Piston Ring, Engine

PISTON RING SIDE CLEARANCE





^ Measure side clearance of the piston ring and piston ring groove using suitable tool.
Standard:
Top ring: 0.035 - 0.085 mm (0.0014 - 0.0033 inches)
2nd ring: 0.030 - 0.070 mm (0.0012 - 0.0028 inches)
Oil ring: 0.015 - 0.050 mm (0.0006 - 0.0020 inches)
Limit:
Top ring: 0.11 mm (0.0043 inches)
2nd ring: 0.10 mm (0.0039 inches)
^ If out of specification, replace piston and/or piston ring assembly.

PISTON RING END GAP





^ Check if the diameter of the cylinder bore is within specification. Refer to "Piston to Cylinder Bore Clearance".
^ Insert the piston ring into the middle of the cylinder using the piston, and measure gap.
Standard
Top ring: 0.23 - 0.33 mm (0.0091 - 0.0130 inches)
2nd ring: 0.25 - 0.40 mm (0.0098 - 0.0157 inches)
Oil ring: 0.20 - 0.60 mm (0.0079 - 0.0236 inches)
Limit:
Top ring: 0.56 mm (0.0220 inches)
2nd ring: 0.52 mm (0.0205 inches)
Oil ring: 0.96 mm (0.0378 inches)
^ If out of specification, replace piston ring. If the gap still exceeds the limit even with a new ring, re-bore the cylinder and use oversized piston and piston ring.