Weed Eater 21-inch push lawn mowers are designed for use by homeowners on small to medium-sized lawns. Created for simple operation, the mower features a single blade for cutting grass. Part of the routine maintenance associated with ownership of the mower includes removing the cutting blade for replacement or sharpening. It takes just a few basic steps and tools to accomplish this task.
Disconnect an electric Weed Eater push mower from the power source by unplugging the extension cord from the mower. Make a gasoline engine mower safe to work on by locating the spark plug wire on the front of the engine and pulling the boot from the tip of the spark plug.
Put on gloves to protect your hands from potential injury while working on the mower. Tilt the mower onto its side so you can access the cutting blade. Tilt an electric mower to either side. Tilt a gasoline engine mower so the gasoline tank is down toward the ground to prevent gasoline from running into the carburetor.
Place a block of wood against the mower housing. Turn the blade until it wedges against the wood and will not rotate further. Adjust the wrench so that it fits the nut that holds the blade on the mower spindle.
Loosen and remove the blade-retaining nut with the wrench, turning the nut counterclockwise. Remove the nut, square washer and insulator washer from the spindle, then remove the blade.
Place a new blade, or newly sharpened blade, on the spindle and make sure the trailing edge, or upward turned edge, is up toward the mower and not down toward the ground.
Hold the blade and place the insulator washer and square washer onto the spindle. Thread the nut onto the spindle and turn it clockwise by hand until snug. Place the block of wood back against the mower housing and turn the blade to wedge it in place. Tighten the nut in place with the adjustable wrench.
Lower the mower so that all four wheels are on the ground. Connect the spark plug wire back to the tip of the spark plug or return the plug on an electric model.