Changing Spark Plugs
Select the Right Tool
Take Your Time and Be Careful
Basic Maintenance Everyone Should Know
Changing spark plugs on a car has become something most people don't think about anymore. Today's cars don't require new plugs until they reach 100,000 or more miles. However, if you drive an older car or a "base model" car, this is a skill that you might want to consider learning. This technique won't work for all cars but for most simple engines it should.
Begin by choosing the right plug wrench or socket. Most plug sockets have a hex head on one end so you can get a wrench on the socket when the plug is located in a difficult to reach place. Also, the inside of a plug socket has a rubber boot that protects the spark plugs insulator and helps grip the plug, allowing you to pull the plug out with the socket. Using the right tool (a socket made for removing spark plugs) will save you a lot of headache and skinned knuckles.
Once you have decided which socket truly fits your cars spark plugs, remove a plug wire and slide the socket down over the spark plugs insulator. Change you plugs one at a tim. Never remove more than one spark plug wire at any given time. Once the socket is seated over the plug, go ahead an snap in your wrench to break it free (counterclockwise). Once the plug moves, unthread it by hand.
To install a new plug, press the new spark plug into the socket and allow the rubber book inside the socket to grip the plugs insulator. Set the plug gently into its hole and begin threading it down (clockwise rotations). If the threads have any trouble starting, adjust the angle of the plug and try again. You do NOT want to force the plug - you can strip out the threaded hole and then you'll have a real mess on your hands. Once the plug is threaded all the way down, seat the new washer by attaching your wrench and turning it clockwise about 1/4-turn. It should be pretty snug at this point.