Piston Pin: Testing and Inspection

Piston And Piston Pin

1. Check the pistons and piston pins for damage, cracks and wear, and the piston ring grooves for wear and damage. Replace if defective.
2. Measure the piston-to-cylinder clearance at each cylinder. If any of the clearances is not within the standard value, replace the piston. Or bore the cylinder to use an oversize piston.
3. Make sure that the piston pin can be inserted into the piston pin hole with a thumb at 20°C (68°F). Replace if defective.
Clearance between piston hole and piston pin:
Standard 0.004 - 0.008 mm (0.0002 - 0.0003 inch)








4. Check the snap ring installation groove (A) on the piston for burr. If necessary, remove burr from the groove so that the piston pin can lightly move.





5. Check the piston pin snap ring for distortion, cracks and wear.