Things You'll Need
Spark plug socket
Spark plug gapping tool
The Toro brand includes a variety of gasoline-engine-powered lawn mowers. In such a powerplant, gas and air combine in the combustion chamber, and a spark plug provides combustion when the cylinder compresses the air and gas. Toro recommends replacing your mower' spark plug at the start of every grass cutting season or after every 200 hours of operation. Changing the plug is a simple process you can do yourself rather than haul the mower to a repair shop. The plug must be gapped properly for reliable performance. Check the engine specifications on your particular model to determine the proper gap, which varies with the Toro model.
Pull off the metal loop on the tip of the spark plug to disconnect the engine wire.
Slip the spark plug socket over the end of the plug. A 5/8-inch socket is common but not universal. Test different sockets on the plug until you find the one that fits snug.
Twist the socket with a socket wrench counterclockwise to remove the old plug.
Use the gap tool to bend the spark plug's L-shaped wire to the gap recommended for your Toro engine. A gap of 0.03 inches (0.76mm) is common for small engines but not universal. Check the engine block on the Toro for the gap recommendation or review the manual that came with the engine.
Insert the gapped end of the plug into the socket on the engine and turn clockwise with the socket wrench until the plug is snug.
Slip the metal loop attached to the engine wire over the tip of the new spark plug.