Poor cooling will cause the car cylinder liner, the piston temperature is too high, and poor lubrication; poor cooling will cause the piston and the car cylinder liner to overheat and expand and deform, losing the original normal clearance and pulling the cylinder. The reasons for the poor cooling are: the cooling water pump discharge pressure Insufficient, insufficient or interrupted water supply; the cooling water cavity is rusted or dirty; air contains air bubbles, which are accumulated in the cooling cavity and are not released, causing air resistance; the water quality is too dirty and the water temperature is too high.
The piston ring is not working properly: the gap of the opening is too small, the piston ring is broken; the gap of the earth and the ground is too small, the piston ring is stuck; too much carbon deposit makes the piston ring stuck in the ring groove to lose elasticity, causing fracture or gas leakage; opening The gap is too large or the wear is serious, and air leakage occurs. The leakage of gas damages the lubricating oil film and makes the surface temperature too high. After the piston ring breaks, the debris is easy to fall between the piston and cylinder, causing the cylinder to pull and bite the cylinder.
Burning inferior fuel: incomplete combustion brings more combustion residues; serious post-combustion causes the exhaust temperature to rise, and technical measures are not taken in a timely manner; the cylinder lubrication base value is not suitable. In addition, some diesel engines are operated for long periods of overload. Increased thermal load, overheating expansion or poor alignment of moving parts, pulling the cylinder.