Yanmar 3YM30 Sevice Manual page 138

5. Inspection and servicing of basic engine parts
• Other procedure of measuring crank pin oil clearance
1) Use the press gauge (Plastic gauge) for
measuring the oil clearance of the crank pin.
2) Mount the connecting rod on the crank pin (tighten
to specified torque).
3) Remove the connecting rod and measure the
broken plastic gauge with measuring paper.
(3) Precautions on replacement of crank pin
metal
1) Wash the crank pin metal.
2) Wash the large end cap, mount the crank pin
metal and make sure that it fits tightly on the large
end cap.
3) When assembling the connecting rod, match up
the large end and large end cap number. Coat the
bolts with engine oil and gradually tighten them
alternately to the specified torque.
If a torque wrench is not available, make match
marks on the bolt heads and large end cap before
disassembling (to indicate the proper torque
position) and retighten the bolts to those positions.
4) Make sure there is no sand, metal cuttings or
other foreign matter in the lube oil, and that the
crankshaft is not scratched. Take special care in
cleaning the oil holes.
Plastic gauge
Alignment mark (Punched mark)
123
Matching mark