Replacing Fuel Injectors: A Step-By-Step Guide For Yz450 Owners

If you're looking to replace the fuel injector on your Yamaha YZ450, you're in the right place. This is a job that can be done at home with the right tools and parts, and it's a great way to improve the performance of your bike. In this article, we'll take you through the step-by-step process of replacing your fuel injector, from removing the fuel tank to making the necessary connections and sealing the deal. We'll also explore the benefits of replacing your old or broken fuel injector, including improved horsepower and fuel efficiency. So, whether you're a motocross racer or a casual rider, read on to learn how to replace the fuel injector on your Yamaha YZ450 and get back to riding in no time!

Remove the fuel tank and mark the fuel pump's orientation

To remove the fuel tank from your Yamaha YZ450 dirt bike, you'll first need to extract the fuel from the tank through the fuel tank cap. Be careful not to damage the fuel pump coupler when doing so. Even after removing the fuel, be cautious when handling the fuel hoses, as there may still be some fuel remaining. Before disconnecting the fuel hose, clean the area around it and place a few rags underneath to catch any spillages.

To disconnect the fuel hose from the fuel tank, first, remove the fuel hose connector holder, then slide the fuel hose connector cover. Next, slide the fuel hose connector cover in the direction of the arrow mark and press the buttons on both sides of the connector to release it. You can disconnect the hose by hand, without the use of tools.

To prevent sand, dust, and other foreign materials from entering the fuel pump, install the included fuel hose joint cover onto the fuel pump and the disconnected fuel hose. When setting the fuel tank down, ensure that the installation surface of the fuel pump is not directly under the tank.

Now that the fuel tank has been removed, you can mark the orientation of the fuel pump so that you can reinstall it in the same position later.

Unscrew the Allen bolts and remove the fuel pump gasket

To replace the fuel injector on a Yamaha YZ450 dirt bike, you'll first need to remove the fuel tank from the bike. Mark the orientation of the fuel pump so you can put it back in the same position.

Now, for the Allen bolts. There are six 4mm Allen bolts that hold the fuel pump gasket in place. Unscrew these carefully and methodically, ensuring you don't misplace them. Once all six bolts are removed, you can then take out the gasket and the fuel pump from the tank.

It's important to note that if your fuel pump assembly has been damaged, you'll need to replace it. In the case of a crash, for example, the assembly may have taken a hard hit and could have pieces broken off.

Now that the gasket is exposed, you can remove it. Take your time with this step, being careful not to damage any other components. The gasket is crucial for creating a tight seal, so it's important to handle it with care.

With the gasket removed, you can now access the fuel pump and begin the process of replacing it with a new one.

Install the new fuel pump with a new O-ring

To install the new fuel pump with a new O-ring, first, get the new fuel pump and install the O-ring that seals the pump to the bottom of the tank. The O-ring has a flat edge that should be facing down and a beveled edge that should be facing up if you're holding the pump upside down when installing it. It is recommended that you install a brand new O-ring instead of reusing the O-ring from the old pump.

Before inserting the new fuel pump into the tank, make sure that the O-ring is seated properly. Use the marks made in Step 1 to line up the fuel pump, then install the gasket and the 4mm Allen bolts over it and tighten them down.

Now, connect the tank to the fuel line before reinstalling it. You won't have enough room to make the connection otherwise. To do this, pull the red section at the fuel line back, then make the connection as you're bringing the tank in. Push the tank all the way down and then push the red section in to lock it.

Finally, slide the fuel tank back into position at the front, which has two little sections protruding out on either side that lock it into place.

Re-insert the fuel pump and gasket, tightening the Allen bolts

To re-insert the fuel pump and gasket, and tighten the Allen bolts, follow these steps:

First, make sure you have the correct size Allen wrench for your bolts. Allen wrenches are also known as hex keys and are used for driving bolts and screws with hexagonal sockets. You can purchase a set of hex wrenches inexpensively at any hardware store.

Next, re-insert the fuel pump into the tank, ensuring the O-ring is seated down properly. Use the marks you made earlier to line up the fuel pump correctly. Then, install the gasket and place the 4mm Allen bolts over it.

Now, carefully insert the tip of your Allen wrench into the hexagonal cross section of the bolt. Turn the wrench in a clockwise direction to tighten the bolt. Repeat this process for all six 4mm Allen bolts, ensuring they are sufficiently tightened.

By following these steps, you will have successfully re-inserted the fuel pump and gasket, and tightened the Allen bolts on your YZ450.

Reconnect the fuel tank to the fuel line and its electrical connection

To reconnect the fuel tank to the fuel line and its electrical connection, follow these steps:

Firstly, connect the tank to the fuel line. Pull the red section at the fuel line back and make the connection as you bring the tank in. Push the tank all the way down and then push the red section in to lock it.

Next, slide the fuel tank back into position at the front. There are two small sections protruding out on either side that will lock the tank into place.

Now, connect the fuel tank to its electrical connection. There is a single plug underneath the tank that you need to push in until you hear a click.

Finally, reinstall the bolt at the back that holds the fuel tank in place. Ensure it is secure and you have completed the fuel tank reconnection process.

It is important to note that these steps are specific to the Yamaha YZ450 dirt bike and may not apply to other motorcycle models.

Frequently asked questions