What are the causes of piston knocking noise in the cylinder?
1 Answers
Piston knocking noise in the cylinder is caused by: 1. Excessive wear between the piston and cylinder leading to excessive clearance; 2. Poor lubrication of the cylinder wall; 3. Incorrect piston installation direction or piston deformation; 4. Bent or twisted connecting rod; 5. Severe carbon buildup in the combustion chamber; 6. Excessive fuel injection advance angle; 7. Blocked lubrication oil passages; 8. Overly thin cylinder gasket or excessive wear on the cylinder block top surface, resulting in increased compression ratio in diesel engines; 9. Excessively fast combustion speed of the combustible mixture, causing excessively high pressure in the cylinder. The effects of piston knocking are: 1. Loud noise; 2. Piston cracking and cylinder head deformation; 3. Increased engine compression ratio, making combustion prone to knocking; 4. Damage to the cylinder head; 5. Bent or deformed connecting rod.