High temperature is very harmful to the engine, and it is also the main reason that affects the work of the spark plug.
1. The original calorific value of the spark plug is destroyed, and the spark plug porcelain is prone to cracks. High temperature will deform the shell, affect heat conduction, and change its own operating temperature. High temperature will also change the density of porcelain parts, which can easily cause cracks and cause internal discharge failure of the spark plug.
2. The spark plug shell after high temperature will undergo large deformation due to thermal expansion and contraction. This deformation affects the sealing and torque of the spark plug installation thread. Moreover, carbides produced by combustion will enter inside the threads. This carbide will cause the spark plug and cylinder head threads to be sintered together. During the disassembly process, more torque is required. However, if the torque is too large, it is easy for the spark plug to break in the cylinder. Inside the cover.
3. When the engine is running, the temperature of the spark plug itself will increase, and the change in calorific value and the entry of carbides into the thread will directly affect the heat dissipation of the spark plug, which will easily cause the spark plug electrode to sinter and increase the gap, thus causing the engine to misfire and lack of cylinders. . Especially when driving at high speed, due to engine misfire, the unburned mixture will be burned together in the next combustion, and the temperature in the cylinder will rise sharply, further causing knocking. When the engine is at high speed, knocking is very harmful and can cause serious failures such as piston melting and cylinder pullout.
