Komatsu 4D98 Series Shop Manual page 60

4. Engine Body
(4)
Servicing points
Point 1
Disassemble:
l
Remove the crankshaft pulley using a gear puller after removing the mounting bolt. When
removing the pulley with the gear puller, use a pad and carefully operate so as not to dam-
age the thread. Set the gear puller securely to prevent the pulley from being damaged.
Reassemble:
l
When installing the crankshaft pulley, apply lube oil to the bolt and carefully assemble so as
not to damage the oil seal.
T=107.9-127.5 Nm (11-13 kgf-m)
Point 2
Reassemble:
l
When installing the gear case cover, do not forget to install the two reinforcing bolts at the
center.
l
Measure the backlash of each gear.
I-
(mm)
Standard Limit
Crankshaft gear,
Camshaft gear,
0.08-0.14
0.16
Fuel injection pump gear,
Idle gear, PTO gear,
Lubricating oil pump gear
0.09-0.15 0.17
Fuel injection pump
l
Apply sealant and install the gear case cover by correctly positioning the two dowel pins.
Point 3
Disassemble:
l
Remove the fuel injection pump drive gear mounting nut, remove the gear using the gear
puller, and remove the fuel injection pump. Do not forget to remove the stay on the rear side.
When extracting the gear using the gear puller, use a pad at the shaft and carefully operate
so as not to damage the thread.
Reassemble:
l
Drive gear nut T = 83.4-93.2Nm (8.5-9.5 kgf-m)
Point 4
Reassemble:
l
Assemble crankshaft gear A, fuel injection pump drive gear B and camshaft gear C at the
same time by aligning with idle gear A, B and C marks.
l
Install the idle gear shaft with the oil hole facing upward.
Point 5
Reassemble:
l
Install the PTO drive gear with its inner spline side facing the flywheel.
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