Piston Ring, Engine

PISTON RING SIDE CLEARANCE





^ Measure side clearance of piston ring and piston ring groove with feeler gauge.
Standard:
Top ring: 0.045 - 0.080 mm (0.0018 - 0.0031 inch)
2nd ring: 0.030 - 0.070 mm (0.0012 - 0.0028 inch)
Oil ring: 0.065 - 0.135 mm (0.0026 - 0.0053 inch)
Limit:
Top ring: 0.11 mm (0.0043 inch)
2nd ring: 0.10 mm (0.0039 inch)
^ If out of specification, replace piston and/or piston ring assembly.

PISTON RING END GAP





^ Check if inner diameter of cylinder bore is within specification. Refer to "Piston to Cylinder Bore Clearance".
^ Insert piston ring until middle of cylinder with piston, and measure gap.
Standard:
Top ring: 0.22 - 0.32 mm (0.0087 - 0.0126 inch)
2nd ring: 0.22 - 0.32 mm (0.0087 - 0.0126 inch)
Oil ring: 0.20 - 0.60 mm (0.0079 - 0.0236 inch)
Limit:
Top ring: 0.56 mm (0.0220 inch)
2nd ring: 0.52 mm (0.0205 inch)
Oil ring: 0.96 mm (0.0378 inch)
^ If out of specification, replace piston ring. If gap still exceeds the limit even with a new ring, re-bore cylinder and use oversized piston and piston ring.