Use a vernier caliper at several points around the piston.
Piston ring/groove width
Standard | Service Limit | |
Top | 0.84-0.86 mm | 0.94 mm |
Second | 0.82-0.84 mm | 0.92 mm |
★ If the width of any of the two grooves is wider than the service limit at any point, replace the piston.