1. According to Chongqing cylinder head manufacturers with high sales volume: due to improper repairs, the gap between the piston and the cylinder is large, or the gap is too large due to severe cylinder wear. The piston gap is large when the engine is cold, and the abnormal noise of the cylinder is severe. After the temperature rises, the piston expands, which makes the fit clearance of the piston smaller, and the abnormal sound of knocking the cylinder will be reduced or disappeared.
2. Poor lubrication conditions, low oil pressure or low oil viscosity, poor splash lubrication of the cylinder wall, and the formation of a normal lubricating oil film between the piston and the cylinder wall. The piston and the cylinder directly collide and knock the cylinder. According to Chongqing cylinder head manufacturers That being said, this is one of the most common reasons.
3. The lubricating oil passage is blocked and cannot form normal pressure lubrication; the connecting rod bush or the piston pin is too tight, which causes the piston to make a sound when it hits the cylinder wall.
4. Xiaobian made a special consultation with Chongqing Cylinder Head Sales Center, which is currently the hottest in China. The person in charge introduced that when too much carbon deposits in the combustion chamber caused the compression ratio of the diesel engine to increase, the gas pressure and temperature were too high, and the misty diesel injected into the cylinder encountered The high-temperature and high-pressure gas fires and produces so-called knock. According to the maintenance personnel of the Chongqing cylinder head manufacturer, the flame propagated outward at a very high rate during the detonation, and even when the gas was too late to expand, the temperature and pressure rose sharply, forming a pressure wave and advancing at the speed of sound. When this pressure wave hits the cylinder wall, it makes a sharp knocking sound.