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Piston, Engine


Pistons





Position: arrow on piston crown must always face in direction of travel.
- Mark cylinder number on piston crown with waterproof felt pen.

Note: Do not use a center-punch or similar, as pistons have a special coating.





Checking piston diameter
- Measure pistons approximately 10 mm from bottom of skirt, at 90° to piston pin axis.
^ Difference between actual and nominal diameter: not more than 0.04 mm.








Ring-to-groove clearance








Checking piston ring gap
- Push ring in squarely to a position approximately 15 mm from bottom end of cylinder.