowly and with control to avoid putting strain on the fuel lines and other connections. Use one hand to support the tank from below and the other hand to gently lift the rear end. Ensure that the fuel lines remain unobstructed and are not stretched or twisted.

Step 5: Secure the Tank in the Raised Position

Once the rear of the tank is lifted, temporarily secure it in this position. You can use a tank lift prop or a similar tool to hold the tank in place. Alternatively, carefully lean the tank against a stable object, such as a handlebar riser, ensuring it cannot accidentally fall or slip.

Step 6: Verify Clearance

Verify that you have sufficient clearance and access to the fuel injectors. Ensure that the fuel lines are not obstructing your work area and that all necessary components are within reach. If needed, adjust the position of the tank to ensure optimal access for the fuel injector replacement procedure.

By following these steps, you can safely and effectively lift the rear of the tank on your Harley-Davidson motorcycle, gaining the necessary access for fuel injector replacement. Remember to work slowly, maintain control, and ensure the security of the raised tank during the process.

Secure the tank with a piece of wood

"Secure the Tank with a Piece of Wood":

• Place a Piece of Wood: Lay a piece of wood, such as a 2x4 lumber, across the width of your motorcycle's frame, just behind the fuel tank. Ensure the wood is sturdy, straight, and longer than the width of the bike to provide a stable support system.
• Position and Stabilize: Adjust the wood so that it rests securely against the frame, providing a solid base to support the fuel tank. You may need to adjust the position to find the most stable point, ensuring the wood won't shift or move during the process.
• Cushioning: To protect the fuel tank and provide a softer contact point, wrap the area of the wood that will touch the tank with a soft cloth or cushioning material. This prevents scratching or damage to the tank's surface. Some people use an old towel or a piece of foam rubber for this purpose.
• Lift and Secure: With an assistant helping, carefully lift the fuel tank slightly and slide the wood securely underneath. Ensure the wood is positioned to support the weight of the tank and that it won't shift or move once the tank is released. You may need to adjust the height or position of the wood to find the most stable and secure fit.
• Double-Check Stability: Before proceeding, check the stability of the setup. Gently try to move the tank to ensure it is firmly supported and won't shift or wobble during your work. You can also try sitting on the bike (if safe to do so) to test the stability and ensure the tank won't move or shift under your weight.
• Work Safely: With the tank securely supported by the wood, you can now safely proceed with the fuel injector replacement process. This setup ensures that the fuel tank remains stable and secure, reducing the risk of accidental damage or injury during the repair work.

By following these steps, you can securely support the fuel tank, creating a safe and stable environment to work on the fuel injectors of your Harley-Davidson motorcycle. Remember always to take your time, work with an assistant if possible, and prioritize your safety and the protection of your bike during this process.

Spray silicone spray on both ends of the feed line

When replacing the fuel injectors on a Harley-Davidson, it is important to take note of the following step: spray silicone spray on both ends of the feed line. This is a crucial step in the process and should not be overlooked.

To begin, disconnect the feed line, also known as the "bong", on the left side of the motorcycle. You may need to lift the rear of the tank and place a piece of wood underneath to secure it in place. Once you have accessed the feed line, apply the silicone spray to both ends. This will help to create a seal and prevent any fuel leaks once the injectors are reassembled.

Make sure to use a quick-connect tool when reconnecting the feed line. This will ensure that the connection is secure and properly aligned. It is also important to work in a well-ventilated area when handling silicone spray and other chemicals.

By following these steps and taking the necessary precautions, you can effectively replace the fuel injectors on your Harley-Davidson and ensure a proper seal at the feed line connection.

Remove the throttle body

To remove the throttle body from your Harley-Davidson, you can follow these steps:

First, you don't need to remove the fuel tank. Disconnect the feed line (bong) on the left side, lift the rear of the tank and put a piece of wood underneath to support it. Spray silicone spray on both ends of the feed line quick connect before reconnecting it. This is important and will make the process easier.

Next, you don't need to remove the throttle body. Disconnect the injectors and remove the centre mounting screw. Pull the injectors out as a unit and then you can disassemble them on a workbench.

This is the process as described by a Harley-Davidson technician with over 25 years of experience.

Frequently asked questions