How to Tune Up Murray Lawn Mowers

Lift up the seat support housing to expose the top end of the mower. The support housing does not bolt into place. You will locate a small raised lip on the front of the housing so you can easily lift it up.

Locate the black spark plug wire. One end of the wire plugs onto the spark plug and the other end of the wire plugs onto the coil. Remove the wire from the spark plug and the coil by pulling the wire boots off each component by hand.

Remove the spark plug with a spark plug socket and ratchet. Thread the replacement spark plug into the engine head with your fingers and then tighten it with the spark plug socket and ratchet.

Plug the spark plug boots from the replacement spark plug wire onto the spark plug and the coil.

Start the engine and let it run for two or three minutes to warm up the engine oil. Turn the mower off.

Position a drain pan under the motor to catch the oil. Pull the dipstick out of the dipstick tube and then remove the yellow drain cap and allow the oil to drain.

Close the yellow drain plug and then stick a funnel into the dipstick tube. Fill the engine with 10W30 motor oil. Add one quart and then check the oil level with the dipstick. Add additional oil as needed until the level of oil reaches the "Full" mark on the dipstick.

Check the tire pressure for each tire with a tire pressure gauge. Each tire has the appropriate pressure labeled on the sidewall. Add additional air as needed with a tire pressure gauge.