Dodge dakota 2002 Service Manual page 1382

DR
CRANKSHAFT MAIN
BEARINGS
STANDARD PROCEDURE—CRANKSHAFT MAIN
BEARING - FITTING
MAIN BEARING JOURNAL DIAMETER
(CRANKSHAFT REMOVED)
Crankshaft removed from the cylinder block.
Clean the oil off the main bearing journal.
Determine the maximum diameter of the journal
with a micrometer. Measure at two locations 90°
apart at each end of the journal.
The maximum allowable taper is 0.008mm (0.0004
inch.) and maximum out of round is 0.005mm (0.002
inch). Compare the measured diameter with the jour-
nal diameter specification (Main Bearing Fitting
Chart). Select inserts required to obtain the specified
bearing-to-journal clearance.
CRANKSHAFT MAIN BEARING SELECTION
The main bearings are "select fit" to achieve proper
oil clearances. For main bearing selection, the crank-
shaft position sensor target wheel has grade identifi-
cation marks stamped into it (Fig. 62). These marks
are read from left to right, corresponding with jour-
nal number 1, 2, 3, 4 and 5. The crankshaft position
sensor target wheel is mounted to the number 8
counter weight on the crankshaft.
Fig. 62 Main Bearing Markings on Target Wheel
1 - REARMOST CRANKSHAFT COUNTER WEIGHT
2 - TARGET WHEEL
3 - MAIN BEARING SELECT FIT MARKINGS
NOTE: Service main bearings are coded. These
codes identify what size (grade) the bearing is.
MAIN BEARING SELECTION CHART—4.7L
GRADE SIZE mm
(in.)
MARKING
A 0.008 mm
U/S
(0.0004 in.)
U/S
B NOMINAL
C 0.008 mm
O/S
(0.0004 in.)
O/S
INSPECTION
Wipe the inserts clean and inspect for abnormal
wear patterns and for metal or other foreign material
imbedded in the lining. Normal main bearing insert
wear patterns are illustrated (Fig. 63).
Fig. 63 Main Bearing Wear Patterns
1 - UPPER INSERT
2 - NO WEAR IN THIS AREA
3 - LOW AREA IN BEARING LINING
4 - LOWER INSERT
NOTE: If any of the crankshaft journals are scored,
the crankshaft must be repaired or replaced.
Inspect the back of the inserts for fractures, scrap-
ings or irregular wear patterns.
Inspect the upper insert locking tabs for damage.
Replace all damaged or worn bearing inserts.
ENGINE - 4.7L 9 - 133
FOR USE WITH
JOURNAL SIZE
63.488–63.496 mm
(2.4996–2.4999 in.)
63.496–63.504 mm
(2.4999–2.5002 in.)
63.504–63.512 mm
(2.5002–2.5005 in.)