What is the operating temperature of a spark plug tip?
Whether a spark plug is installed in a lawn mower, boat, truck, or race car, the plug tip temperature must remain between 450° C and 850° C. If the tip temperature is below 450°C, the insulator area surrounding the center electrode will not be hot enough to burn off carbon and combustion chamber deposits. These deposits will accumulate and foul the plug gap, leading to a misfire. When the tip temperature exceeds 850°C, the ceramic around the tip will blister and the electrodes will melt. Preignition and detonation caused by the overheatede tip are likely to cause engine damage. The borderline netween the fouling and operating regions (450°C) is called the spark plug self-cleaning region. This is the temperature at which the accumulated deposits burn off of the center insulator. A function of temperature only, the self-cleaning region has no relationship to spark quality or intensity.
