How to Replace a Chainsaw Carburetor

 

chainsaw carburetor PD_0071_358_545070601

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.

Repair difficulty:
     
Time required:

Less than 30 min.

Parts required

  • Chainsaw carburetor

For manuals, repair guides, and specific part recommendations, enter your model number.

Tools Required

  • Allen wrench
  • 7/16" socket driver
  • Needle-nose pliers
  • Approved fuel container
  • Rags
  • Work gloves
  • Safety glasses

Before you begin

Wear work gloves to protect your hands.

Instructions

 Warning: Undertaking repairs to appliances can be hazardous. Use the proper tools and safety equipment noted in the guide and follow all instructions. Do not proceed until you are confident that you understand all of the steps and are capable of completing the repair. Some repairs should only be performed by a qualified technician.

Step 1: Drain the fuel tank

In a well-ventilated area, remove the fuel cap and the drain the tank into an approved storage container. 

Step 2: Remove the cylinder shield

Using an Allen wrench, remove the screws that hold the cylinder shield to the engine. Lift off the cylinder shield. 

Step 3: 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. 

Step 4: Remove the carburetor mounting nuts

Using a 7/16" socket, remove the two mounting nuts that secure the carburetor to the engine.  

Step 5: Detach the air filter housing

Pull the air filter housing off the carburetor.

Step 6: 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.

 Tip: For accurate reassembly, take digital photos of the throttle linkage on the carburetor and the gas line connections.

Step 7: Remove the carburetor

Disconnect the throttle linkage. Pull the carburetor completely off the mounting studs. Check the mounting gasket and replace it if necessary.

Step 8: Install the new carburetor

Connect the throttle linkage on the new carburetor. Slide the new carburetor onto the mounting studs. Connect the fuel lines.

Step 9: 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

Step 10: 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.

Step 11: Reinstall the cylinder shield

Reinstall the cylinder shield on the chainsaw. Refill the fuel tank.