What is the clearance between the piston and cylinder wall?

[CameronFitz]

After the piston rings are installed into the cylinder liner, the end gap is generally around 0.2mm (the end gap may vary for different engines). The cylinder liner serves the following purposes: 1. Working space: Together with the cylinder head and piston, it forms the working space of the cylinder. 2. Reciprocating motion: In trunk piston diesel engines, the cylinder liner bears the side thrust from the piston and serves as the guide for the piston's reciprocating motion. 3. Temperature: It transfers heat from the piston assembly and itself to the cooling water to maintain proper operating temperature. 4. Gas exchange: In two-stroke diesel engines, the cylinder liner is equipped with ports that are opened and closed by the piston to achieve gas exchange.