Craftsman lawn mowers are sold by Sears department stores. The Craftsman 22-inch mower is a walk-behind unit that is powered by a small gasoline engine which is operated by a pull starter. The single cutting blade is durable but will wear over time, so you must remove it to sharpen and eventually replace it.
Locate the spark plug on the side of the engine cylinder. Grasp the spark plug boot where it attached to the spark plug and pull it straight up to release it from the plug.
Tip the mower on its side with the carburetor and air filter assembly facing upwards, as this will keep fuel from leaking out of the mower.
Put on a pair of heavy work gloves. Hold the blade firmly with one hand. Place a socket that is attached to a ratchet wrench on the bolt at the center of the blade. Loosen and remove the bolt. Be careful not to loose the flat mounting plate, which may fall off once you remove the bolt.
Lift the blade straight off of the crankshaft and remove it from the cutting deck.
Slide the blade adapter straight off of the crankshaft. Apply a layer of light-weight motor oil to the crankshaft and the interior surface of the hole in the blade adapter with a finger. Slide the adapter back into place on the crankshaft.
Slide the center hole in a replacement blade over the crankshaft. Ensure the side of the blade that is embossed with the word “Bottom” is facing downwards. Push the mounting plate back over the crankshaft, ensuring that the tabs in the plate line up with the small holes in the blade. Thread the retaining bolt back into place at the center of the blade finger-tight.
Transfer the socket used to remove the blade retaining bolt from the ratchet wrench to a torque wrench. Place the socket over the bolt and tighten it to between 450- and 600-inch-pounds of torque.
Tip the mower back over onto its wheels. Push the spark plug boot back onto the end of the plug until it snaps into place.