4 - 30ENGCYLINDER AND PISTON3rd step: Find the piston-to-cylinder clearance with thefollowing formula. If out of specification, rebore or replace thecylinder, and replace the piston and pistonrings as a set.*****************************************************Piston-to-cylinder clearance =Cylinder bore “C” –Piston skirt diameter “P”Piston-to-cylinder clearance:0.040 ~ 0.065 mm(0.0016 ~ 0.0026 in): 0.150 mm (0.0059 in)CHECKING THE PISTON RINGS1.Measure: Piston ring side clearanceUse a feeler gauge.Out of specification → Replace the pistonand rings as a set.NOTE:Clean carbon from the piston ring grooves andrings before measuring the side clearance.2.Position: Piston ring(in cylinder)NOTE:Insert a ring into the cylinder and push itapproximately 40 mm (1.6 in) into the cylinder.Push the ring with the piston crown so that thering will be at a right angle to the cylinder bore.a 40 mm (1.6 in)Side clearanceStandard LimitTopring0.03 ~ 0.08 mm(0.0012 ~ 0.0031 in)0.13 mm(0.0051 in)2ndring0.03 ~ 0.07 mm(0.0012 ~ 0.0028 in)0.13 mm(0.0051 in)
