2006 Johnson SD 30 HP 4 Stroke Outboards Service Manual, PN 5006592, Page 157Get this manual
POWERHEAD PISTON, CYLINDER, AND CRANKSHAFT Wrist Pin and Bores Inspect the wrist pin and the bores in the piston and the connecting rod for wear and damageUse micrometer to check the wrist pin outside diameterIf the measurement exceeds the service limit, replace the wrist pinWrist Pin Outside Diameter 0.6297 to 0.6299 inStandard (15.995 to 16.000 mm) Service Limit 0.6291 in(15.980 mm)
Use dial calipers to measure the connecting rod small bore inside diameterIf the measurement exceeds the service limit, replace the connecting rodConnecting Rod Small Bore Inside Diameter
Standard
0.6300 to 0.6304 in(16.003 to 16.011 mm)
Connecting rod small bore
Wrist pin
Use dial calipers to measure the piston bore inside diameterIf the measurement exceeds the service limit, replace the piston assemblyPiston Bore Inside Diameter 0.6302 to 0.6305 inStandard (16.006 to 16.014 mm) 0.6311 in(16.030 mm) Service Limit