Detroit Diesel 4000 Series, Service Manual, Page: 417 / 2706

SERIES 4000 12/16V SERVICE MANUAL
7. During each assessment of groove condition, the running surface in the area subject to
least load (with groove mostly new) should be used for comparison.
8. The condition of the sputtered bearings is assessed in five groups:
3
Continued use.
3
Wear.
3
Borderline wear and levelling.
3
Wear layer fatigue fractures.
3
Borderline fatigue fractures and empty grooves.
Damage to Bearings
Damage to bearings occurs mainly through foreign body scoring, impressions and bedding,
cavitation and corrosion, pitting, fatigue and installation faults. Bearings showing such damage
must be replaced.
Listed in Table 24 are types of main bearing damage.
Type of Damage Inspection Procedure
1. Continued Use Refer to section Continued Use
2. Wear Refer to section Wear
3. Borderline Wear and Leveling Refer to section Borderline Wear and Leveling
4. Wear Layer Fatigue Fractures Refer to section Wear Layer Fatigue Fractures
5. Borderline Case: Wear Layer Fatigue Frac-
ture and Empty Grooves Refer to section Borderline Case: Wear Layer
Fatigue Fracture and Empty Grooves
Table 24 Crankshaft Bearing Damage
Continued Use
Condition
The groove geometry corresponds to new condition. The wear layer is fully retained within
the grooves. Dark spots are primarily embedded particles of oil carbon. See Figure 196 and
see Figure 197.
All information subject to change without notice.
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