Dodge Dakota Sport 2001 Service Manual page 1193

9 - 164 ENGINE 4.7L
CONNECTING ROD BEARINGS
STANDARD PROCEDURE—CONNECTING ROD
BEARING FITTING
Inspect the connecting rod bearings for scoring and
bent alignment tabs (Fig. 50) (Fig. 51). Check the
bearings for normal wear patterns, scoring, grooving,
fatigue and pitting (Fig. 52). Replace any bearing
that shows abnormal wear.
Inspect the connecting rod journals for signs of
scoring, nicks and burrs.
Fig. 50 Connecting Rod Bearing Inspection
1 - UPPER BEARING HALF
2 - MATING EDGES
3 - GROOVES CAUSED BY ROD BOLTS SCRATCHING
JOURNAL DURING INSTALLATION
4 - WEAR PATTERN — ALWAYS GREATER ON UPPER
BEARING
5 - LOWER BEARING HALF
Misaligned or bent connecting rods can cause
abnormal wear on pistons, piston rings, cylinder
walls, connecting rod bearings and crankshaft con-
necting rod journals. If wear patterns or damage to
any of these components indicate the probability of a
misaligned connecting rod, inspect it for correct rod
alignment. Replace misaligned, bent or twisted con-
necting rods.
(1) Wipe the oil from the connecting rod journal.
(2) Lubricate the upper bearing insert and install
in connecting rod.
(3) Use piston ring compressor and Guide Pins
Special Tool 8507 (Fig. 53) to install the rod and pis-
ton assemblies. The oil slinger slots in the rods must
Fig. 51 Locking Tab Inspection
1 - ABNORMAL CONTACT AREA CAUSED BY LOCKING TABS
NOT FULLY SEATED OR BEING BENT
Fig. 52 Scoring Caused by Insufficient Lubrication
or Damaged Crankshaft Journal
face front of the engine. The "F"'s near the piston
wrist pin bore should point to the front of the engine.
(4) Install the lower bearing insert in the bearing
cap. The lower insert must be dry. Place strip of Plas-
tigage across full width of the lower insert at the cen-
ter of bearing cap. Plastigage must not crumble in
use. If brittle, obtain fresh stock.
(5) Install bearing cap and connecting rod on the
journal and tighten bolts to 27 N·m (20 ft. lbs.) plus a
90° turn. DO NOT rotate crankshaft. Plastigage will
smear, resulting in inaccurate indication.
(6) Remove the bearing cap and determine amount
of bearing-to-journal clearance by measuring the
width of compressed Plastigage (Fig. 54). Refer to
Engine Specifications for the proper clearance. Plas-
tigage should indicate the same clearance
across the entire width of the insert. If the
clearance varies, it may be caused by either a
tapered journal, bent connecting rod or foreign
material trapped between the insert and cap or
rod.
(7) If the correct clearance is indicated, replace-
ment of the bearing inserts is not necessary. Remove
the Plastigage from crankshaft journal and bearing
insert. Proceed with installation.
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