This DIY chainsaw repair guide explains how to replace a chainsaw carburetor. The carburetor mixes air and gas, which ignites in the cylinder to power the engine. If the engine won’t start when the tank is full of fresh fuel, test the carburetor by removing the air filter and pouring about a teaspoon of fuel into the carburetor. Pull the starter rope. If the engine starts and then quickly dies, the carburetor is likely the problem. Replace the carburetor using the manufacturer-approved replacement part.
Use these steps to replace the carburetor in Craftsman, Poulan, McCulloch, Snapper, Husqvarna, Troybilt and MTD chainsaws.
If you prefer rebuilding the carburetor, How to Rebuild a Chainsaw Carburetor shows how.
Drain the fuel tank
In a well-ventilated area, remove the fuel cap and the drain the tank into an approved storage container.
Open the fuel cap.
Remove the cylinder shield
Using an Allen wrench, remove the screws that hold the cylinder shield to the engine. Lift off the cylinder shield.
Remove the screws that hold the cylinder shield.
Remove the cylinder shield.
Disconnect the spark plug wire and remove the air filter
Disconnect the wire from the spark plug. Pull the cover off the air filter housing and remove the filter.
Disconnect the spark plug wire.
Remove the air filter cover.
Remove the air filter.
Remove the carburetor mounting nuts
Using a 7/16-inch socket, remove the two mounting nuts that secure the carburetor to the engine.
Remove the mounting nuts.
Detach the air filter housing
Pull the air filter housing off the carburetor.
Remove the air filter housing.
Disconnect the fuel lines
Pull the carburetor away from the engine block. Be careful not to bend the throttle linkage or damage the gas lines. Use needle-nose pliers to detach the gas lines from the carburetor.
Carefully pull the carburetor forward on the mounting studs
Pull the fuel lines off of the carburetor.
Remove the carburetor
Disconnect the throttle linkage. Pull the carburetor completely off the mounting studs. Check the mounting gasket and replace it if necessary.
Pull the carburetor off the mounting studs.
Install the new carburetor
Connect the throttle linkage on the new carburetor. Slide the new carburetor onto the mounting studs. Connect the fuel lines.
Fasten the carburetor in place
Slip the carburetor onto the mounting studs and push it into place. Position the air filter housing on the protruding studs.
Replace the mounting nuts and tighten them to seal the gasket between the engine and the carburetor.
Reinstall the air filter cover and connect the spark plug
Position the air filter on the housing and replace the cover. Reattach the spark plug wire.
Reinstall the cylinder shield
Reinstall the cylinder shield on the chainsaw. Refill the fuel tank.
If the engine won't start even though there's fuel in the chainsaw, the carburetor could be the problem. Sometimes, it's easier to replace the carburetor than to clean it and rebuild it. Follow these steps to do the job yourself in about half an hour.
If your chainsaw isn't running well, a dirty carburetor could be the problem. You can take it apart, clean it and rebuild it, using a carburetor rebuild kit. This repair guide takes you through the process.
These tips may help you get your hard-to-start chainsaw running.
Put away your chainsaw the right way so it's ready the next time you need firewood.