How to Unflood a STIHL Chain Saw

Stihl chain saws have a choke that makes cold starting easier, but you have to use it properly. When you close the choke, the carburetor sprays extra fuel into the combustion chamber when you pull the starter. If the engine doesn't start on the first three or four pulls, the fuel and air mixture becomes fuel rich, and if you continue to pull the starter while the choke is closed, there is too much fuel to ignite and the engine floods. You can simply wait for the fuel to drain, but there is a faster way to clear the engine.

  1. Set the chain saw on a level surface and make sure the chain break is activated. Pull the wire off the spark plug and remove the plug with a spark plug wrench. Check the electrodes and wipe them off with a rag if they are full of fuel.

  2. Unscrew the air filter cover and remove the air filter. Clean it if it's dirty.

  3. Set the master control lever to the minimum choke -- or open -- position. Pull the starting rope five or six times to clear fuel out of the combustion chamber.

  4. Replace the air filter and spark plug, and connect the spark plug wire. Leave the choke open and pull the starting cord several times. The chain saw should start.

  5. Things You Will Need

    • Gloves

    • Spark plug wrench

    • Rag


    When cold starting a Stihl chain saw, move the master control lever to the half-choke position after the fourth attempt to start it to avoid flooding the engine. Move the lever to the minimum choke position as soon as the saw starts.



    Wear gloves when handling a chain saw.

    Make sure the bar cover is removed before starting the saw.