Paper: Giving Our Lives a Spark,the Wonders of the Spark Plug

The ceramic insert also helps burn off deposits. Ceramic is not a very good heat conductor so it can get very hot during use. That heat does serve a purpose though, it helps to burn off deposits from the electrode. Spark plugs are used for gasoline engines, such as in cars, lawn mowers, snowmobiles, and snow blowers. There is a spark plug in each cylinder. The electric system repeatedly sends electricity to each spark plug in a certain sequence. When the electricity gets to the spark plug the electricity jumps the gap and creates a spark. The spark then ignites the fuel/air mixture in the cylinder which makes an explosion. The explosion pushes down the piston which makes the engine go. Some cars may need a hot plug and some may need a cold plug. On a hot plug the ceramic insert has a smaller contact area with the metal part of the spark plug. Therefore a hot plug will run hotter and burn away more deposits. These are usually used in an engine with a low combustion chamber temperature. On the other hand a cold plug has more contact area so that it will run cooler and in turn will burn off less deposits. Most high performance car engines give off more heat so they would need a cold plug so that it does not get too hot. The goal is to keep either a hot or cold plug at the same temperature if in the right engine. If you run a cold plug in a cold engine it will build up more deposits and not work. If you put a hot plug in a hot engine it will get too hot and burn up. In the years gone by spark plugs have not changed a whole lot. A few different changes could be some changes in material for the ceramic insert or different kinds of metals for the electrode. Another recent change has been the length of the core nose. The advantage of a long core nose is that it will run hotter at low engine speeds but be cooled off by the gas/air mixture. The spark plug over all is an essential part for running a gasoline engine....