Aluminum oxide
Ceramic
Ceramic
The part that cracks on a spark plug is the insulating material that shields the metal part of the plug that conducts the electrical spark, potentially allowing it to escape or leak and possibly ignite any flammable substances or materials as it grounds itself.
Porcelain
The compatible spark plug is numbered 791-610311B. The spark plug body may have 794-00050 on it.
Get a spark plug socket and wrench that fits the plug body and remove it by turning counter-clockwise.
If you mean that the wire came out of the boot, then pull the boot off of the spark plug and use a spark plug socket to remove the spark plug.
On a carburetors motor pull the coil wire from the distributor cap (the plug wire in the center of the distributor). This is usually found between the air cleaner and the firewall. Remove the desired spark plug from the engine block, plug it into the coil wire and touch the spark plug body (the metal portion) to the engine block while cranking the engine. You will see spark if the plug is good.
Spark plug wire not connected to spark plug? Spark plug wire connected to Wrong spark plug? Vacuum line disconnected? Bad spark plug or wire?
An electrical plug contains both conducting and insulating elements.
To change the spark plugs in a Chevy Celebrity: 1. Give the spark plug boot a twist to free it up from the spark plug, then pull on the boot to remove the spark plug wire from the spark plug. 2. Use a 5/8" spark plug socket with an extension and ratchet or breaker bar to loosen then remove the spark plug. 3. Set the gap on the new plug to .045" then screw it back into the spark plug hole in the head. Tighten the spark plug and replace the spark plug wire. I change the spark plugs one at a time to keep from getting the spark plug wires on the wrong spark plug.
Spark plugs use several materials, including steel, copper, platinum, porcelain, and a mineral called kyanite.
Champion Spark Plug QC12YC