What Does Cylinder Scoring Mean?

[OAllie]

Cylinder scoring is one of the common failures in automobile engines. It refers to deep grooves being formed on the inner wall of the cylinder, causing the piston and piston rings to lose their sealing ability when rubbing against the cylinder wall. This results in reduced cylinder compression pressure and loss of power. In severe cases, adhesive wear may occur, leading to difficulties in starting the engine or unexpected stalling. It is a major incident for the engine. The root cause of cylinder scoring is the inability to form an oil film between the cylinder wall and the piston rings or piston, resulting in poor lubrication or even dry friction. Specific reasons for this condition include: 1. Piston ring clearance being too small; 2. Piston pin displacement; 3. Piston-to-cylinder clearance being too small or too large; 4. Severe carbon buildup on piston rings; 5. Severe piston misalignment.