Crank Pin Metal - Yanmar 3YM30 Service Manual

(2) Checking the side clearance of a connecting
rod
Fit the respective crank pins to the connecting rod and
check to make sure that the side clearance in the
crankshaft direction is correct.
Connecting rod
side clearance

5.4.2 Crank pin metal

(1) Checking crank pin metal
Check for flaking, melting or seizure on the contact surface of the crank pin metal.
(2) Measuring crank pin oil clearance
Measure the crankpin outside diameter and the crank
pin metal inside diameter. Calculate the oil clearance
from the measured values.
(Refer to 5.5.1(3) for measuring the crank pin outside
diameter.)
Replace the crank pin metal if the oil clearance
becomes about the limit dimension of the below table.
Correct by grinding if unevenly wear, roundness
exceeding the limit or insufficient outside diameter is
found. Also use an undersized metal if necessary.
[NOTICE]
When measuring the inside diameter of the rod big
end, install the crank pin metal in the rod big end not
to mistake the top and bottom of the metals and
tighten the rod bolts by the standard torque.
Rod bolt tightening torque
3YM30
Item
Crankpin O.D. 41.952-41.962
Metal I.D. 41.982-42.010
Metal thickness 1.503-1.509
Clearance 0.020-0.058
3YM20/2YM15
Item
Crankpin O.D. 37.952-37.962
Metal I.D. 37.982-38.010
Metal thickness 1.503-1.509
Clearance 0.020-0.058
Standard Limit
0.20-0.40 0.55
N•m (kgf•m)
22.6-27.5
(2.3-2.8)
Standard Limit
41.902
0.120
Standard Limit
37.902
0.120
5. Inspection and servicing of basic engine parts
(Connecting rod side gap)
(Rod bushing I.D. measurement)
mm
-
-
mm
-
-
122R1
Crankshaft
Thickness gage
Cylinder gage