(19) Install oil fill housing onto cylinder head.
(20) Refill the cooling system.
(21) Raise the vehicle.
(22) Install the exhaust pipe onto the right
exhaust manifold.
(23) Lower the vehicle.
(24) Reconnect battery negitive cable.
(25) Start the engine and check for leaks.
CAMSHAFT(S)
DESCRIPTION
The camshafts consist of powdered metal steel
lobes which are sinter-bonded to a steel tube. Four
bearing journals are machined into the camshaft.
Camshaft end play is controlled by two thrust walls
that border the nose piece journal. Engine oil enters
the hollow camshafts at the third journal and lubri-
cates every intake lobe rocker through a drilled pas-
sage in the intake lobe.
REMOVAL
CAUTION: When the timing chain is removed and
the cylinder heads are still installed, DO NOT force-
fully rotate the camshafts or crankshaft indepen-
dently of each other. Severe valve and/or piston
damage can occur.
CAUTION: When removing the cam sprocket, timing
chains or camshaft, Failure to use special tool 8379
will result in hydraulic tensioner ratchet over exten-
sion, Requiring timing chain cover removal to re-set
the tensioner ratchet.
(1) Remove the cylinder head cover. Refer to CYL-
INDER HEAD COVER in this section.
(2) Set engine to TDC cylinder #1, camshaft
sprocket V6 marks at the 12 o'clock position.
(3) Mark one link on the secondary timing chain
on both sides of the V6 mark on the camshaft
sprocket to aid in installation.
CAUTION: Do not hold or pry on the camshaft tar-
get wheel for any reason, Severe damage will occur
to the target wheel. A damaged target wheel could
cause a vehicle no start condition.
(4) Loosen butDO NOTremove the camshaft
sprocket retaining bolt. Leave bolt snug against
sprocket.
NOTE: The timing chain tensioners must be
secured prior to removing the camshaft sprockets.
Failure to secure tensioners will allow the tension-ers to extend, requiring timing chain cover removal
in order to reset tensioners.
CAUTION: Do not force wedge past the narrowest
point between the chain strands. Damage to the
tensioners may occur.
(5) Position Special Tool 8379 timing chain wedge
between the timing chain strands. Tap the tool to
securely wedge the timing chain against the ten-
sioner arm and guide.
(6) Remove the camshaft position sensor.
(7) Hold the camshaft with Special Tool 8428 Cam-
shaft Wrench, while removing the camshaft sprocket
bolt and sprocket.
(8) Starting at the outside working inward, loosen
the camshaft bearing cap retaining bolts 1/2 turn at
a time. Repeat until all load is off the bearing caps.
CAUTION: DO NOT STAMP OR STRIKE THE CAM-
SHAFT BEARING CAPS. SEVERE DAMAGE WILL
OCCUR TO THE BEARING CAPS.
NOTE: When the camshaft is removed the rocker
arms may slide downward, mark the rocker arms
before removing camshaft.
(9) Remove the camshaft bearing caps and the
camshaft.
INSTALLATION
(1) Lubricate camshaft journals with clean engine
oil.
NOTE: Position the right side camshaft so that the
camshaft sprocket dowel is near the 10 o'clock
position, This will place the camshaft at the neutral
position easing the installation of the camshaft
bearing caps.
(2) Position the camshaft into the cylinder head.
(3) Install the camshaft bearing caps, hand tighten
the retaining bolts.
NOTE: Caps should be installed so that the
stamped numbers on the caps are in numerical
order, ( 1 thru 4 ) from the front to the rear of the
engine. All caps should be installed so that the
stamped arrows on the caps point toward the front
of the engine.
(4) Working in 1/2 turn increments, tighten the
bearing cap retaining bolts starting with the middle
cap working outward (Fig. 23).
(5) Torque the camshaft bearing cap retaining
bolts to 11 N´m (100 in. lbs.).
KJENGINE - 3.7L 9 - 33
CYLINDER HEAD - RIGHT (Continued)
(6) Position the camshaft drive gear into the tim-
ing chain aligning the V6 mark between the two
marked chain links (Two links marked during remov-
al).
(7) Using Special Tool 8428 Camshaft Wrench,
rotate the camshaft until the camshaft sprocket
dowel is aligned with the slot in the camshaft
sprocket. Install the sprocket onto the camshaft.
CAUTION: Remove excess oil from camshaft
sprocket bolt. Failure to do so can cause bolt over-
torque resulting in bolt failure.
(8) Remove excess oil from camshaft sprocket bolt,
then install the camshaft sprocket retaining bolt and
hand tighten.
(9) Remove timing chain wedge special tool 8379.
(10) Using Special Tool 6958 spanner wrench with
adapter pins 8346, torque the camshaft sprocket
retaining bolt to 122 N´m (90 ft. lbs.).
(11) Install the camshaft position sensor.
(12) Install the cylinder head cover.
CYLINDER HEAD COVER(S)
REMOVAL
(1) Disconnect battery negative cable.
(2) Remove air cleaner assembly, resonator assem-
bly and air inlet hose.
(3) Drain cooling system, below the level of the
heater hoses. Refer to COOLING SYSTEM.(4) Remove accessory drive belt.
(5) Remove air conditioning compressor retaining
bolts and move compressor to the left.
(6) Remove heater hoses.
(7) Disconnect injector and ignition coil connectors.
(8) Disconnect and remove positive crankcase ven-
tilation (PCV) hose.
(9) Remove oil fill tube.
(10) Un-clip injector and ignition coil harness and
move away from cylinder head cover.
(11) Remove right rear breather tube and filter
assembly.
(12) Remove cylinder head cover retaining bolts.
(13) Remove cylinder head cover.
INSTALLATION
CAUTION: Do not use harsh cleaners to clean the
cylinder head covers. Severe damage to covers
may occur.
NOTE: The gasket may be used again, provided no
cuts, tears, or deformation has occurred.
(1) Clean cylinder head cover and both sealing sur-
faces. Inspect and replace gasket as necessary.
(2) Tighten cylinder head cover bolts and double
ended studs to 12 N´m (105 in. lbs).
(3) Install right rear breather tube and filter
assembly.
(4) Connect injector, ignition coil electrical connec-
tors and harness retaining clips.
(5) Install the oil fill tube.
(6) Install PCV hose.
(7) Install heater hoses.
(8) Install air conditioning compressor retaining
bolts.
(9) Install accessory drive belt
(10) Fill Cooling system
(11) Install air cleaner assembly, resonator assem-
bly and air inlet hose.
(12) Connect battery negative cable.
INTAKE/EXHAUST VALVES &
SEATS
STANDARD PROCEDURE - REFACING
NOTE: Valve seats that are worn or burned can be
reworked, provided that correct angle and seat
width are maintained. Otherwise the cylinder head
must be replaced.
Fig. 23 Camshaft Bearing Caps Tightening
Sequence
9 - 34 ENGINE - 3.7LKJ
CAMSHAFT(S) (Continued)
MAIN BEARING JOURNAL DIAMETER
(CRANKSHAFT REMOVED)
Remove the crankshaft from the cylinder block.
Refer to CRANKSHAFT.
Clean the oil off the main bearing journal.
Determine the maximum diameter of the journal
with a micrometer. Measure at two locations 90É
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.
Install the crankshaft into the cylinder block. Refer
to CRANKSHAFT.
Check crankshaft end play. Refer to CHECKING
CRANKSHAFT END PLAY.
CRANKSHAFT MAIN BEARING SELECTION
(1) Service main bearings are available in three
grades. The chart below identifies the three service
grades available.
Crankshaft JOURNAL SIZE
SIZE mm (in.)
MARKING
9R9Size 63.488 - 63.496 mm
(2.4995 - 2.4998 in.)
9S9Size
63.496 - 63.500 mm (2.4998 - 2.4999 in.
9T9Size63.500 - 63.504 mm (2.4999 - 2.501 in.)
Bearing size and application
Bearing
CodeSIze Application
Upper Bearing
A.2.443 - 2.447
mmUse with
Cankshaft size9R9
(.0961 - .0963 in.)
B2.439 - 2.443 mm Use with
crankshaft9S, T9
(0.960 -.o961 in.)
C2.435 - 2.439 mm Use with
carnkshaft9U9
(.0958 - .0960 in.)
Lower Bearing Main919and949
9192.441 - 2.447 mm Use with
carnkshaft9R, S9
(.0961 -.0963 in.)
9292.435 - 2.441 mm Use with
crankshaft9T, U9
(.0958 - .0962 in.)
Crankshaft JOURNAL SIZE
SIZE mm (in.)
MARKING
Lower Main Bearing929and939
9392.429 - 2.435 mm Use with
crankshaft9R, S9
(.0956 - .0958 in.)
9492.423 - 2.429 mm Use with
crankshaft9T, U9
(.0953 - .0956 in.)
Bearing Clearances
Main91, 49
Crankshaft
9R9.004 - .034 mm ( .00015 - .0013 in.)
Crankshaft
9S9.004 - .030 mm ( .00015 - .0011 in.)
Crankshaft
9T9.006 - .032 mm (.0002 - .0012 in.)
Crankshaft
9U9.002 - .032 mm (.00007 -. 0012 in.)
Main92, 39
Crankshaft
9R9.016 - .064 mm (.0 062 - .0025 in.)
Crankshaft
9S9.016 - .042 mm (.00062 - .016 in.)
Crankshaft
9T9.018 - .044 mm (.0007 - .0017 in.)
Crankshaft
9U9.014 - .044 mm (.0005 - .0017 in.)
CRANKSHAFT OIL SEAL -
FRONT
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(3) Remove A/C compressor mouning fasteners and
set aside.
(4) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(5) Remove upper radiator hose.
(6) Disconnect electrical connector for fan mounted
inside radiator shroud.
(7) Remove radiator shroud attaching fasteners.
(8) Remove radiator cooling fan and shroud (Refer
to 7 - COOLING/ENGINE/RADIATOR FAN -
REMOVAL).
(9) Remove crankshaft damper bolt.
9 - 46 ENGINE - 3.7LKJ
CRANKSHAFT MAIN BEARINGS (Continued)
(10) Remove damper using Special Tools 8513
Insert and 1026 Three Jaw Puller (Fig. 45).
(11) Using Special Tool 8511, remove crankshaft
front seal (Fig. 46).INSTALLATION
CAUTION: To prevent severe damage to the Crank-
shaft, Damper or Special Tool 8512, thoroughly
clean the damper bore and the crankshaft nose
before installing Damper.
(1) Using Special Tool 8348 and 8512, install
crankshaft front seal (Fig. 47).
(2) Install vibration damper (Refer to 9 - ENGINE/
ENGINE BLOCK/VIBRATION DAMPER - INSTAL-
LATION).
(3) Install radiator cooling fan and shroud (Refer
to 7 - COOLING/ENGINE/RADIATOR FAN -
INSTALLATION).
(4) Install upper radiator hose.
(5) Install A/C compressor and tighten fasteners to
54 N´m (40 ft. lbs.).
(6) Install accessory drive belt refer (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(7) Refill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(8) Connect negative cable to battery.
Fig. 45 Crankshaft DamperÐRemoval
1 - SPECIAL TOOL 8513 INSERT
2 - SPECIAL TOOL 1026
Fig. 46 Crankshaft Front SealÐRemoval
1 - SPECIAL TOOL 8511
Fig. 47 Crankshaft Front SealÐInstallation
1 - TIMING CHAIN COVER
2 - SPECIAL TOOL 8348
3 - SPECIAL TOOL 8512
KJENGINE - 3.7L 9 - 47
CRANKSHAFT OIL SEAL - FRONT (Continued)
VIBRATION DAMPER
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
NOTE: Transmission cooler line snaps into shroud
lower right hand corner.
(3) Remove crankshaft damper bolt.
(4) Remove damper using Special Tools 8513
Insert and 1026 Three Jaw Puller (Fig. 62).
Fig. 59 Side RailÐInstallation
1 - SIDE RAIL END
Fig. 60 Upper and Intermediate RingsÐInstallation
Fig. 61 Piston Ring End Gap Position
1 - SIDE RAIL UPPER
2 - NO. 1 RING GAP
3 - PISTON PIN
4 - SIDE RAIL LOWER
5 - NO. 2 RING GAP AND SPACER EXPANDER GAP
Fig. 62 Crankshaft DamperÐRemoval
1 - SPECIAL TOOL 8513 INSERT
2 - SPECIAL TOOL 1026
9 - 54 ENGINE - 3.7LKJ
PISTON RINGS (Continued)
CAUTION: The structural cover must be held tightly
against both the engine and the transmission bell
housing during tightening sequence. Failure to do
so may cause damage to the cover.
(4) Starting with the two rear cover-to-engine
bolts, tighten bolts (1) (Fig. 66) to 54 N´m (40 ft. lbs.),
then tighten bolts (2) (Fig. 66) and (3) to 54 N´m ( 40
ft. lbs.) in the sequence shown.
FRONT MOUNT
REMOVAL
(1) Disconnect the negative cable from the battery.
CAUTION: Remove the fan blade, fan clutch and fan
shroud before raising engine. Failure to do so may
cause damage to the fan blade, fan clutch and fan
shroud.
(2) Remove the fan blade, fan clutch and fan
shroud. Refer to COOLING SYSTEM for procedure.
(3) Remove the engine oil filter.
(4) Support the engine with a suitable jack and a
block of wood across the full width of the engine oil
pan.
(5) Remove the four (4) cylinder block-to-insulator
mount bolts and the nut from the engine insulator
mount through bolt.
(6) Using the jack, raise the engine high enough to
remove the engine insulator mount through bolt and
the insulator mount (Fig. 67) and (Fig. 68).
Fig. 65 Structural Cover
1 - BOLT
2 - BOLT
3 - BOLT
Fig. 66 Structural Cover
1 - BOLT
2 - BOLT
3 - BOLT
Fig. 67 Engine Insulator Mount 3.7 Left
1 -MOUNT
2 - NUT
3 - WIRE RETAINER
4 - FASTENER
5 - BOLT
6 - THRU BOLT
9 - 56 ENGINE - 3.7LKJ
STRUCTURAL COVER (Continued)
(11) Bleed fuel system. Refer to FUEL SYSTEM.
(12) Remove fuel rail.
(13) Remove throttle body assembly and mounting
bracket.
(14) Drain cooling system below coolant tempera-
ture level. Refer to COOLING SYSTEM.
(15) Remove the heater hoses from the engine
front cover and the heater core.
(16) Unclip and remove heater hoses and tubes
from intake manifold.
(17) Remove coolant temperature sensor. Refer to
FUEL SYSTEM.
(18) Remove intake manifold retaining fasteners in
reverse order of tightening sequence.
(19) Remove intake manifold.
INSTALLATION
(1) Install intake manifold gaskets.
(2) Install intake manifold.
(3) Install intake manifold retaining bolts and
tighten in sequence shown in to 12 N´m (105 in. lbs.).
(4) Install left and right radio suppressor straps.
(5) Install throttle body assembly.
(6) Install throttle cable bracket.
(7) Connect throttle cable and speed control cable
to throttle body.
(8) Install fuel rail.
(9) Install ignition coil towers.
(10) Position and install heater hoses and tubes
onto intake manifold.
(11) Install the heater hoses to the heater core and
engine front cover.
(12) Connect electrical connectors for the following
components:
²Manifold Absolute Pressure (MAP) Sensor
²Intake Air Temperature (IAT) Sensor
²Throttle Position (TPS) Sensor
²Coolant Temperature (CTS) Sensor
²Idle Air Control (IAC) Motor
²Ignition coil towers
²Fuel injectors
(13) Install top oil dipstick tube retaining bolt and
ground strap.
(14) Connect generator electrical connections.
(15) Connect Vapor purge hose, Brake booster
hose, Speed control servo hose, Positive crankcase
ventilation (PCV) hose.
(16) Fill cooling system.
(17) Install resonator assembly and air inlet hose.
(18) Connect negative cable to battery.
EXHAUST MANIFOLD
DESCRIPTION
The exhaust manifolds (Fig. 87) are log style with
a patented flow enhancing design to maximize perfor-
mance. The exhaust manifolds are made of high sili-
con molybdenum cast iron. A perforated core graphite
exhaust manifold gasket is used to improve sealing
to the cylinder head. The exhaust manifolds are cov-
ered by a three layer laminated heat shield for ther-
mal protection and noise reduction. The heat shields
(Fig. 88) are fastened with a torque prevailing nut
that is backed off slightly to allow for the thermal
expansion of the exhaust manifold.
REMOVAL
RIGHT EXHAUST MANIFOLD
(1) Disconnect the negative cable from the battery.
(2) Raise and support the vehicle.
(3) Remove the bolts and nuts attaching the
exhaust pipe to the engine exhaust manifold.
(4) Lower the vehicle.
(5) Remove the exhaust heat shield (Fig. 89).
(6) Remove bolts, nuts and washers attaching
manifold to cylinder head.
(7) Remove manifold and gasket from the cylinder
head.
Fig. 87 EXHAUST MANIFOLDS
1 - LEFT SIDE EXHAUST MANIFOLD
2 - RIGHT SIDE EXHAUST MANIFOLD
KJENGINE - 3.7L 9 - 69
INTAKE MANIFOLD (Continued)
BALANCE SHAFT
REMOVAL
(1) Remove the primary and secondary timing
chains. Refer to TIMING CHAIN and SPROCKET.
NOTE: The balance shaft and gear are serviced as
an assembly. Do not attempt to remove the gear
from the balance shaft.Remove the retaining bolt
from the counterbalance shaft thrust plate (Fig. 96).
(2) Using Special Tool 8641 Counterbalance shaft
remover/installer tool, remove the counterbalance
shaft from the engine (Fig. 97).
INSTALLATION
NOTE: The balance shaft and gear are serviced as
an assembly. Do not attempt to remove the gear
from the balance shaft.
(1) Coat counterbalance shaft bearing journals
with clean engine oil.
NOTE: The balance shaft is heavy, and care should
be used when installing shaft, so bearings are not
damaged.(2) Using Special Tool 8641 Counterbalance shaft
remover/installer tool, carefully install counterbal-
ance shaft into engine.
(3) Install Counterbalance shaft thrust plate
retaining bolt finger tight.Do not tighten bolt at this
time.
(4) Position the right side of the thrust plate with
the right chain guide bolt, install bolt finger tight.
(5) Torque the thrust plate retaining bolt to 28
N´m (250 in. lbs.).
(6) Remove the chain guide bolt so that guide can
be installed.
TIMING BELT / CHAIN
COVER(S)
REMOVAL
(1) Disconnect the battery negative cable.
(2) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(3) Remove electric cooling fan and fan shroud
assembly.
(4) Remove fan and fan drive assembly (Refer to 7
- COOLING/ENGINE/FAN DRIVE VISCOUS
CLUTCH - REMOVAL).
(5) Disconnect both heater hoses at timing cover.
(6) Disconnect lower radiator hose at engine.
Fig. 95 Camshaft Sprocket V6 Marks
1 - LEFT CYLINDER HEAD
2 - RIGHT CYLINDER HEAD
9 - 74 ENGINE - 3.7LKJ
VALVE TIMING (Continued)