What Causes Cylinder Scoring?

[GabrielleRose]

Cylinder scoring can be attributed to the following reasons: 1. Poor cylinder lubrication. Insufficient or interrupted supply of cylinder lubricating oil leads to direct metal-to-metal contact, resulting in cylinder scoring. 2. Inadequate running-in. To achieve effective running-in within the shortest possible time, both the duration and load distribution must be carefully considered. Prolonged running-in under excessively low loads may still fail to complete the process, while rushing into high-load operation can cause cylinder scoring. 3. Insufficient cooling. Poor cooling leads to excessive temperatures in the cylinder and piston, causing lubrication issues. It also causes the piston and cylinder liner to overheat, expand excessively, and deform, losing their normal clearance and resulting in cylinder scoring. 4. Abnormal piston ring operation. Gas leakage damages the lubricating oil film, raising surface temperatures. Broken piston ring fragments can easily fall between the piston and cylinder, leading to cylinder scoring or seizure.