Piston and Piston Pin Clearance

PISTON AND PISTON PIN CLEARANCE
Piston Pin Bore Diameter





^ Measure the piston pin bore diameter with an inside micrometer.
^ Service parts apply only to grade 0.
Piston pin bore diameter
Grade No. 0: 19.993 - 19.999 mm (0.7871 - 0.7874 inch)
Grade No.1: 19.999 - 20.005 mm (0.7874 - 0.7876 inch)

Outer Diameter of Piston Pin





^ Measure outer diameter of piston pin with a micrometer.
Piston pin outer diameter
Grade No. 0: 19.989 - 19.995 mm (0.7870 - 0.7872 inch)
Grade No.1: 19.995 - 20.001 mm (0.7872 - 0.7874 inch)

Piston to Piston Pin Clearance





(Piston to piston pin clearance) = (Piston pin bore diameter) - (Outer diameter of piston pin)
Standard: 0.002 - 0.006 mm (0.0001 - 0.0002 inch)
If clearance exceeds specification, replace either or both of piston/piston pin assembly and connecting rod assembly with reference to specification of each parts.
^ Refer to piston selection table to replace piston/piston pin assembly. Refer to HOW TO SELECT A PISTON.
^ Refer to connecting rod bearing selection table to replace connecting rod. Refer to HOW TO SELECT A CONNECTING ROD BEARING.





NOTE:
^ The connecting rod small end grade and piston pin hole (piston pin) grade are provided only for the parts installed at the plant. For service parts, no grades can be selected. Only 0 grade is available.
^ Refer to CONNECTING ROD BUSHING OIL CLEARANCE (SMALL END) for the values for each grade at the plant.
^ Regarding marks on piston head, refer to HOW TO SELECT A PISTON.