When your mower is down and out, run through this quick checklist before heading to the mechanic.
Step 1: Check the spark plug. Pull the rubber spark plug wire up and off the plug. Remove the plug by turning it counter clock wise. If the plug is encrusted with carbon buildup or the mower is having trouble starting, replace the plug with a new one. Otherwise, wipe the plug off with a soft cloth and re-install it. Keep the rubber spark plug wire detached while working on the mower.
Step 2: Check the air filter. Remove the cover above the filter and take out the filter. If the filter is made of foam, rinse it with warm, soapy water or gasoline. Allow it to dry completely before replacing it. If the filter is paper, use a vacuum or air compressor to clean it or knock it hard against the ground to loosen the excess dirt within the pleats. If the filter seems worn or irreversibly dirty, replace it with a new one.
Step 3: Check the oil every time the mower is used. Drain and change the oil at least once a year. If the mower has an oil drain plug, place the mower up on cinder blocks. Locate the oil drain plug beneath the blade area. Place a drain pan under the mower and use a standard 3/8-inch ratchet, without a socket on it, to loosen the plug. Once the oil has drained completely, replace the drain plug and refill the oil reservoir with 20 ounces of SAE 30W oil.
Step 4: Sharpen the blade. Tip the mower backward and use a box end or open end wrench to remove the blade. Use a flat bastard file to sharpen along the cutting bevels, making smooth, even strokes on both sides of the blade to maintain its balance. Better yet, take the blade to your local hardware store or tool shop to have it professionally sharpened. If the blade is nicked, bent or worn, replace it with a new one.
Step 5: Check the gas. If you forgot to drain the gas tank before storing the mower for the winter, it will need to be drained. Use a hand pump or disconnect the fuel line to remove the old gas. Transfer the gas into a disposable plastic container. Reattach the fuel line if necessary and fill the tank with fresh, clean gas. If gas has been stored in a can over the winter chances are it will no longer be good. Bad gas can clog the fuel line and gum up the carburetor. Adding gas stabilizer to both the tank and can before winter will prevent the problem.
If the mower is still acting up after following these steps, a mechanic or a new mower may be the best option.
— Have a question? Email Linda Cottin at firstname.lastname@example.org.