Piston Ring: Service and Repair
PISTON RING1) Make sure the piston ring is not broken or damaged.
2) Using a cylindrical guide, insert the piston ring and oil ring into the cylinder liner so that they are perpendicular to the cylinder wall, and check the piston ring gap using a thickness gauge. If it is not within the standard, replace the piston ring or oil ring.
NOTE:
Use piston ring with same size as piston when replacing piston ring.
Piston ring gap:
Standard
Top ring
0.20 - 0.30 mm (0.0079 - 0.0118 in)
Second ring
0.30 - 0.45 mm (0.0118 - 0.0177 in)
Oil ring rail
0.20 - 0.50 mm (0.0079 - 0.0197 in)
3) Fit the piston ring straight into the piston ring groove, then check the clearance between piston ring and piston ring groove with a thickness gauge. If it is not within the standard, replace the piston ring or oil ring.
NOTE:
^ Before measuring the clearance, clean the piston ring groove and piston ring.
^ Use piston ring with same size as piston when replacing piston ring.
Clearance between piston ring and piston ring groove:
Standard
Top ring
0.040 - 0.080 mm (0.0016 - 0.0031 in)
Second ring
0.030 - 0.070 mm (0.0012 - 0.0028 in)
