Before you can sharpen or replace the blade on your Murray mower, you must remove the existing blade from the mower. You will need to drain the fuel from the gas tank prior to removing the blade. The mower will be sitting on its side and, if there is fuel in the tank, the fuel could spill on the ground or all over the engine. The Murray push mower blade secures to the mower with a single bolt. Because of heat expansion, this bolt will be tight. A scrap piece of wood is necessary to keep the blade steady while you remove it.
Empty the fuel tank in the Murray push mower. Consider two options for emptying the fuel tank. The safest and cleanest way to empty the mower fuel tank is to start the mower and allow it to run until it runs out of gas. You can also purchase a siphon hose at a home improvement center. The siphon hose has two tubes. One goes inside the fuel tank, and the other can go into a container. Use the bulb on top of the siphon hose to suck the fuel out of the tank and empty it into a container.
Grab the spark plug wire boot where the plug wire connects to the spark plug. Pull the boot off the spark plug, and bend the wire where it will not accidentally come in contact with the spark plug.
Lift the side of the mower that the gas tank is on, and set the mower on its side. Place a block of scrap wood between the blade and the mower deck. You want a thick enough piece of scrap wood that will keep the blade from moving while you are loosening the center bolt. Jam the wood under the blade or wedge the wood between the blade and the inside lip of the mower deck.
Remove the center bolt that secures the blade to the mower with a socket wrench. Pull the bolt away from the blade, and remove the three washers from the blade.
Hold the blade with one hand, and remove the piece of wood. Pull the Murray push mower blade off the mower.