Piston Ring, Engine

PISTON RING SIDE CLEARANCE





^ Measure the side clearance of piston ring and piston ring groove with a feeler gauge.
Standard:
Top ring: 0.045 - 0.080 mm (0.002 - 0.003 inch)
2nd ring: 0.030 - 0.070 mm (0.001 - 0.003 inch)
Oil ring: 0.065 - 0.135 mm (0.003 - 0.005 inch)
Limit:
Top ring: 0.11 mm (0.004 inch)
2nd ring: 0.10 mm (0.004 inch)
^ 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.
^ 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 a feeler gauge.
Standard:
Top ring: 0.23 - 0.33 mm (0.009 - 0.013 inch)
2nd ring: 0.33 - 0.48 mm (0.013 - 0.019 inch)
Oil ring: 0.20 - 0.50 mm (0.008 - 0.020 inch)
Limit:
Top ring: 0.54 mm (0.021 inch)
2nd ring: 0.80 mm (0.031 inch)
Oil ring: 0.95 mm (0.037 inch)
^ 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.