Dodge Dakota (R1). Manual — part 494
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.
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
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.
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
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
9 - 164
ENGINE 4.7L
AN
(8) If
bearing-to-journal
clearance
exceeds
the
specification, determin which services bearing set to
use the bearing sizes are as follows:
Bearing
Mark
SIZE
USED WITH
JOURNAL SIZE
.025 US
.025 mm
50.983-50.967 mm
(.001 in.)
(2.0073-2.0066 in.)
Std.
STANDARD
50.992-51.008 mm
(2.0076-2.0082 in.)
.250 US
.250 mm
50.758-50.742 mm
(.010 in.)
(1.9984-1.9978 in.)
(9) Repeat the Plastigage measurement to verify
your bearing selection prior to final assembly.
(10) Once you have selected the proper insert,
install the insert and cap. Tighten the connecting rod
bolts to 27 N·m (20 ft. lbs.) plus a 90° turn.
Slide snug-fitting feeler gauge between the con-
necting rod and crankshaft journal flange (Fig. 55).
Refer to Engine Specifications for the proper clear-
ance. Replace the connecting rod if the side clearance
is not within specification.
Fig. 53 Piston and Connecting Rod—Installation
1 - “F” TOWARD FRONT OF ENGINE
2 - OIL SLINGER SLOT
3 - RING COMPRESSOR
4 - SPECIAL TOOL 8507
Fig. 54 Measuring Bearing Clearance with
Plastigage
1 - PLASTIGAGE SCALE
2 - COMPRESSED PLASTIGAGE
Fig. 55 Checking Connecting Rod Side Clearance—
Typical
AN
ENGINE 4.7L
9 - 165
CONNECTING ROD BEARINGS (Continued)
CORE PLUGS
REMOVAL
(1) Drain the cooling system (Refer to 7 - COOL-
ING - STANDARD PROCEDURE).
(2) Using a blunt tool such as a drift or a screw
driver and a hammer, strike the bottom edge of the
cup plug (Fig. 56)
(3) Using a suitable pair of pliers, grasp the core
plug and remove.
INSTALLATION
NOTE: Thoroughly clean core plug bore, remove all
of the old sealer.
(1) Coat the edges of the engine core plug and the
core plug bore with Mopar Gasket Maker, or equiva-
lent.
NOTE: It is not necessary to wait for the sealant to
cure on the core plugs. The cooling system can be
filled and the vehicle returned to service immedi-
ately.
(2) Using proper plug driver, drive core plug into
the core plug bore. The sharp edge of the core plug
should be at least 0.50 mm (0.020 in.) inside the lead
in chamfer.
(3) Refill the cooling system (Refer to 7 - COOL-
ING - STANDARD PROCEDURE).
CRANKSHAFT
DESCRIPTION
The crankshaft is constructed of nodular cast iron.
The crankshaft is a crosshaped four throw design
with eight counterweights for balancing purposes.
The crankshaft is supported by five select fit main
bearings with the number three serving as the thrust
washer location. The main journals of the crankshaft
are cross drilled to improve rod bearing lubrication.
The number eight counterweight has provisions for
crankshaft position sensor target wheel mounting.
The select fit main bearing markings are located on
the rear side of the target wheel. The crankshaft oil
seals are one piece design. The front oil seal is
retained in the timing chain cover, and the rear seal
is pressed in to a bore formed by the cylinder block
and the bedplate assembly.
REMOVAL
NOTE: To remove the crankshaft from the engine,
the engine must be removed from the vehicle.
(1) Remove the engine. (Refer to 9 - ENGINE -
REMOVAL).
(2) Remove the engine oil pump.(Refer to 9 -
ENGINE/LUBRICATION/OIL PUMP - REMOVAL).
CAUTION: DO NOT pry on the oil pan gasket when
removing the oil pan, The oil pan gasket is mounted
to the cylinder block in three locations and will
remain attached to block when removing oil pan.
Gasket can not be removed with oil pan.
(3) Remove oil pan. (Refer to 9 - ENGINE/LUBRI-
CATION/OIL PAN - REMOVAL).
(4) Remove the oil pump pickup tube and oil pan
gasket /windage tray.
(5) Remove the bedplate mounting bolts. Note the
location of the three stud bolts for installation.
(6) Remove the connecting rods from the crank-
shaft.
CAUTION: The bedplate to cylinder block mating
surface is a critical sealing surface. Do not pry on
or damage this surface in anyway.
NOTE: The bedplate contains the lower main bear-
ing halves. Use care when handling bedplate as not
to drop or damage bearing halves. Installing main
bearing halves in the wrong position will cause
sever damage to the crankshaft.
Fig. 56 Engine Core Plug Removal
1 - CYLINDER BLOCK
2 - REMOVE PLUG WITH PLIERS
3 - STRIKE HERE WITH HAMMER
4 - DRIFT PUNCH
5 - CUP PLUG
9 - 166
ENGINE 4.7L
AN
NOTE: The bedplate has pry points cast into it. Use
these points only. The pry points are on both the
left and right sides, only the left side is shown.
(7) Carefully pry on the pry points (Fig. 57) to
loosen the bedplate then remove the bedplate.
CAUTION: When removing the crankshaft, use care
not to damage bearing surfaces on the crankshaft.
(8) Remove the crankshaft.
(9) Remove the crankshaft target wheel.
INSPECTION
NOTE: Thoroughly inspect the connecting rod bear-
ing bores and main bearing bores for scoring, blue-
ing or severe scratches. Further disassembly may
be required.
If connecting rod bearing bores show damage, the
cylinder heads must be removed to service the piston
and rod assemblies. If the bedplate or the cylinder
block main bearing bores show damage the engine
must be replaced.
(1) If required, remove the main bearing halves
from the cylinder block and bedplate.
(2) Thoroughly clean the bedplate to cylinder block
sealing surfaces and main bearing bores. Remove all
oil and sealant residue.
(3) Inspect the bedplate main bearing bores for
cracks, scoring or severe blueing. If either condition
exists the engine must be replaced.
(4) Inspect the crankshaft thrust washer for scor-
ing, scratches or blueing. If either condition exist
replace the thrust washer.
(5) Inspect the oil pan gasket/windage tray for
splits, tears or cracks in the gasket sealing surfaces.
Replace gasket as necessary.
INSTALLATION
CAUTION: Main bearings are select fit. (Refer to 9 -
ENGINE/ENGINE
BLOCK/CRANKSHAFT
MAIN
BEARINGS - STANDARD PROCEDURE) for proper
bearing selections.
(1) Lubricate upper main bearing halves with
clean engine oil.
CAUTION: When installing crankshaft, use care not
to damage bearing surfaces on the crankshaft.
NOTE: Apply sealant to the target wheel retaining
screws prior to installation.
(2) Install the crankshaft target wheel. Torque the
mounting screws to 22 N·m (21 ft. lbs.).
(3) Position crankshaft in cylinder block.
(4) Install the thrust washers (Fig. 58).
Fig. 57 Bedplate Pry Point Location
1 - CYLINDER BLOCK
2 - BEDPLATE
3 - PRY POINT
Fig. 58 Crankshaft Thrust Washer Installation
1 - CRANKSHAFT THRUST WASHER
AN
ENGINE 4.7L
9 - 167
CRANKSHAFT (Continued)
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