How to Install the Fuel Line in the Gas Tank of a String Trimmer

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When something goes wrong with your string trimmer (also known as a weed trimmer or weed whacker), it can be tempting to just toss it and buy a new one. First of all, that's a waste of money. Second, that's bad for the environment. Reuse is the key to a healthy planet and a healthy budget. The next time the fuel line on your string trimmer stops working, first try fixing it yourself before replacing the trimmer.


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How the Fuel Lines Work

It's common for fuel lines on your string trimmer to degrade over time and break. Even durable fuel lines can dry up, crack, or be punctured. Both the small fuel line and the large fuel line can be replaced even by a novice.

How do these fuel lines work? Think of a heart. One side pumps blood in and one side pumps blood out, to put it simply. Both fuel lines on a string trimmer work in a similar manner. The small fuel line suctions gas into your carburetor from the gas tank. The large fuel line returns any excess or unused gas back into the gas tank.


Remember to put safety first anytime you work with a string trimmer. Make sure to put on gloves and safety goggles before you get started.

Replacing String Trimmer Fuel Lines

First, remove the spark plug wire from the spark plug. Keep the wire at a distance so that it cannot make any contact with the spark plug. Next, pour the gas from the string trimmer's fuel tank into a gas can. Use a funnel to prevent spills. Using a pair of needle-nose pliers, pull the two fuel lines off the carburetor. If oil spills during this step, wipe it away with a cloth before you continue. Check the ground before continuing to make sure that there's no oil that makes you trip or slide.


Locate the two screws on the gas tank and remove them and then remove the gas tank from the string trimmer. Now that the gas tank is removed, you should be able to easily remove the two gas lines. Do this slowly and carefully.

Discard the damaged fuel line in the trash and replace it with a new one. You can purchase new fuel lines at your local hardware store or online for your string trimmer's model. Make sure that fuel lines you use are compatible with your model — installing fuel lines that are the wrong size or incompatible with your model will likely lead to problems.


Next, insert the other end of the new fuel line into the gas tank. Put the line into the same hole from which you removed the damaged one.

Push the new line through the small hole and out the large hole to the lid for the gas tank. You may need the help of the needle-nose pliers again for this task. Reattach the gas tank to the string trimmer, then the fuel lines to the carburetor. Last, reattach the spark plug wire.


Testing Your String Trimmer

It's time to take your repaired string trimmer for a test drive.

Before starting up your string trimmer, make sure you're using it safely. Always wear protective clothing, including long pants, long sleeves and closed-toe shoes when using a string trimmer. Check to make sure you've followed the fuel line replacement steps correctly before attempting to start the trimmer.


If you followed all of the steps correctly, it should work like a charm. If not, it may be time to ask an expert for help or purchase a new string trimmer or an alternative.



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