How To Troubleshoot And Replace Chainsaw Fuel Lines

If your chainsaw is not performing at its finest, bad or broken fuel lines can often be the culprit. All you need are a few basic tools to remove and replace the wonky lines in your workhorse and return the brattle to your chainsaw. It shouldn't take more than 30 minutes to get the brattle back in your saw.

chainsaw in the garden on the block
credit: igorirge/iStock/GettyImages
How To Troubleshoot And Replace Chainsaw Fuel Lines

How to Test Fuel Lines

If the odor of gas hangs heavy in the air more than usual when you rev up your chainsaw, it could be a clogged or broken fuel line. These can crack or break with heavy use or wear out and become brittle if not protected from the elements. If the smell of gas is overwhelming and/or you see gas seep from the body, turn off the machine immediately as it could cause a fire.

If you haven't used the saw in some time, check the fuel lines first as a precaution.You can do this by dunking the fuel lines in water once you have removed them from the casing. Or, block off one end of the line, place a pressure gauge on the other end and fill it with air. Spray with soapy water to see if it bubbles. If you see bubbles, you know you have a leak and the line needs replacing.

How to Replace Fuel Lines

You'll need an Allen wrench, socket driver, needle-nose pliers, fuel container that is made for gas, scissors, protective gloves and shop rags to get started.

Drain the fuel tank into a container specifically meant for gas in a well-ventilated area. Remove the cylinder shield by removing the screws with the Allen wrench and disconnect the wire from the spark plug. Take the cover off the air filter housing and carefully pull out the filter so you can reuse it if it's not clogged. Unscrew the mounting nuts to the carburetor with a socket wrench to expose the engine. Be careful not to damage or twist the throttle link or exposed gas lines. Use the needle-nose pliers to pull the lines out of the gas tank with some caution. To put the new lines in, cut them at an angle with scissors and thread them onto the fuel tank. A drop of oil on the lines will help you push stubborn lines securely into the tank. Begin the process to return all the parts to their original fittings making sure to tighten as you go.

Kimberley McGee

Kimberley McGee

Kimberley McGee is an award-winning journalist with 20+ years of experience writing for a variety of clients, including The New York Times, Las Vegas Review-Journal Home section and other national publications. As a professional writer she has researched, interviewed sources and written about home improvement, interior design and related business trends. She earned a B.A. in Journalism from the University of Nevada, Las Vegas. Her full bio and clips can be viewed at