What Are the Causes of Piston Wear?

[OSarah]

Piston wear can be severe due to several reasons: the piston ring gap being too small, causing it to seize in the cylinder after thermal expansion during operation; the engine operating under high temperature and heavy load conditions for extended periods, leading to severe piston impacts or insufficient coolant, resulting in engine overheating and reduced mechanical strength of the piston; or manufacturing defects in the piston. Severe piston pin noise or piston slap, if not addressed promptly, may also cause abnormal piston damage. The main causes of severe piston wear are as follows: 1. Piston skirt wear: The wear on the piston skirt is relatively minor, typically forming oval-shaped wear and scuffing due to side pressure and inertial forces. When the clearance between the piston skirt and the cylinder wall is too large, the engine is prone to piston slap and severe oil consumption. 2. Piston pin and pin bore wear: The wear between the piston pin and its bore is usually caused by gas pressure and inertial forces, resulting in oval-shaped wear. The most significant wear occurs in the vertical direction of the bore, leading to loose fitting between the piston and pin and causing abnormal noise.