Replacing Your Harley's Fuel Line: A Step-By-Step Guide

Changing the fuel line on a Harley-Davidson motorcycle is a task that many owners may need to do at some point. There are various reasons why you might need to change your fuel line, from routine maintenance to fixing a leak. This process can be done at home with basic tools, and there are many online tutorials and forum discussions offering advice on how to do it. However, it is important to be careful when removing and replacing the fuel line, as complications can arise if the threading is not done correctly.

Removing the fuel tank

To remove the fuel tank on a Harley-Davidson motorcycle, you will need to first drain the tank. Siphon most of the gas out of the top of the tank and place rags underneath the crossover.

Then, to access the fuel lines, you will need to remove the tank cover. There is a silver cover under the tank with a couple of plugs, wires, and around 10 torx screws holding it in place. Once these are removed, you can access the fuel lines and the pump.

The next step is to release the end of the fuel line and unscrew the quick connect from under the tank. Be careful when unscrewing, as the threads do not go in perfectly straight, and it is easy to mess up the threads. Place a rag underneath when unthreading to catch any remaining fuel.

Finally, to completely remove the tank, you will need to disconnect the fuel lines at the throttle body. Make sure to have replacements for the o-rings and c-clips on hand, as these can fly off and are essential for sealing the fuel system.

Disconnecting the fuel line

First, locate the fuel lines. You will need to remove the fuel tank to access them. Place a rag underneath the fuel lines to catch any spills or drips. Next, turn the hex section to the left on both lines. Be cautious when performing this step, as the upper hexes are hollow, and the steel lines pass through them, sealing into check valves at the bottom of the tank. After turning the hex, pull the crossover line off the front of the tank. This step can be a bit messy, so be prepared with extra rags.

Now, we will focus on the quick disconnect valve. This is where the fuel line attaches to the tank. You may need to drain the fuel tank before proceeding, especially if you notice any leaks. Once the tank is drained, you can release the end of the fuel line from the quick disconnect valve. Be careful when handling the valve, as it may have sharp edges. You may need a rebuild kit and some pick tools to remove the valve effectively. Pay attention to the O-rings inside the valve, as they tend to dry out over time due to ethanol fuels. Replace them if necessary.

If you are having trouble removing the fuel line, you can try unscrewing it at the hex section. Be very careful not to cross-thread the lines, as this can lead to complications. It is important to note that the lines do not thread perfectly straight, so do not force them. If you are replacing the fuel lines, it is recommended to use high-quality replacements such as those from Goodridge. Their fuel lines are known to be of good quality, and they cost about half the price of the original Harley lines.

Finally, when you are ready to reconnect the new fuel line, be sure to have new O-rings and C-clips on hand, as the old ones may not be reusable. The C-clips, in particular, can fly off and disappear, so it is important to be prepared with replacements. Ensure that the new fuel line is securely connected to the quick disconnect valve, and then you can reattach the fuel tank and tighten any necessary screws or bolts.

By following these steps, you can successfully disconnect and replace the fuel line on your Harley. Remember to take your time, work in a well-ventilated area, and always put your safety first when working with fuel.

Replacing the o-rings

When replacing the o-rings on your Harley, it is important to take your time and be careful not to cross-thread the o-rings. Here is a step-by-step guide on how to replace the o-rings on your Harley's fuel line:

First, you will need to gather the necessary tools and materials. These include a new o-ring, a dental pick with a 90-degree turn at the end, a mirror, a light source, silicone spray or WD-40, and some rags. You may also want to place a rag underneath the fuel line to catch any drips or spills.

Next, locate the fuel line and identify the male and female ends of the connection. The male end is usually the end that inserts into the female end, which has a groove or check valve where the o-ring sits. Using your dental pick, carefully remove the old o-ring from the groove. Take note of its size and shape so that you can match it with the new one.

Once the old o-ring is removed, inspect the groove for any debris or damage. Use your mirror and light source to get a better view if needed. It is important that the groove is clean and free of any debris before installing the new o-ring.

Now, take your new o-ring and lightly lubricate it with silicone spray or WD-40. This will help it slide into the groove easily and prevent it from getting stuck. Make sure the o-ring is the correct size and sits securely in the groove.

Finally, reconnect the fuel line, being careful not to cross-thread it. Hand-tighten the connection first, and then use the appropriate tool to tighten it further if necessary. Do not overtighten, as this can damage the threads and the new o-ring.

By following these steps, you can replace the o-rings on your Harley's fuel line, ensuring a secure and leak-free connection. It is recommended to have spare o-rings on hand in case of any damage during the replacement process.

Draining the tank

To drain the tank of your Harley, you will need to siphon most of the gas out of the top of the tank. Place rags under the crossover and the bike's left side. Then, clamp the right end of the crossover and remove that side. Quickly place a drain hose on the now open nipple, and lean the bike to the right to complete the process.

It is important to note that you cannot drain the tank through the set screw on the left line as this is where the fuel pressure is checked. The plug in the bottom of the line is the port for this. Additionally, be cautious when removing the fuel lines by turning the hex section to the left on both lines, as the upper hexes are hollow and the steel lines pass through them, sealing into check valves at the bottom of the tank.

If you are experiencing leaks in your fuel line, it could be due to worn O-rings, which typically last about eight years with ethanol fuels drying them out. You can fix this by replacing the O-rings or the entire check valve. This is a relatively easy and quick fix that can be done without removing the tank. However, if you are uncomfortable performing the repair yourself, you can take your bike to a dealership or mechanic, although this may be more expensive.

Before attempting any repairs or maintenance on your Harley, make sure to consult the MoCo Service Manual and The Parts Book for detailed instructions and diagrams. These resources can guide you through the process of changing your fuel line and addressing any leaks or issues you may be experiencing.

Re-threading the fuel line

• Place a rag underneath the fuel line to catch any spills or leaks.
• Identify the hex section on the fuel line. Turn the hex section to the left to loosen the connection. The upper hexes are hollow, and the steel lines pass through them, sealing into check valves at the bottom of the tank.
• When re-threading, be mindful that the lines do not thread perfectly straight. They go in at a slight angle, so take your time and be gentle to avoid any complications.
• Do not force the re-threading. If you encounter resistance, stop and re-evaluate.
• Make sure to have replacements for the O-rings and C-clips. These small parts can fly off and disappear, so it's a good idea to have spares on hand.
• Once the new fuel line is in place, gently tighten the connection by turning the hex section to the right.
• Check for any leaks and ensure that the fuel line is securely connected.

It is important to note that if your Harley is a 2007 FXD, you may need to remove the tank cover and the silver cover underneath to access the fuel line and quick disconnect. Additionally, if you are working on an EFI Harley, you may need to drain the tank and remove the fuel pump, regulator, filter, and float assembly for easier access to the fuel line.

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