cli JEEP GRAND CHEROKEE 2002 WJ / 2.G Owners Manual

(12) Install the push rods, rocker arms, pivots and
bridges in the order they were removed (Refer to 9 -
ENGINE/CYLINDER HEAD/ROCKER ARM /
ADJUSTER ASSY - INSTALLATION).
(13) Install the engine cylinder head cover (Refer
to 9 - ENGINE/CYLINDER HEAD/CYLINDER
HEAD COVER(S) - INSTALLATION).
(14) Attach the air conditioner compressor mount-
ing bracket to the engine cylinder head and block.
Tighten the bolts to 40 N´m (30 ft. lbs.) torque.
(15) Attach the air conditioning compressor to the
bracket. Tighten the bolts to 27 N´m (20 ft. lbs.)
torque.
CAUTION: The serpentine drive belt must be routed
correctly. Incorrect routing can cause the water
pump to turn in the opposite direction causing the
engine to overheat.
(16) Install the serpentine drive belt. (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(17) Install the air cleaner and ducting.
(18) Connect the hoses to the engine thermostat
housing and fill the cooling system to the specified
level (Refer to 7 - COOLING - STANDARD PROCE-
DURE).
(19) The automatic transmission throttle linkage
and cable must be adjusted after completing the
engine cylinder head installation (Refer to 21 -
TRANSMISSION/TRANSAXLE/AUTOMATIC - AW4/
THROTTLE VALVE CABLE - ADJUSTMENTS).
(20) Install the temperature sending unit and con-
nect the wire connector.
(21) If equipped with air conditioning, install A/C
compressor (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING/A/C COMPRESSOR -
INSTALLATION) and charge A/C system (Refer to 24
- HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE).
(22) Connect negative cable to battery.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN DIRECT
LINE WITH THE FAN. DO NOT PUT HANDS NEAR
THE PULLEYS, BELTS OR FAN. DO NOT WEAR
LOOSE CLOTHING.
(23) Operate the engine with the radiator cap off.
Inspect for leaks and continue operating the engine
until the engine thermostat opens. Add coolant, if
required.CYLINDER HEAD COVER(S)
DESCRIPTION
The cylinder head cover (Fig. 11) is made of
stamped steel and incorporates the Crankcase Venti-
lation (CCV) Hoses and the oil fill opening.
REMOVAL
The cylinder head cover is isolated from the cylin-
der head via grommets and a reusable molded rubber
gasket. The grommet and limiter are retained in the
cylinder head cover.
(1) Disconnect negative cable from battery.
(2) Disconnect the Crankcase Ventilation (CCV)
vacuum hose from engine cylinder head cover.
(3) Disconnect the fresh air inlet hose from the
engine cylinder head cover.
(4) Disconnect the accelerator, transmission, and
speed (if equipped) control cables from the throttle
body (Fig. 12).
(5) Remove the three bolts that fasten the control
cable bracket to the intake manifold.
(6) Remove control cables from cylinder head cover
clip.
(7) Position control cables and bracket away from
cylinder head cover secure with tie straps.
(8) Remove the engine cylinder head cover mount-
ing bolts.
(9) Remove the engine cylinder head cover and
gasket.
Fig. 11 Cylinder Head Cover
9 - 22 ENGINE - 4.0LWJ
CYLINDER HEAD (Continued)

CLEANING
Remove any original sealer from the cover sealing
surface of the engine cylinder head and clean the
surface using a fabric cleaner.
Remove all residue from the sealing surface using
a clean, dry cloth.
INSPECTION
Inspect the engine cylinder head cover for cracks.
Replace the cover, if cracked.
The original dark grey gasket material should
NOT be removed. If sections of the gasket material
are missing or are compressed, replace the engine
cylinder head cover. However, sections with minor
damage such as small cracks, cuts or chips may be
repaired with a hand held applicator. The new mate-
rial must be smoothed over to maintain gasket
height. Allow the gasket material to cure prior to
engine cylinder head cover installation.
INSTALLATION
The cylinder head cover is isolated from the cylin-
der head via grommets and a reusable molded rubber
gasket. The grommet and limiter are retained in the
cylinder head cover.
(1) If a replacement cover is installed, transfer the
CCV valve grommet and oil filler cap from the origi-
nal cover to the replacement cover.
(2) Install cylinder head cover and gasket (Fig. 13).
Tighten the mounting bolts to 10 N´m (85 in. lbs.)
torque.
(3) Connect the CCV hoses.(4) Install control cables and bracket on intake
manifold and tighten bolts to 8.7 N´m (77 in. lbs.)
torque.
(5) Connect control cables to throttle body linkage.
(6) Snap control cables into cylinder head cover
clip.
(7) Connect negative cable to battery.
INTAKE/EXHAUST VALVES &
SEATS
DESCRIPTION
The valves are made of heat resistant steel and
have chrome plated stems to prevent scuffing. All
valves use three bead locks to promote valve rotation
(Fig. 14).
STANDARD PROCEDURE - VALVE SERVICE
VALVE REFACING
Clean all carbon deposits from the combustion
chambers, valve ports, valve stems, valve stem
guides and head.
(1) Use a valve refacing machine to reface the
intake and exhaust valves to the specified angle.
(2) After refacing, a margin of at least 0.787 mm
(0.031 inch) must remain (Fig. 15). If the margin is
less than 0.787 mm (0.031 inch), the valve must be
replaced.
VALVE SEAT REFACING
Clean all carbon deposits from the combustion
chambers, valve ports, valve stems, valve stem
guides and head.
(1) Install a pilot of the correct size in the valve
guide bore. Reface the valve seat to the specified
angle with a good dressing stone. Remove only
enough metal to provide a smooth finish.
(2) Use tapered stones to obtain the specified seat
width when required.
Fig. 12 Engine Cylinder Head Cover
1 - TRANS CONTROL CABLE
2 - ACCELERATOR CABLE
3 - CONTROL CABLE BRACKET
4 - CYLINDER HEAD COVER
Fig. 13 Cylinder Head Cover Gasket Locator Pins at
#8
WJENGINE - 4.0L 9 - 23
CYLINDER HEAD COVER(S) (Continued)

AIR CLEANER ELEMENT
REMOVAL - 4.7L
(1) Unlatch four clips retaining air cleaner cover to
air cleaner housing (Fig. 8).
(2) Lift cover up and position to the side.
(3) Remove air cleaner element.
INSTALLATION - 4.7L
(1) Clean inside of air cleaner housing before
installing new element.
(2) Install air cleaner element into housing.
(3) Latch clips and clamp cover down to secure. Be
sure air cleaner cover is properly seated to air
cleaner housing.
Valve Spring Tester C-647
Dial Indicator C-3339
Valve Spring Compressor C-3422-B
Bore Size Indicator C-119
Oil Pressure Gauge C-3292
Piston Ring Compressor C-385
Pressure Tester Kit 7700
Bloc±Chek±Kit C-3685±A
WJENGINE - 4.7L 9 - 83
ENGINE - 4.7L (Continued)

AIR CLEANER HOUSING
REMOVAL - 4.7L
(1) Disconnect air cleaner cover-to-air duct clamp
(Fig. 8).
(2) Disconnect air duct at housing.
(3)Each of the 3 air cleaner housing mount-
ing bolts is attached with 2 nuts (an upper nut
and lower nut). DO NOT REMOVE BOLTS. To
prevent stripping bolts, only remove lower
nuts. The lower housing nuts are located under
left front inner fender (Fig. 8).
(a) To gain access to lower nuts, raise vehicle.
(b) Remove clips retaining rubber inner fender
shield.
(c) Pry back shield enough to gain access to
lower nuts.
(d) Remove 3 nuts.(e) Remove air cleaner assembly from vehicle.
(4) If resonator is to be removed, disconnect
breather tube at resonator, disconnect air duct clamp
at resonator (Fig. 8)and remove 2 resonator mount-
ing bolts (at sides of resonator). Remove resonator
from throttle body by loosening clamp at throttle
body.
INSTALLATION - 4.7L
(1) Position air cleaner assembly to body and
install 3 nuts. Tighten nuts to 10 N´m (93 in. lbs.)
torque.To prevent excessive vibration transmit-
ted through housing, the nuts must be properly
torqued. Do not overtighten nuts.
(2) If resonator was removed: Install resonator and
bolts. Tighten bolts to 4 N´m (35 in. lbs.) torque.
Tighten clamp at throttle body to 4 N´m (35 in. lbs.)
torque.
(3) Position fender liner and install clips.
(4) Connect air duct at housing (Fig. 8).
(5) Tighten air duct clamp.
CYLINDER HEAD - LEFT
DESCRIPTION
DESCRIPTION - CYLINDER HEAD
The cylinder heads are made of an aluminum alloy.
The cylinder head features two valves per cylinder
with pressed in powdered metal valve guides. The
cylinder heads also provide enclosures for the timing
chain drain, necessitating unique left and right cylin-
der heads.
DESCRIPTION - VALVE GUIDES
The valve guides are made of powered metal and
are pressed into the cylinder head. The guides are
not replaceable or serviceable, and valve guide ream-
ing is not recommended. If the guides are worn
beyond acceptable limits, replace the cylinder heads.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - HYDRAULIC LASH
ADJUSTER
A tappet-like noise may be produced from several
items. Check the following items.
(1) Engine oil level too high or too low. This may
cause aerated oil to enter the adjusters and cause
them to be spongy.
(2) Insufficient running time after rebuilding cylin-
der head. Low speed running up to 1 hour may be
required.
Fig. 8 Air Cleaner Assembly - 4.7L
1 - AIR DUCT
2 - CLAMPS
3 - AIR CLEANER COVER
4 - CLIPS
5 - HOUSING
6 - HOUSING BOLTS (3)
7 - LOWER HOUSING NUTS (3)
8 - RESONATOR BOLTS
9 - RESONATOR
9 - 84 ENGINE - 4.7LWJ
AIR CLEANER ELEMENT (Continued)

CYLINDER HEAD COVER(S) -
LEFT
DESCRIPTION
The cylinder head covers are made of die cast mag-
nesium, and are not interchangeable from side-to-
side. It is imperative that nothing rest on the
cylinder head covers. Prolonged contact with other
items may wear a hole in the cylinder head cover.
REMOVAL - LEFT SIDE
(1) Disconnect negative cable from battery.
(2) Remove the resonator assemble and air inlet
hose.
(3) Disconnect injector connectors and un-clip the
injector harness.
(4) Route injector harness in front of cylinder head
cover.
(5) Disconnect the left side breather tube and
remove the breather tube.(6) Remove the cylinder head cover mounting
bolts.
(7) Remove cylinder head cover and gasket.
NOTE: The gasket may be used again, provided no
cuts, tears, or deformation has occurred.
CLEANING
Clean cylinder head cover gasket surface.
Clean head rail, if necessary.
INSTALLATIONÐLEFT SIDE
CAUTION: Do not use harsh cleaners to clean the
cylinder head covers. Severe damage to covers
may occur.
CAUTION: DO NOT allow other components includ-
ing the wire harness to rest on or against the cylin-
der head cover. Prolonged contact with other
objects may wear a hole in the engine cylinder head
cover.
(1) Clean cylinder head cover and both sealing sur-
faces. Inspect and replace gasket as necessary.
(2) Install cylinder head cover and hand start all
fasteners. Verify that all studs are in the correct loca-
tion shown in (Fig. 22).
(3) Tighten cylinder head cover bolts and double
ended studs to 12 N´m (105 in. lbs.).
(4) Install left side breather and connect breather
tube.
(5) Connect injector electrical connectors and injec-
tor harness retaining clips.
(6) Install the resonator and air inlet hose.
(7) Connect negative cable to battery.
Fig. 21 Tightening Left Side Cam Sprocket
Retaining Bolt
1 - TORQUE WRENCH
2 - CAMSHAFT SPROCKET
3 - LEFT CYLINDER HEAD
4 - SPECIAL TOOL 6958 SPANNER WITH ADAPTER PINS 8346
Fig. 22 Cylinder Head CoverÐLeft
ITEM DESCRIPTION TORQUE
1 Cover Fasteners 12 N´m (105 in. lbs.)
WJENGINE - 4.7L 9 - 93
CAMSHAFT(S) - LEFT (Continued)

CYLINDER HEAD COVER(S) -
RIGHT
DESCRIPTION
The cylinder head covers are made of die cast mag-
nesium, and are not interchangeable from side-to-
side. It is imperative that nothing rest on the
cylinder head covers. Prolonged contact with other
items may wear a hole in the cylinder head cover.
REMOVAL - RIGHT SIDE
(1) Disconnect battery negative cable.
(2) Remove air cleaner assembly, resonator assem-
bly and air inlet hose.
(3) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(4) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(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.
NOTE: The gasket may be used again, provided no
cuts, tears, or deformation has occurred.
CLEANING
Clean cylinder head cover gasket surface.
Clean head rail, if necessary.
INSTALLATION - RIGHT SIDE
CAUTION: Do not use harsh cleaners to clean the
cylinder head covers. Severe damage to covers
may occur.
CAUTION: DO NOT allow other components includ-
ing the wire harness to rest on or against the
engine cylinder head cover. Prolonged contact with
other objects may wear a hole in the cylinder head
cover.
(1) Clean cylinder head cover and both sealing sur-
faces. Inspect and replace gasket as necessary.(2) Install cylinder head cover and hand start all
fasteners. Verify that all double ended studs are in
the correct location shown in (Fig. 38).
(3) Tighten cylinder head cover bolts and double
ended studs to 12 N´m (105 in. lbs).
(4) Install right rear breather tube and filter
assembly.
(5) Connect injector, ignition coil electrical connec-
tors and harness retaining clips.
(6) Install the oil fill tube.
(7) Install PCV hose.
(8) Install heater hoses.
(9) Install air conditioning compressor retaining
bolts.
(10) Install accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(11) Fill Cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(12) Install air cleaner assembly, resonator assem-
bly and air inlet hose.
(13) Connect battery negative cable.
INTAKE/EXHAUST VALVES &
SEATS
DESCRIPTION
The valves are made of heat resistant steel and
have chrome plated stems to prevent scuffing. Each
valve is actuated by a roller rocker arm which pivots
on a stationary lash adjuster. All valves use three
bead lock keepers to retain the springs and promote
valve rotation.
Fig. 38 Cylinder Head CoverÐRight
ITEM DESCRIPTION TORQUE
1 Cover Fasteners 12 N´m (105 in. lbs.)
9 - 104 ENGINE - 4.7LWJ

(5) With a wiping cloth, clean the gasket sealing
surface of oil and grime.
INSTALLATION
(1) Lightly lubricate oil filter gasket with engine
oil.
(2) Thread filter onto adapter nipple. When gasket
makes contact with sealing surface, (Fig. 94)hand
tighten filter one full turn, do not over tighten.
(3) Add oil, verify crankcase oil level and start
engine. Inspect for oil leaks.
OIL PAN
DESCRIPTION
The engine oil pan is made of laminated steel and
has a single plane sealing surface. The sandwich
style oil pan gasket has an integrated windage tray
and steel carrier. The sealing area of the gasket is
molded with rubber and is designed to be reused as
long as the gasket is not cut, torn or ripped.
REMOVAL
(1) Disconnect negative cable from battery.
(2) Raise vehicle on hoist.
(3) Remove structural cover (Refer to 9 - ENGINE/
ENGINE BLOCK/STRUCTURAL COVER - REMOV-
AL).
(4) Remove exhaust system Y-pipe.
(5) Remove starter (Refer to 8 - ELECTRICAL/
STARTING/STARTER MOTOR - REMOVAL).
(6) Drain engine oil.
(7) Un-clip transmission lines from support on oil
pan stud. Move lines for oil pan clearance.
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 lowering oil pan.
Gasket can not be removed with oil pan.
(8) Remove oil pan bolts and oil pan.
(9) Remove oil pump pickup tube.
(10) Remove oil pan gasket.
CLEANING
(1) Clean oil pan in solvent and wipe dry with a
clean cloth.
(2) Clean the oil pan gasket surface.DO NOTuse
a grinder wheel or other abrasive tool to clean seal-
ing surface.
(3) Clean oil screen and tube thoroughly in clean
solvent.
INSPECTION
(1) Inspect oil drain plug and plug hole for
stripped or damaged threads. Repair as necessary.
(2) Inspect the oil pan mounting flange for bends
or distortion. Straighten flange, if necessary.
INSTALLATION
(1) Clean oil pan and all sealing surfaces. Inspect
oil pan gasket and replace as necessary.
(2) Install oil pan gasket.
Fig. 93 Oil Filter - 4.7L Engine
1 - ENGINE OIL FILTER
Fig. 94 Oil Filter Sealing SurfaceÐTypical
1 - SEALING SURFACE
2 - RUBBER GASKET
3 - OIL FILTER
9 - 132 ENGINE - 4.7LWJ
OIL FILTER (Continued)

(5) Remove nuts attaching upper edge of fascia to
quarter panel and wheel liner (Fig. 4).
(6) Remove plastic push pins attaching fascia to
liftgate opening (Fig. 5).
(7) Remove screws attaching fascia to liftgate
opening.
(8) Remove D pillar trim and scuff plate outboard
screws.
(9) Remove the rearward tie down screws and the
aperture trim panel.
(10) Carefully peel back the rubber body sealer
patch to access the retainer clips.
(11) Release the forward and rearward retainer
clips on both sides of the fascia.
(12) Grasp forward edges of fascia and pull out-
ward to disengage retainers attaching fascia to quar-
ter panel (Fig. 6).
(13) Separate fascia from vehicle.
Fig. 5 Rear Fascia
1 - ABSORBER
2 - RIVET3 - FASCIA
4 - PLASTIC PUSH PIN
Fig. 4 Rear Fascia Attachment
1 - FASCIA
2 - PLASTIC PUSH PIN
WJFRAME & BUMPERS 13 - 3
REAR FASCIA (Continued)

STANDARD PROCEDURE - FUEL SYSTEM
PRESSURE RELEASE
Use following procedure if the fuel injector
rail is, or is not equipped with a fuel pressure
test port.
(1) Remove fuel fill cap.
(2) Remove fuel pump relay from Power Distribu-
tion Center (PDC). For location of relay, refer to label
on underside of PDC cover.
(3) Start and run engine until it stalls.
(4) Attempt restarting engine until it will no
longer run.
(5) Turn ignition key to OFF position.
CAUTION: Steps 1, 2, 3 and 4 must be performed to
relieve high pressure fuel from within fuel rail. Do
not attempt to use following steps to relieve this
pressure as excessive fuel will be forced into a cyl-
inder chamber.
(6) Unplug connector from any fuel injector.
(7) Attach one end of a jumper wire with alligator
clips (18 gauge or smaller) to either injector terminal.(8) Connect other end of jumper wire to positive
side of battery.
(9) Connect one end of a second jumper wire to
remaining injector terminal.
CAUTION: Powering an injector for more than a few
seconds will permanently damage the injector.
(10) Momentarily touch other end of jumper wire
to negative terminal of battery for no more than a
few seconds.
(11) Place a rag or towel below fuel line quick-con-
nect fitting at fuel rail.
(12) Disconnect quick-connect fitting at fuel rail.
Refer to Quick-Connect Fittings.
(13) Return fuel pump relay to PDC.
(14) One or more Diagnostic Trouble Codes (DTC's)
may have been stored in PCM memory due to fuel
pump relay removal. The DRBtscan tool must be
used to erase a DTC.
SPECIFICATIONS
FUEL SYSTEM PRESSURE
339 kPa   34 kPa (49.2 psi   5 psi).
TORQUE - FUEL DELIVERY
DESCRIPTION N-m Ft. Lbs. In. Lbs.
Accelerator Pedal Bracket Mounting Nuts
(without adjustable pedals)12  2 - 105  20
Fuel Filter/Fuel Press. Reg. Bolts 3 - 26
Fuel Hose Clamps 3 - 26
Fuel Injector Rail Mounting Bolts -4.0L Engine 11 - 100
Fuel Injector Rail Mounting Bolts -4.7L V-8
Engine11 - 100
Fuel Pump Module Locknut 74 55 -
Fuel Tank Filler Tube-to-Body Mounting Bolts 2 - 15
Fuel Tank-to-Body Mounting Bolts 88 65 -
Fuel Tank Support Bracket Bolts (large brackets) 88 65 -
Fuel Tank Support Bracket Bolts (small bracket) 5 - 45
Fuel Tank Support Bracket Nuts (large brackets) 61 45 -
Fuel Tank Heat Shield Nuts (shield-to-tank) 9 - 85
Fuel Tank Heat Shield Nuts (shield-to-body) 3 - 25
14 - 4 FUEL DELIVERYWJ
FUEL DELIVERY (Continued)

CAUTION: The left and right fuel rails are replaced
as an assembly. Do not attempt to separate rail
halves at connector tube (Fig. 22). Due to design of
tube, it does not use any clamps. Never attempt to
install a clamping device of any kind to tube. When
removing fuel rail assembly for any reason, be care-
ful not to bend or kink tube.
(1) Remove fuel tank filler tube cap.
(2) Perform Fuel System Pressure Release Proce-
dure.
(3) Remove negative battery cable at battery.
(4) Remove air duct at throttle body air box.
(5) Remove air box at throttle body.
(6) Remove wiring at rear of generator.
(7) Disconnect fuel line latch clip and fuel line at
fuel rail. A special tool will be necessary for fuel line
disconnection. Refer to Quick-Connect Fittings.
(8) Remove vacuum lines at throttle body.(9) Disconnect electrical connectors at all 8 fuel
injectors. To remove connector refer to (Fig. 23). Push
red colored slider away from injector (1). While push-
ing slider, depress tab (2) and remove connector (3)
from injector. The factory fuel injection wiring har-
ness is numerically tagged (INJ 1, INJ 2, etc.) for
injector position identification. If harness is not
tagged, note wiring location before removal.
(10) Disconnect electrical connectors at throttle
body.
(11) Disconnect electrical connectors at MAP and
IAT sensors.
Fig. 21 Fuel Injector Rail/Fuel DamperÐ4.0L Engine
1 - INJ. #1
2 - INJ. #2
3 - INJ. #3
4 - INJ. #4
5 - INJ. #5
6 - INJ. #6
7 - FUEL INJECTOR RAIL
8 - FUEL DAMPER
9 - PRESSURE TEST PORT CAP
10 - MOUNTING BOLTS (4)
11 - QUICK-CONNECT FITTING
Fig. 22 FUEL INJECTOR RAIL - 4.7L V-8 EN
1 - MOUNTING BOLTS (4)
2 - INJ.#7
3 - INJ.#5
4 - QUICK-CONNECT FITTING
5 - INJ.#3
6 - FUEL INJECTOR RAIL
7 - INJ.#1
8 - CONNECTOR TUBE
9 - INJ.#2
10 - INJ.#4
11 - INJ.#6
12 - INJ.#8
13 - PRESSURE TEST PORT CAP
14 - 16 FUEL DELIVERYWJ
FUEL RAIL (Continued)