Liner (Cylinder Liner)

A cylinder liner is a hardened metal sleeve fitted inside the engine block.

It provides a smooth surface for the piston to move up and down.

It reduces wear on the engine block, helps transfer heat, and can be replaced when worn.

Piston + Ring

The piston moves inside the cylinder liner to compress the air-fuel mixture and transfer combustion force to the crankshaft.

Piston rings are fitted into grooves on the piston.

They seal the combustion chamber, control engine oil on the cylinder wall, and transfer heat from the piston to the liner.