Changing Spark Plugs

Select the Right Tool

Not all plugs are the same size.  Shown here are two different plug sockets.
Not all plugs are the same size. Shown here are two different plug sockets.
A plug socket usually has a rubber liner that grips the insulator on the spark plug, preventing damage.
A plug socket usually has a rubber liner that grips the insulator on the spark plug, preventing damage.

Take Your Time and Be Careful

Do as much as you can with your fingers to avoid stripping out threads or breaking spark plug insulators.
Do as much as you can with your fingers to avoid stripping out threads or breaking spark plug insulators.
Only use a wrench when breaking a plug free initially or to make the last 1/4 turn to seat the plug seal.
Only use a wrench when breaking a plug free initially or to make the last 1/4 turn to seat the plug seal.

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.

Is This a Healthy Spark Plug?

A properly running engines spark plug should have a brown or reddish colored electrode.  If the electrode is black, the car is running too rich.  If its white, its running too lean.
A properly running engines spark plug should have a brown or reddish colored electrode. If the electrode is black, the car is running too rich. If its white, its running too lean.

More by this Author


Comments 1 comment

Ved 6 years ago

Way too lean IMO.

    Sign in or sign up and post using a HubPages Network account.

    0 of 8192 characters used
    Post Comment

    No HTML is allowed in comments, but URLs will be hyperlinked. Comments are not for promoting your articles or other sites.


    Click to Rate This Article
    working