Komatsu 4D98 Series Shop Manual page 76

4. Engine Body
(5.5) Connecting rod
(mm)
Standard Limit
4TN E94=98
Piston pin I.D.
bushing 30.025-30.038
30.068
Pin O.D.
29.987-30.000 29.959
Clearance 0.025-0.051
0.109
4TNE106 (T)
Piston pin I.D.
bushing 37.025-37.038 37.068
Pin O.D. 36.989-37.000 36.961
Clearance
0.025-0.049 0.107
If the bushing is to be replaced because
the oil clearance exceeds the limit, use
spare part.
11
Rod big end measurement
Measure the crankpin and bushing ac-
cording to (5.2)@ described above.
0
4-28
Appearance inspection
Inspect the portion near the boundary
of the chamfered portion and I-beam
section of the big and small ends of the
connecting rod as well as the portion
near the oil hole of the bushing at the
small end for cracks, deformation, and
discoloration.
Twist and parallelism measurement
Use a connecting rod aligner and mea-
sure the twist and bend.
@ Rod small end measurement
Measure the pin outside diameter ac-
cording to (5.4)@ described above.
Twist and Darallelism measurement
Connecting rod -
ahgner
I
Twist measuiement using
a connecting rod aligner
Connecting rod small end
1