Piston Measurement Procedure
WARNING: This page is about a different variant/trim than selected.
Measure piston width using the following procedure:
- Using an outside micrometer, measure the width of the piston at 30 mm (1.181 in) below the crown, top, (1) at the thrust surfaces of the piston, perpendicular to the piston pin centerline.
- Compare the measurement of the piston to its original cylinder by subtracting the piston width from the cylinder diameter.
- Check your measurements with the Engine Mechanical Specifications .
- If the clearance obtained through measurement is greater than the provided specifications and the cylinder bores are within specification, replace the piston.
Measure the piston pin bore to piston pin clearances using the following procedure:
- Piston pin bores and pins must be free of varnish or scuffing.
- Use an outside micrometer to measure the piston pin in the piston contact areas.
Using an inside micrometer, measure the piston pin bore. Compare your result with the piston pin diameter and piston pin to piston pin bore clearance listed in the Engine Mechanical Specifications .
- If the clearance is excessive, determine which piece is out of specification and replace as necessary.
- You must replace the piston if any of its dimensions are out of specification.
- If the new piston does not meet clearance specifications, the cylinder block may need to be oversized to 0.25 mm (0.010 in). There is only one size of oversized pistons and rings available for service.