Komatsu 4D98 Series Shop Manual page 108

8. Turbocharger (for 4TNE106T)
(2.4)
Turbine shaft 1
@ Inspect any contact trace, chipping, thermal discoloration or deformation at the turbine
wheel. Check the shaft portion for bend, the journal portion for thermal discoloration or
abnormal wear, and the seal ring groove for surface defect or wear. Replace with a new
one if defective.
@ Measure the turbine shaft journal outside di-
ameter (A) and seal ring groove width (E).
Replace with a new turbine shaft if beyond
the wear limit.
Journal outside diameter (A)
Wear limit : 7.98
mm
Ring groove width
(E)
Wear limit
: 1.29 mm
@ Measure the turbine shaft run-out, and re- V block
place with a new turbine shaft if it exceeds
0.011 mm.
(2.5)
Heat insulating plate 20
Inspect the heat insulating plate for any contact trace, thermal deformation or corrosion.
Replace with a new one if defective.
(2.6) Thrust bushing, oil thrower 2 and thrust bearing 6
Inspect each part for wear, surface defect and discoloration.
Thrust bushing
Replace with a new one if defective even within the wear limit.
Thrust bushing
Measure the distance between grooves (K)
of the thrust bushing, and replace with a new
one if the wear limit is exceeded.
Wear limit
:
4.07
mm
Oil thrower 2
Measure the seal ring groove widths (Gl)
and (G2), and replace with a new one if the
wear limit is exceeded.
Wear limits : Gl:
1.31 mm, G2: 1 -11 mm
Thrust bearing 6
Measure the thrust bearing width (J), and replace with a new one if the wear limit is ex-
ceeded.
Wear limit : 3.98
mm
(2.7) Floating bearing 5
@) Inspect the floating bearing for abnormal wear, discoloration or surface defect.
Replace with a new one if defective.
@ Measure the inside diameter (C) and outside diameter (D).
Replace the bearing if either wear limit is exceeded.
Wear limits:
Outside diameter
(D):
12.31
mm
Inside diameter (C): 8.04
mm
8-12