2002 JEEP LIBERTY timing chain sprocket removal

OIL PRESSURE SENSOR/
SWITCH
DESCRIPTION
The 3±wire, solid-state engine oil pressure sensor
(sending unit) is located in an engine oil pressure
gallery.
OPERATION
The oil pressure sensor uses three circuits. They
are:
²A 5±volt power supply from the Powertrain Con-
trol Module (PCM)
²A sensor ground through the PCM's sensor
return
²A signal to the PCM relating to engine oil pres-
sure
The oil pressure sensor has a 3±wire electrical
function very much like the Manifold Absolute Pres-
sure (MAP) sensor. Meaning different pressures
relate to different output voltages.
A 5±volt supply is sent to the sensor from the PCM
to power up the sensor. The sensor returns a voltage
signal back to the PCM relating to engine oil pres-
sure. This signal is then transferred (bussed) to the
instrument panel on either a CCD or PCI bus circuit
(depending on vehicle line) to operate the oil pressure
gauge and the check gauges lamp. Ground for the
sensor is provided by the PCM through a low-noise
sensor return.
REMOVAL
(1) Disconnect the negative cable from the battery.
(2) Raise vehicle on hoist.
(3) Remove front splash shield.
(4) Disconnect oil pressure sender wire (Fig. 78).
(5) Remove the pressure sender (Fig. 78).
INSTALLATION
(1) Install oil pressure sender.
(2) Connect oil pressure sender wire.
(3) Install front splash shield.
(4) Lower vehicle.
(5) Connect the negative battery cable.
OIL PUMP
REMOVAL
(1) Remove the oil pan and pick-up tube (Refer to
9 - ENGINE/LUBRICATION/OIL PAN - REMOVAL).
(2) Remove the timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
(3) Remove the timing chains and tensioners
(Refer to 9 - ENGINE/VALVE TIMING/TIMING
BELT/CHAIN AND SPROCKETS - REMOVAL).
(4) Remove the four bolts, primary timing chain
tensioner and the oil pump.
DISASSEMBLY
(1) Remove oil pump cover screws and lift off cover
plate.
(2) Remove pump inner and outer rotors.
NOTE: Once the oil pressure relief valve, cup plug,
and pin are removed, the pump assembly must be
replaced.
(3) If it is necessary to remove the pressure relief
valve, drive the roll pin from pump housing and
remove cup plug, spring and valve.
Fig. 78 Oil Pressure Sending Unit
1 - BELT
2 - OIL PRESSURE SENSOR
3 - OIL FILTER
4 - ELEC. CONNECTOR
KJENGINE - 3.7L 9 - 65

(5) Using Special Tool 8428 Camshaft Wrench,
rotate the camshaft until the alignment dowel on the
camshaft is aligned with the slot in the camshaft
drive gear.
CAUTION: Remove excess oil from camshaft
sprocket retaining bolt before reinstalling bolt. Fail-
ure to do so may cause over-torqueing of bolt
resulting in bolt failure.
(6) Position the camshaft drive gear onto the cam-
shaft, remove oil from bolt then install the retaining
bolt. Using Special Tools, Spanner Wrench 6958 with
Adapter Pins 8346 and a suitable torque wrench,
Tighten retaining bolt to 122N´m (90 ft. Lbs.).
(7) Remove Special Tool 8379.
(8) Rotate the crankshaft two full revolutions, then
reverify that the camshaft drive gear V6 marks are
in fact aligned.
(9) Install the cylinder head covers. Refer to Cylin-
der Head Cover in this section.
Fig. 92 COUNTERBALANCE SHAFT ALIGNMENT
MARKS
1 - COUNTERBALANCE SHAFT
2 - TIMING MARKS
3 - IDLER SPROCKET
Fig. 93 SECURING TIMING CHAIN TENSIONER
USING TIMING CHAIN WEDGE
1 - CYLINDER HEAD
2 -SPECIAL TOOL 8379
2 - TIMING CHAIN
Fig. 94 CAMSHAFT DRIVE GEAR REMOVAL/INST
1 - SPECIAL TOOL 8279 TIMING CHAIN WEDGE
2 - CAMSHAFT DRIVE GEAR
3 - RETAINING BOLT
4 - CYLINDER HEAD
KJENGINE - 3.7L 9 - 73
VALVE TIMING (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)

IDLER SHAFT
REMOVAL
(1) Remove the primary and secondary timing
chains and sprockets. Refer to procedure in this sec-
tion.
NOTE: To remove the idler shaft, it is necessary to
tap threads into the shaft, to install the removal
tool.
(2) Using a 12 mm X 1.75 tap, cut threads in the
idler shaft center bore.
(3) Cover the radiator core with a suitable cover.
CAUTION: Use care when removing the idler shaft,
Do not strike the radiator cooling fins with the slide
hammer.
(4) Using Special Tool 8517 Slide Hammer, remove
the idler shaft.
INSTALLATION
(1) Thoroughly clean the idler shaft bore.
(2) Position the idler shaft in the bore.
NOTE: The two lubrication holes in the idler shaft
do not require any special alignment.
NOTE: Before using the retaining bolt to install the
idler shaft, coat the threads and the pilot on the
idler shaft, with clean engine oil.
(3) Using the primary idler sprocket retaining bolt
and washer, carefully draw the idler shaft into the
bore until fully seated.
(4) Coat the idler shaft with clean engine oil.
(5) Install the timing chains and sprockets. Refer
to procedure in this section.
TIMING BELT/CHAIN AND
SPROCKET(S
REMOVAL
(1) Disconnect negative cable from battery.
(2) Drain cooling system. Refer to COOLING SYS-
TEM for procedures.
(3) Remove right and left cylinder head covers.
Refer to CYLINDER HEAD COVER.
(4) Remove radiator fan shroud. Refer to COOL-
ING SYSTEM for procedure.
(5) Rotate engine until timing mark on crankshaft
damper aligns with TDC mark on timing chain cover
(Fig. 103) (#1 cylinder exhaust stroke) and the cam-
shaft sprocket ªV6º marks are at the 12 o'clock posi-
tion (Fig. 102).
CAUTION: The nut on the right side camshaft
sprocket should not be removed for any reason, as
the sprocket and camshaft sensor target wheel is
serviced as an assembly. If the nut was removed
retorque nut to 5 N´m (44 in. lbs.).
(6) Remove power steering pump. Refer to STEER-
ING for procedure.
(7) Remove access plug from left and right cylinder
heads for access to chain guide fasteners (Fig. 104).
(8) Remove the oil fill housing to gain access to the
right side tensioner arm fastener.
(9) Remove crankshaft damper and timing chain
cover. Refer to procedures.
(10) Collapse and pin primary chain tensioner.
CAUTION: Plate behind left secondary chain ten-
sioner could fall into oil pan. Therefore, cover pan
opening.
(11) Remove secondary chain tensioners.
(12) Remove camshaft position and crankshaft
position sensors (Fig. 105) and (Fig. 106).
KJENGINE - 3.7L 9 - 77

CRANKSHAFT
DESCRIPTION.........................32
OPERATION...........................33
STANDARD PROCEDURE - CRANKSHAFT
ENDPLAY ...........................33
REMOVAL.............................33
INSPECTION..........................34
INSTALLATION.........................34
CRANKSHAFT MAIN BEARINGS
STANDARD PROCEDURE - MAIN BEARING -
FITTING.............................35
CRANKSHAFT OIL SEAL - FRONT
REMOVAL.............................37
INSTALLATION.........................37
CRANKSHAFT OIL SEAL - REAR
REMOVAL.............................38
INSTALLATION.........................39
PISTON & CONNECTING ROD
DESCRIPTION.........................40
OPERATION...........................40
REMOVAL.............................40
INSTALLATION.........................41
PISTON RINGS
STANDARD PROCEDURE
PISTON RING - FITTING................42
VIBRATION DAMPER
REMOVAL.............................43
INSTALLATION.........................43
STRUCTURAL COLLAR
REMOVAL.............................44
INSTALLATION.........................44
ENGINE MOUNTING
DESCRIPTION.........................44
FRONT MOUNT
REMOVAL.............................44
INSTALLATION.........................44
REAR MOUNT
REMOVAL.............................45
INSTALLATION.........................45
LUBRICATION
DESCRIPTION.........................46
OPERATION...........................46
DIAGNOSIS AND TESTING - ENGINE OIL
PRESSURE CHECKING.................46
OIL
STANDARD PROCEDURE
ENGINE OIL LEVEL CHECK.............47
STANDARD PROCEDURE - ENGINE OIL
AND FILTER CHANGE..................47
OIL FILTER
DESCRIPTION.........................47
REMOVAL.............................47
INSTALLATION.........................47
OIL PAN
REMOVAL.............................48INSTALLATION.........................48
OIL PRESSURE SENSOR/SWITCH
DESCRIPTION.........................48
OPERATION...........................48
OIL PUMP
REMOVAL.............................49
DISASSEMBLY.........................49
CLEANING............................49
INSPECTION..........................50
ASSEMBLY............................50
INSTALLATION.........................50
INTAKE MANIFOLD
DESCRIPTION.........................51
OPERATION...........................51
DIAGNOSIS AND TESTING - INTAKE
MANIFOLD LEAKS.....................51
REMOVAL.............................52
INSPECTION..........................52
INSTALLATION.........................52
EXHAUST MANIFOLD
DESCRIPTION.........................53
OPERATION...........................53
REMOVAL.............................53
CLEANING............................53
INSPECTION..........................53
INSTALLATION.........................53
TIMING BELT COVER(S)
REMOVAL.............................53
INSTALLATION.........................53
TIMING BELT AND SPROCKET(S)
REMOVAL
REMOVAL - TIMING BELT...............55
REMOVAL - CRANKSHAFT SPROCKET....55
CLEANING............................55
INSTALLATION
INSTALLATION - CRANKSHAFT SPROCKET . 56
INSTALLATION - TIMING BELT...........56
TIMING BELT TENSIONER & PULLEY
REMOVAL.............................59
INSTALLATION.........................59
BALANCE SHAFT
DESCRIPTION.........................59
OPERATION...........................59
REMOVAL.............................60
INSTALLATION
BALANCE SHAFT TIMING...............61
BALANCE SHAFT CARRIER
REMOVAL.............................64
INSTALLATION.........................64
BALANCE SHAFT CHAIN
REMOVAL.............................64
INSTALLATION.........................64
9s - 2 ENGINEKJ

Possible indications of the cylinder head gasket
leaking between a cylinder and an adjacent water
jacket are:
²Engine overheating
²Loss of coolant
²Excessive steam (white smoke) emitting from
exhaust
²Coolant foaming
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is
leaking between adjacent cylinders, follow the proce-
dures in Cylinder Compression Pressure Test (Refer
to 9 - ENGINE - DIAGNOSIS AND TESTING). An
engine cylinder head gasket leaking between adja-
cent cylinders will result in approximately a 50±70%
reduction in compression pressure.
CYLINDER-TO-WATER JACKET LEAKAGE TEST
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING WITH COOLANT PRES-
SURE CAP REMOVED.
VISUAL TEST METHOD
With the engine cool, remove the coolant pressure
cap. Start the engine and allow it to warm up until
thermostat opens.
If a large combustion/compression pressure leak
exists, bubbles will be visible in the coolant.
COOLING SYSTEM TESTER METHOD
WARNING: WITH COOLING SYSTEM TESTER IN
PLACE, PRESSURE WILL BUILD UP FAST. EXCES-
SIVE PRESSURE BUILT UP, BY CONTINUOUS
ENGINE OPERATION, MUST BE RELEASED TO A
SAFE PRESSURE POINT. NEVER PERMIT PRES-
SURE TO EXCEED 138 kPa (20 psi).
Install Cooling System Tester 7700 or equivalent to
pressure cap neck. Start the engine and observe the
tester's pressure gauge. If gauge pulsates with every
power stroke of a cylinder a combustion pressure
leak is evident.
CHEMICAL TEST METHOD
Combustion leaks into the cooling system can also
be checked by using Bloc-Chek Kit C-3685-A or
equivalent. Perform test following the procedures
supplied with the tool kit.
REMOVAL - CYLINDER HEAD
(1) Perform fuel system pressure release procedure
before attempting any repairs.(Refer to 14 -FUEL SYSTEM/FUEL DELIVERY - SPECIFICA-
TIONS)
(2) Disconnect battery negative cable.
(3) Drain cooling system. (Refer to 7 - COOLING -
STANDARD PROCEDURE)
(4) Remove air filter housing and inlet tube.
(5) Remove intake manifold.
(6) Remove heater tube support bracket from cyl-
inder head.
(7) Disconnect radiator upper and heater supply
hoses from water outlet connections.
(8) Remove accessory drive belts. (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL)
(9) Raise vehicle and remove exhaust pipe from
manifold.
(10) Remove power steering pump and set aside.
Do not disconnect lines.
(11) Remove accessory drive bracket
(12) Remove ignition coil and wires from engine.
(13) Disconnect cam sensor and fuel injector wir-
ing connectors.
(14) Remove timing belt and camshaft sprockets.
(Refer to 9 - ENGINE/VALVE TIMING/TIMING
BELT/CHAIN AND SPROCKETS - REMOVAL)
(15) Remove timing belt idler pulley and rear tim-
ing belt cover. (Refer to 9 - ENGINE/VALVE TIM-
ING/TIMING BELT / CHAIN COVER(S) -
REMOVAL)
(16) Remove cylinder head cover. (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL)
(17) Remove camshafts (Refer to 9 - ENGINE/
CYLINDER HEAD/CAMSHAFT(S) - REMOVAL).
NOTE: Identify rocker arm position to ensure cor-
rect re-installation in original position, if reused.
(18) Remove rocker arms. (Refer to 9 - ENGINE/
CYLINDER HEAD/ROCKER ARMS - REMOVAL).
(19) Remove cylinder head bolts in REVERSE
sequence of tightening.
(20) Remove cylinder head from engine block.
(21) Inspect and clean cylinder head. (Refer to 9 -
ENGINE/CYLINDER HEAD - INSPECTION) (Refer
to 9 - ENGINE/CYLINDER HEAD - CLEANING)
CLEANING
To ensure engine gasket sealing, proper surface
preparation must be performed, especially with the
use of aluminum engine components and multi-layer
steel cylinder head gaskets.
NOTE: Multi-Layer Steel (MLS) head gaskets require
a scratch free sealing surface.
9s - 20 ENGINEKJ
CYLINDER HEAD (Continued)

²Third All to 68 N´m (50 ft. lbs.)
CAUTION: Do not use a torque wrench for the fol-
lowing step.
²Fourth Turn an additional 1/4 Turn,
(5) Install rocker arms. (Refer to 9 - ENGINE/
CYLINDER HEAD/ROCKER ARMS - INSTALLA-
TION)
(6) Install camshafts. (Refer to 9 - ENGINE/CYL-
INDER HEAD/CAMSHAFT(S) - INSTALLATION).
(7) Install cylinder head cover. (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION)
(8) Install timing belt rear cover and timing belt
idler pulley. (Refer to 9 - ENGINE/VALVE TIMING/
TIMING BELT / CHAIN COVER(S) - INSTALLA-
TION)
(9) Install timing belt and camshaft sprockets.
(Refer to 9 - ENGINE/VALVE TIMING/TIMING
BELT/CHAIN AND SPROCKETS - INSTALLATION)
(10) Connect cam sensor and fuel injectors wiring
connectors.(11) Install ignition coil and wires. Connect igni-
tion coil wiring connector.
(12) Install accessary drive bracket.
(13) Install power steering pump to cylinder head.
(14) Raise vehicle and install the exhaust pipe to
the manifold.
(15) Install accessory drive belts. (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION)
(16) Install heater tube support bracket to cylinder
head.
(17) Install intake manifold.
(18) Connect all vacuum lines, electrical wiring,
ground straps and fuel line.
(19) Fill cooling system. (Refer to 7 - COOLING -
STANDARD PROCEDURE)
(20) Connect battery negative cable.
CAMSHAFT OIL SEAL(S)
REMOVAL
(1) Remove timing belt. (Refer to 9 - ENGINE/
VALVE TIMING/TIMING BELT/CHAIN AND
SPROCKETS - REMOVAL)
(2) Hold each camshaft sprocket with Special Tool
6847 while removing center bolt (Fig. 12).
(3) Remove camshaft sprockets.
(4) Remove exhaust camshaft target ring.
(5) Remove exhaust camshaft sensor.
CAUTION: Inspect sensor and target ring for exces-
sive wear. Clean sensor face and install new spacer
pad.
(6) Remove rear timing belt cover. (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL)
(7) Remove camshaft seal using Special Tool
C-4679-A (Fig. 13).
CAUTION: Do not nick shaft seal surface or seal
bore.
INSTALLATION
NOTE: Clean and inspect sensor and target ring for
excessive wear. Clean sensor face and always
install a new spacer pad.
(1) Shaft seal surface must be free of varnish, dirt
or nicks. Polish with 400 grit paper if necessary.
(2) Install camshaft seals into cylinder head using
Special Tool MD-998306 until flush with head (Fig.
14).
Fig. 10 Cylinder Head Gasket Positioning
1 - PART NUMBER FACES UP
2 - NO. 1 CYLINDER
Fig. 11 Cylinder Head Tightening Sequence
9s - 22 ENGINEKJ
CYLINDER HEAD (Continued)

(3) Install timing belt rear cover. (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION)
NOTE: Target ring tab should provide posative
snap-on fit on the camshaft.
(4) Install exhaust camshaft target ring with the
wordFRONTfacing forward.
(5) Install exhaust camshaft sensor.
(6) Install camshaft sprockets. Hold each sprocket
with Special Tool 6847 and tighten center bolt to 101
N´m (75 ft. lbs.).
(7) Install timing belt and front covers. (Refer to 9
- ENGINE/VALVE TIMING/TIMING BELT/CHAINAND SPROCKETS - INSTALLATION) (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION)
CAMSHAFT(S)
DESCRIPTION
Both nodular iron camshafts have six bearing jour-
nal surfaces and two cam lobes per cylinder (Fig. 15).
Flanges at the rear journals control camshaft end
play. Provision for a cam position sensor is located on
the exhaust camshaft on the front of the cylinder
head. A hydrodynamic oil seal is used for oil control
at the front of the camshaft.
OPERATION
The camshaft is driven by the crankshaft via drive
sprockets and belt. The camshaft has precisely
machined lobes to provide accurate valve timing and
duration.
STANDARD PROCEDURE - CAMSHAFT
END-PLAY
(1) Oil camshaft journals and install camshaft
WITHOUTcam follower assemblies. Install rear cam
caps and tighten screws to specified torque.
(2) Using a suitable tool, move camshaft as far
rearward as it will go.
(3) Zero dial indicator (Fig. 16).
(4) Move camshaft as far forward as it will go.
(5) Record reading on dial indicator. For end play
specification, (Refer to 9 - ENGINE - SPECIFICA-
TIONS).
(6) If end play is excessive, check cylinder head
and camshaft for wear; replace as necessary.
Fig. 12 Camshaft Sprocket - Removal/Installation
1 - SPECIAL TOOL 6847
Fig. 13 Camshaft Oil Seal - Removal With C-4679-A
1 - SPECIAL TOOL C-4679
Fig. 14 Camshaft Seal - Installation
1 - SPECIAL TOOL MD 998306
KJENGINE9s-23
CAMSHAFT OIL SEAL(S) (Continued)