Insufficient ignition and combustion may cause carbon deposits or engine shortage. The spark plug needs to dissipate heat. If it is not tightened, the spark plug and the cylinder head will not fit tightly, resulting in poor heat dissipation.
Failure to install the spark plug will result in arc deformation of the spark plug gasket, leading to air leakage during engine operation, reduced power, blocking the heat dissipation passage, and preventing the heat absorbed by the spark plug from the combustion chamber from being transmitted. The accumulation of heat sharply increases the internal temperature of the spark plug and burns the ignition end including the insulator skirt, the center electrode, and the side electrode.
The lighter causes the main electrode of the spark plug to overheat and reduce the life, and the lighter causes pre-ignition and knock, and even the spark plug electrode falls off the cylinder.
Leak, high temperature mixed oil and gas leak out around the spark plug. Fuel consumption increases, power decreases, and acid glue will form between the spark plug and the cylinder head over a long time, which will cause trouble for replacement in the later maintenance.
The spark plug is installed with a torque wrench. The factory technology requires a tightening torque, which is generally 15-30 Nm. For aluminum cylinder heads, the tightening torque is 25-30 Nm. For cast iron cylinder heads, the tightening torque is 30 to 35 Nm. There is no torque wrench, and the new spark plug feels strained when tightened, and then twist it 1 or 2 times. When the old spark plug is tightened, it feels difficult, and then twist it 2 to 4 times.