Abnormal Wear: Longitudinal scratches appear on the piston skirt, usually caused by poor lubrication or impurities.
Ring Groove Carbon Deposits: Incomplete combustion can cause piston ring sticking, resulting in reduced power.
Top Erosion: Prolonged high-temperature operation may cause pitting on the piston top surface.
Loose Pin Holes: Manifests as a knocking sound; timely replacement is necessary to prevent cylinder scoring.
