Komatsu 4D98 Series - Crankshaft, Piston, and Bearing Standards

12. Service Standard9
(2.2) Idle gear shaft and bushing
Inspection item
Shaft outside diameter mm
Bushing inside diameter mm
Clearance mm
(2.3) Backlash of each gear
Inspection item
Crank gear, cam gear, idle gear, fuel injection pump gear
and PTO gear
Lubricating oil pump gear
Standard
45.950 - 49.975
46.000 - 46.025
0.025 - 0.075
Standard
0.08 - 0.14
0.09 - 0.15
Limit
Reference
page
45.900
46.075
4-15
0.175
Limit
Reference
page
0.16
4-12
0.17
(3) Cylinder block
(3.1) Cylinder block
Inspection item
Standard
Limit
Reference
page
Cylinder inside diameter mm 4TNE94 94.000 - 94.030 94.130
4TNE98 98.000 - 98.030 98.130
4TNE106 (T) 106.000 - 106.030
106.130 4-21
Cylinder bore Roundness
Inclination
0.01 or less 0.03
(3.2) Crankshaft
Inspection item
Bending (l/2 the dial gage reading)
mm
Standard Limit
0.02
Reference
page
Crank pin
mm
Crank journal
mm
4TNE94*98
4TNE106 (T)
4TNEQ4*98
4TNElO6 (T)
(3.3) Thrust bearing
Inspection item Standard Limit
Reference
page
Crankshaft side gap mm 4TNE94.98 0.11 - 0.21
4-19
4TNE106 IT) 0.13 - 0.23
12-4