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 in)
2nd ring: 0.030 - 0.070 mm (0.0012 - 0.0028 in)
Oil ring: 0.065 - 0.135 mm (0.0026 - 0.0053 in)
Limit:
Top ring: 0.11 mm (0.0043 in)
2nd ring: 0.10 mm (0.0039 in)
^ If the measured value exceeds the limit, replace piston ring, and measure again. If it still exceeds the limit, replace piston also.

PISTON RING END GAP





^ Make sure that the cylinder bore inner diameter is within the specification. Refer to EM-127, "Cylinder Bore Inner Diameter. Specifications
^ Lubricate with new engine oil to piston and piston ring, and then insert piston ring until middle of cylinder with piston, and measure the piston ring end gap with feeler gauge.
Standard:
Top ring: 0.23 - 0.33 mm (0.0091 - 0.0130 in)
2nd ring: 0.33 - 0.48 mm (0.0130 - 0.0189 in)
Oil ring: 0.20 - 0.50 mm (0.0079 - 0.0197 in)
Limit:
Top ring: 0.56 mm (0.0220 in)
2nd ring: 0.68 mm (0.0268 in)
Oil ring: 0.85 mm (0.0335 in)
^ If the measured value exceeds the limit, replace piston ring, and measure again. If it still exceeds the limit, re-bore cylinder and use oversize piston and piston rings.