A tune-up on you Honda mower consists of replacing the sparkplug, cleaning or replacing the air filter and changing the oil. Tune your mower at the beginning of each season. This will help ensure that you get optimal performance from your Honda mower year after year. Purchase sparkplugs, oil and replacement air filters at a home improvement center or auto parts store.
Place the mower on a level, flat surface. Turn the fuel valve to the off position if your Honda model uses a shutoff valve. The fuel valve is under the fuel tank. Turn the fuel valve counterclockwise to shut the valve.
Pull the sparkplug wire off the top of the spark plug. Some models require the you twist the sparkplug wire boot left or right slightly and pull the wire off the sparkplug.
Remove the sparkplug with a sparkplug socket or an appropriate-size socket wrench. Set the gap on the new sparkplug between .028 inch and .031 inch. To set the gap, place the gap tool between the insulator and the center electrode. Bend the tip of the center electrode up or down until you obtain the proper gap.
Insert the new sparkplug into the engine and tighten with the sparkplug wrench or appropriate-size socket wrench. Do not connect the sparkplug wire at this time. It is good safety practice to leave the spark disconnected while working on the mower.
Wipe the area around the oil fill neck with a clean cloth. The oil fill neck is on the opposite side of the engine across from the fuel tank. Place a container on the oil filler side of the mower to drain the old oil.
Remove the oil filler cap and wipe the dipstick clean with the cloth. The dipstick attaches to the bottom of the oil fill cap. Turn the mower on its right side to drain the oil through the oil fill neck into the container. When no more oil drains from the filler neck, place the mower back upright on its wheels.
Pour 1/2 qt. of 10W-30 motor oil into the engine through the oil fill neck. Place the dipstick inside the oil fill neck but do not screw it into the neck. Pull the dipstick out and check the oil level. A low point and high point on the dipstick indicate the oil level. You should be within those points. Place the dipstick into the fill neck and screw the cap into the fill neck threads.
Search for the air cleaner assembly in front of the fuel tank on the left side of the engine. Press down on the top of the air cleaner cover to disengage the retaining tabs. Pull the air cleaner cover away from the mower.
Pull the air cleaner filter out of the housing and inspect for damage. If it's damaged or the filter is dirty, replace the filter with a new one. Place the filter back into the housing and snap the air cleaner cover over the housing.
Connect the sparkplug wire to the sparkplug and push in until the wire snaps into place. Turn the fuel valve clockwise to allow fuel to flow from the tank to the engine.