Starting a Stihl MS 250 correctly is the foundation for efficient cutting and long-term reliability. This lightweight yet powerful chainsaw is a favorite among homeowners and professionals alike, but performance depends entirely on proper startup procedure. Following the correct steps ensures the engine fires smoothly, reducing wear on critical components.
Preparing the MS 250 for Startup
Before you pull the starter cord, preparation is essential for a safe and successful start. Taking a moment to check the basics prevents frustrating pull-starts and potential accidents in the field.
Place the saw on a flat, stable surface with the chain pointing away from your body.
Ensure the area is clear of debris, fuel, and obstacles to prevent entanglement.
Engage the chain brake by pushing the hand guard forward until it locks.
Confirm the fuel tank is adequately filled with mixed gasoline and two-stroke oil.
Check that the air filter is clean and properly seated for optimal air flow.
Setting the Correct Starting Position
The physical stance of the saw dictates the ease of the pull and the safety of the operator. A stable grip prevents the tool from moving unexpectedly during the critical first pull.
Priming the Engine
Cold engines require a specific fuel mixture to ignite efficiently. The primer bulb, located near the air filter, prepares the carburetor by injecting fuel directly into the system.
Locate the small rubber bulb on the side of the engine and press it firmly several times until the rubber feels firm and resistant. You should see fuel visible in the clear window of the carbureor, indicating the line is primed. Skipping this step often results in a difficult, prolonged pull that can flood the engine.
Engaging the Choke
The choke restricts air intake to create a rich fuel mixture necessary for a cold start. Identifying the choke lever is the next critical step before pulling the cord.
Locate the choke lever, typically positioned below the handle. Move the lever to the "Closed" or "Choke" position, usually marked by a symbol resembling a butterfly or the word "COLD." This setting ensures the engine receives the concentrated fuel mix needed to start. Once the engine warms, remember to open it to the "Run" position for normal operation.
Starting the Engine
With the saw positioned, primed, and choked, you are ready to initiate the starting sequence. The motion should be smooth and decisive to generate the compression needed for ignition.
Lift the saw slightly to ensure the chain is not touching any surface. Firmly grasp the starter rope and pull it out smoothly. Do not yank it violently, as this can damage the recoil mechanism. If the engine does not fire immediately, return the rope to the full length and pull again. The engine should cough, sputter, and then fire up with a distinct rotation sound. Immediately release the rope once the engine runs to prevent injury.
Warming and Finalizing
A successful start is only the first step; allowing the engine to stabilize ensures smooth operation and prevents stalling during work.
