Sparg Plug Sparg Plug
A spark plug is necessary in gas engines to ignite the air-fuel mixture. A self cleaning temperature of 400 °C should be reached in short time and not go beyond 850°C.
Ignition spark builts ions between a central electrode (figure 2 upper right) and one or more side electrodes (figure 2 lower right). The central electrode is surrounded by an isolator influences heat range by shorter or longer distance to cooling cylinder head. 'Cold' spark plugs are for high performance engines and have a high heat range (low heat range number). A deep reaching isolator means the opposite. The right spark plug has to be chosen for each combustion-chamber configuration. A spark plug reading: 'W8DC' is a Bosch brand plug for low output engines.
The isolator is made from aluminumoxide, elektrodes from nickel-mangan-, chrome- or silveralloys, sometimes platinum.