Pistons and Piston Rings

Pistons





Installation position: arrow on piston crown must point in driving direction.
- Mark cylinder number on piston crown using waterproof felt pen.

CAUTION: DO NOT scratch or scribe on piston crown. The surface has a coating that must not be damaged.

Checking piston diameter





- Measure pistons approximately 10 mm (3/8 inch) from bottom edge at right angle (90°) to piston pin.
Deviation from nominal size: 0.04 mm (0.0016 inch).





Piston and cylinder bore dimensions








Checking piston ring side clearance





Checking piston ring end gap
- Insert ring at right angle from top and slide down into lower cylinder opening until approximately 15 mm from lower edge of cylinder.





Engine codes ACK, AHA