oil level JEEP GRAND CHEROKEE 2002 WJ / 2.G Owner's Manual

Component Page
DRIVER SEAT BELT SWITCH........ 8W-80-74
DRIVER SIDE IMPACT SENSOR...... 8W-80-74
EGR SOLENOID (DIESEL)........... 8W-80-74
ELECTRIC BRAKE
(EXCEPT BUILT-UP-EXPORT)...... 8W-80-74
ELECTRONIC SPEED CONTROL
SERVO ......................... 8W-80-74
ENGINE CONTROL MODULE C1
(DIESEL)....................... 8W-80-75
ENGINE CONTROL MODULE C2
(DIESEL)....................... 8W-80-76
ENGINE COOLANT TEMPERATURE
SENSOR (DIESEL)................ 8W-80-77
ENGINE COOLANT TEMPERATURE
SENSOR (GAS)................... 8W-80-77
ENGINE OIL PRESSURE
SENSOR (DIESEL)................ 8W-80-77
ENGINE OIL PRESSURE
SENSOR (GAS)................... 8W-80-78
EVAP/PURGE SOLENOID (GAS)....... 8W-80-78
FRONT POWER OUTLET............ 8W-80-78
FRONT WASHER PUMP............. 8W-80-78
FRONT WIPER MOTOR............. 8W-80-78
FUEL INJECTOR NO. 1 (DIESEL)..... 8W-80-79
FUEL INJECTOR NO. 1 (GAS)........ 8W-80-79
FUEL INJECTOR NO. 2 (DIESEL)..... 8W-80-79
FUEL INJECTOR NO. 2 (GAS)........ 8W-80-79
FUEL INJECTOR NO. 3 (DIESEL)..... 8W-80-79
FUEL INJECTOR NO. 3 (GAS)........ 8W-80-80
FUEL INJECTOR NO. 4 (DIESEL)..... 8W-80-80
FUEL INJECTOR NO. 4 (GAS)........ 8W-80-80
FUEL INJECTOR NO. 5 (DIESEL)..... 8W-80-80
FUEL INJECTOR NO. 5 (GAS)........ 8W-80-81
FUEL INJECTOR NO. 6 (GAS)........ 8W-80-81
FUEL INJECTOR NO. 7 (4.7L)........ 8W-80-81
FUEL INJECTOR NO. 8 (4.7L)........ 8W-80-81
FUEL PRESSURE SENSOR (DIESEL) . . 8W-80-82
FUEL PRESSURE SOLENOID
(DIESEL)....................... 8W-80-82
FUEL PUMP MODULE (GAS)......... 8W-80-82
FUEL TANK MODULE (DIESEL)...... 8W-80-82
GENERATOR (DIESEL).............. 8W-80-82
GENERATOR (GAS)................. 8W-80-83
GLOVE BOX LAMP................. 8W-80-83
HEADLAMP LEVELING SWITCH
(BUILT-UP-EXPORT).............. 8W-80-83
HOOD AJAR SWITCH
(BUILT-UP-EXPORT).............. 8W-80-83
HORN NO. 1....................... 8W-80-83
HORN NO. 2....................... 8W-80-84
HYDRAULIC COOLING MODULE..... 8W-80-84
IDLE AIR CONTROL MOTOR......... 8W-80-84
IGNITION SWITCH C1.............. 8W-80-84
IGNITION SWITCH C2.............. 8W-80-84
INPUT SPEED SENSOR (4.7L)........ 8W-80-85Component Page
INSTRUMENT CLUSTER............ 8W-80-85
INTAKE AIR TEMPERATURE
SENSOR (DIESEL)................ 8W-80-85
INTAKE AIR TEMPERATURE
SENSOR (GAS)................... 8W-80-85
INTAKE PORT SWIRL ACTUATOR
(DIESEL)....................... 8W-80-86
INTRUSION TRANSCEIVER MODULE
(BUILT-UP-EXPORT).............. 8W-80-86
JUNCTION BLOCK BODY
CONTROL MODULE.............. 8W-80-86
JUNCTION BLOCK C1.............. 8W-80-87
JUNCTION BLOCK C2 (LHD)......... 8W-80-88
JUNCTION BLOCK C2 (RHD)......... 8W-80-89
JUNCTION BLOCK C3.............. 8W-80-90
JUNCTION BLOCK C4.............. 8W-80-91
JUNCTION BLOCK C5.............. 8W-80-91
KNOCK SENSOR................... 8W-80-91
LEAK DETECTION PUMP (EXCEPT
BUILT-UP-EXPORT)............... 8W-80-91
LEFT COURTESY LAMP............. 8W-80-91
LEFT DOOR HANDLE COURTESY
LAMP.......................... 8W-80-92
LEFT FOG LAMP................... 8W-80-92
LEFT FRONT DOOR SPEAKER....... 8W-80-92
LEFT FRONT IMPACT SENSOR....... 8W-80-92
LEFT FRONT PARK LAMP........... 8W-80-92
LEFT FRONT PARK/TURN SIGNAL LAMP
(EXCEPT BUILT-UP-EXPORT)...... 8W-80-93
LEFT FRONT SIDE MARKER LAMP
(EXCEPT BUILT-UP-EXPORT)...... 8W-80-93
LEFT FRONT TURN SIGNAL LAMP
(BUILT-UP-EXPORT).............. 8W-80-93
LEFT FRONT WHEEL SPEED
SENSOR........................ 8W-80-93
LEFT HEADLAMP LEVELING MOTOR
(BUILT-UP-EXPORT).............. 8W-80-94
LEFT HIGH BEAM HEADLAMP....... 8W-80-94
LEFT INSTRUMENT PANEL SPEAKER . 8W-80-94
LEFT LIFTGATE AJAR SWITCH....... 8W-80-94
LEFT LOW BEAM HEADLAMP....... 8W-80-94
LEFT MULTI-FUNCTION SWITCH.... 8W-80-95
LEFT REAR DOOR LOCK
MOTOR/AJAR SWITCH............ 8W-80-95
LEFT REAR DOOR SPEAKER......... 8W-80-95
LEFT REAR LAMP ASSEMBLY........ 8W-80-95
LEFT REAR WHEEL SPEED
SENSOR........................ 8W-80-96
LEFT REMOTE RADIO SWITCH...... 8W-80-96
LEFT SIDE REPEATER LAMP
(BUILT-UP-EXPORT).............. 8W-80-96
LEFT VISOR/VANITY LAMP.......... 8W-80-96
LICENSE LAMP NO. 1.............. 8W-80-96
LICENSE LAMP NO. 2.............. 8W-80-97
LIFTGATE FLIP-UP AJAR SWITCH.... 8W-80-97
WJ8W-80 CONNECTOR PIN-OUT 8W - 80 - 3

ENGINE CONTROL MODULE C1 (DIESEL) - BLACK 81 WAY
CAV CIRCUIT FUNCTION
1 Z108 14BK/DG GROUND
2 Z108 14BK/DG GROUND
3 K20 14DB GENERATOR FIELD CONTROL
4 F142 14RD/DG FUSED AUTO SHUT DOWN RELAY OUTPUT
5 F142 14RD/DG FUSED AUTO SHUT DOWN RELAY OUTPUT
6 D52 18DG/WT CAN C BUS(+)
7 D25 20VT/YL PCI BUS
8 K944 20BR/DG CAMSHAFT POSITION SENSOR GROUND
9 K44 20YL/GY CAMSHAFT POSITION SENSOR SIGNAL
10 - -
11 Y53 20BK/YL BOOST PRESSURE SENSOR SIGNAL
12 K155 20YL/WT MASS AIR FLOW SENSOR SIGNAL
13 Y40 20DG/VT FUEL PRESSURE SENSOR SIGNAL
14 K22 20RD/DB ACCELERATOR PEDAL POSITION SENSOR 2 SIGNAL
15 K81 20DB/DG ACCELERATOR PEDAL POSITION SENSOR 1 SIGNAL
16 Y100 20BR/GY FUEL PRESSURE SENSOR GROUND
17 - -
18 - -
19 F300 20RD/BK BATTERY SENSE (+)
20 Z11 20BK/WT BATTERY SENSE (-)
21 K4 18BK/LB SENSOR GROUND
22 F991 20RD/DB FUSED IGNITION SWITCH OUTPUT (RUN-START)
23 K6 18VT/WT SENSOR REFERENCE VOLTAGE B
24 K3 20BK CRANKSHAFT POSITION SENSOR SIGNAL 1
25 D51 18WT CAN C BUS(-)
26 - -
27 - -
28 - -
29 K77 20BR/WT TRANSFER CASE POSITION SENSOR INPUT
30 G60 20BR/DB ENGINE OIL PRESSURE SENSOR SIGNAL
31 - -
32 K25 20VT/DG BATTERY TEMPERATURE SENSOR SIGNAL
33 - -
34 K255 20WT/DG ACCELERATOR PEDAL POSITION SENSOR 1 GROUND
35 Y43 20WT/VT ACCELERATOR PEDAL POSITION SENSOR 1 5-VOLT
SUPPLY
36 C18 20DB A/C PRESSURE SENSOR SIGNAL
37 - -
38 V37 20RD/DG SPEED CONTROL SWITCH SIGNAL
39 K226 20DB/WT FUEL LEVEL SENSOR SIGNAL
40 K2 20DG/RD ENGINE COOLANT TEMPERATURE SENSOR SIGNAL
41 K21 20DG/WT INTAKE AIR TEMPERATURE SENSOR SIGNAL
42 Y101 20 CRANKSHAFT POSITION SENSOR SHIELD
43 K924 20YL CRANKSHAFT POSITION SENSOR SIGNAL 2
44 - -
45 - -
46 - -
47 L50 20WT/DB PRIMARY BRAKE SWITCH SIGNAL
48 K29 20WT/PK SECONDARY BRAKE SWITCH SIGNAL
49 - -
50 F855 18BR/YL SENSOR REFERENCE VOLTAGE A
51 - -
52 - -
53 - -
54 Z189 20BR MASS AIR FLOW SENSOR GROUND
WJ8W-80 CONNECTOR PIN-OUT 8W - 80 - 75

CONNECTOR NAME/
NUMBERCOLOR LOCATION FIG.
Coil On Plug NO. 8 (4.7L) BK Right Side of Engine Near Fuel
Injector No.814, 15
Coil Rail (4.0L) BK Right Rear of Engine 10, 11
Compact Disc Changer BK Near Radio N/S
Compact Disc Changer BK Right Rear Quarter Panel 37
Controller Antilock Brake BK Left Front Engine Compartment 3, 4
Coolant Level Sensor LT GY Right Rear of Engine 5
Crankcase Heater (Diesel) BK Near T/O for G105 8
Crankshaft Position Sensor
(Diesel)BK Rear of Engine Near Transmission
Bell HousingN/S
Crankshaft Position Sensor
(Gas)BK Rear of Engine Near Transmission
Bell Housing10, 11, 14, 15, 17
Data Link Connector BK Under Lower Driver's Side of
Instrument Panel20, 21, 22
Diagnostic Junction Port BK At Steering Column 23
Driver Airbag Squib 1 BK In Steering Wheel N/S
Driver Airbag Squib 2 BK In Steering Wheel N/S
Driver Blend Door Motor/
Actuator (AZC)BK On HVAC Housing N/S
Driver Cylinder Lock Switch GY In Driver Door 24, 25
Driver Door Lock Motor/Ajar
SwitchBK In Driver Door 24, 25
Driver Door Module - C1 WT In Driver Door 24, 25
Driver Door Module - C2 BK In Driver Door N/S
Driver Door Module - C3 BK In Driver Door N/S
Driver Front Door Courtesy
LampBK In Driver Door N/S
Driver Front Power Window
MotorBK In Driver Door 24, 25
Driver Heated Seat Back
(Premium I/III)GN At Driver Seat N/S
Driver Heated Seat Cushion
(Premium I/III)BK At Driver Seat N/S
Driver Heated Seat Switch WT Center of Instrument Panel 19 20, 21
Driver Lumbar Motor
(Midline/Premium)BK At Driver Seat N/S
Driver Lumbar Switch
(Midline/Premium)WT At Driver Seat N/S
Driver Power Mirror BK At Driver Door N/S
Driver Power Seat Front Riser
MotorRD At Driver Seat N/S
Driver Power Seat Front Riser
Motor Sensor (Premium II/III)BK At Driver Seat N/S
Driver Power Seat Horizontal
MotorBK At Driver Seat N/S
8W - 91 - 4 8W-91 CONNECTOR/GROUND/SPLICE LOCATIONWJ
CONNECTOR/GROUND/SPLICE LOCATION (Continued)

CONNECTOR NAME/
NUMBERCOLOR LOCATION FIG.
Fuel Pump Module (Gas) BK Near Fuel Tank 33, 35
Fuel Tank Module Diesel) BK Near Fuel Tank 33, 35
Generator (Diesel) LTGY At Generator 8
Generator (Gas) BK At Generator N/S
Glove Box Lamp BK Inside Glove Box 19, 20, 22
Headlamp Leveling Switch
(Built-Up-Export)WT Driver Side of Instrument Panel 20
Hood Ajar Switch BK Left Side of Engine Compartment 3, 4
Horn No.1 BK Right Front Fascia 5
Horn No.2 BK Right Front Fascia 5
Hydraulic Cooling Module BK Right Front of Engine Compartment 5
Idle Air Control Motor BK Left Side of Engine Near Throttle
Body13
Ignition Switch - C1 WT On Steering Column 23
Ignition Switch - C2 BK On Steering Column 23
Input Speed Sensor (4.7L) BK Left Side of Transmission 16
Instrument Cluster WT At Instrument Cluster 19, 20
Intake Air Temperature Sensor
(Gas)GY Left Side of Engine 9, 13
Intake Air Temperature Sensor
(Diesel)BK Near T/O for Crankcase Heater 8
Intake Port Swirl Actuator
(Diesel)BK Right Rear of Engine Compartment N/S
Intrusion Transceiver Module
(Built-up-Export)BK In The Overhead N/S
Junction Block - C1 BK At Junction Block 30, 31, 33
Junction Block - C2 BK At Junction Block 30, 31
Junction Block - C3 BK At Junction Block 21, 22, 30
Junction Block - C4 WT At Junction Block 30, 31
Junction Block - C5 WT At Junction Block 30, 31
Knock Sensor (4.7L High
Output)BK Right Rear Side of Engine, Near
Coil on Plug No.8N/S
Leak Detection Pump (Except
Built-Up-Export)Left Front Wheel Opening 3
Left Courtesy Lamp BK Left Side of Instrument Panel 21 22, 23
Left Curtain Airbag BK Near Left C Pillar 37
Left Door Handle Courtesy
LampBK At Lamp N/S
Left Fog Lamp BK At Lamp 3, 4
Left Front Door Speaker WT In Left Front Door 24, 27
Left Front Impact Sensor BK Left Front Frame Near Windshield
Washer Pump3, 4
Left Front Park Lamp WT At Lamp N/S
8W - 91 - 6 8W-91 CONNECTOR/GROUND/SPLICE LOCATIONWJ
CONNECTOR/GROUND/SPLICE LOCATION (Continued)

DIAGNOSIS AND TESTINGÐ ENGINE DIAGNOSIS - MECHANICAL
ENGINE MECHANICAL DIAGNOSIS CHART
CONDITION POSSIBLE CAUSES CORRECTION
NOISY VALVES/LIFTERS 1. High or low oil level in crankcase 1. Check for correct oil level. Adjust
oil level by draining or adding as
needed
2. Thin or diluted oil 2. Change oil. (Refer to 9 -
ENGINE/LUBRICATION/OIL -
STANDARD PROCEDURE)
3. Low oil pressure 3. Check engine oil level. If ok,
Perform oil pressure test. (Refer to 9
- ENGINE/LUBRICATION -
DIAGNOSIS AND TESTING) for
engine oil pressure test/specifications
4. Dirt in tappets/lash adjusters 4. Clean/replace hydraulic tappets/
lash adjusters
5. Bent push rod(s) 5. Install new push rods
6. Worn rocker arms 6. Inspect oil supply to rocker arms
and replace worn arms as needed
7. Worn tappets/lash adjusters 7. Install new hydraulic tappets/lash
adjusters
8. Worn valve guides 8. Inspect all valve guides and
replace as necessary
9. Excessive runout of valve seats or
valve faces9. Grind valves and seats
CONNECTING ROD NOISE 1. Insufficient oil supply 1. Check engine oil level.
2. Low oil pressure 2. Check engine oil level. If ok,
Perform oil pressure test. (Refer to 9
- ENGINE/LUBRICATION -
DIAGNOSIS AND TESTING) engine
oil pressure test/specifications
3. Thin or diluted oil 3. Change oil to correct viscosity.
(Refer to 9 - ENGINE/LUBRICATION/
OIL - STANDARD PROCEDURE) for
correct procedure/engine oil
specifications
4. Excessive connecting rod bearing
clearanceMeasure bearings for correct
clearance with plasti-gage. Repair as
necessary
5. Connecting rod journal out of
round5. Replace crankshaft or grind
journals
6. Misaligned connecting rods 6. Replace bent connecting rods
MAIN BEARING NOISE 1. Insufficient oil supply 1. Check engine oil level.
2. Low oil pressure 2. Check engine oil level. If ok,
Perform oil pressure test. (Refer to 9
- ENGINE/LUBRICATION -
DIAGNOSIS AND TESTING)
9 - 6 ENGINE - 4.0LWJ
ENGINE - 4.0L (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
3. Thin or diluted oil 3. Change oil to correct viscosity.
4. Excessive main bearing clearance 4. Measure bearings for correct
clearance. Repair as necessary
5. Excessive end play 5. Check crankshaft thrust bearing for
excessive wear on flanges
6. Crankshaft main journal out of
round or worn6. Grind journals or replace
crankshaft
7. Loose flywheel or torque converter 7. Inspect crankshaft, flexplate/
flywheel and bolts for damage.
Tighten to correct torque
LOW OIL PRESSURE 1. Low oil level 1. Check oil level and fill if necessary
2. Faulty oil pressure sending unit 2. Install new sending unit
3. Clogged oil filter 3. Install new oil filter
4. Worn oil pump 4. Replace oil pump assembly.
5. Thin or diluted oil 5. Change oil to correct viscosity.
6. Excessive bearing clearance 6. Measure bearings for correct
clearance
7. Oil pump relief valve stuck 7. Remove valve to inspect, clean
and reinstall
8. Oil pump suction tube loose,
broken, bent or clogged8. Inspect suction tube and clean or
replace if necessary
9. Oil pump cover warped or cracked 9. Install new oil pump
OIL LEAKS 1. Misaligned or deteriorated gaskets 1. Replace gasket
2. Loose fastener, broken or porous
metal part2. Tighten, repair or replace the part
3. Front or rear crankshaft oil seal
leaking3. Replace seal
4. Leaking oil gallery plug or cup
plug4. Remove and reseal threaded plug.
Replace cup style plug
EXCESSIVE OIL
CONSUMPTION OR SPARK
PLUGS OIL FOULED1. CCV System malfunction 1. (Refer to 25 - EMISSIONS
CONTROL/EVAPORATIVE
EMISSIONS - DESCRIPTION) for
correct operation
2. Defective valve stem seal(s) 2. Repair or replace seal(s)
3. Worn or broken piston rings 3. Hone cylinder bores. Install new
rings
4. Scuffed pistons/cylinder walls 4. Hone cylinder bores and replace
pistons as required
5. Carbon in oil control ring groove 5. Remove rings and de-carbon
piston
6. Worn valve guides 6. Inspect/replace valve guides as
necessary
7. Piston rings fitted too tightly in
grooves7. Remove rings and check ring end
gap and side clearance. Replace if
necessary
WJENGINE - 4.0L 9 - 7
ENGINE - 4.0L (Continued)

DIAGNOSIS AND TESTINGÐCYLINDER
COMPRESSION PRESSURE
The results of a cylinder compression pressure test
can be utilized to diagnose several engine malfunc-
tions.
Ensure the battery is completely charged and the
engine starter motor is in good operating condition.
Otherwise, the indicated compression pressures may
not be valid for diagnosis purposes.
(1) Clean the spark plug recesses with compressed
air.
(2) Remove the spark plugs (Refer to 8 - ELEC-
TRICAL/IGNITION CONTROL/SPARK PLUG -
REMOVAL).
(3) Secure the throttle in the wide-open position.
(4) Disconnect the ignition coil.
(5) Insert a compression pressure gauge and rotate
the engine with the engine starter motor for three
revolutions.
(6) Record the compression pressure on the third
revolution. Continue the test for the remaining cylin-
ders.
(Refer to 9 - ENGINE - SPECIFICATIONS) for the
correct engine compression pressures.
DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE
The combustion pressure leakage test provides an
accurate means for determining engine condition.
Combustion pressure leakage testing will detect:
²Exhaust and intake valve leaks (improper seat-
ing)
²Leaks between adjacent cylinders or into water
jacket²Any causes for combustion/compression pressure
loss
WARNING: DO NOT REMOVE THE RADIATOR CAP
WITH THE SYSTEM HOT AND UNDER PRESSURE.
SERIOUS BURNS FROM HOT COOLANT CAN
OCCUR.
Check the coolant level and fill as required. DO
NOT install the radiator cap.
Start and operate the engine until it attains nor-
mal operating temperature, then turn OFF the
engine.
Remove the spark plugs.
Remove the oil filler cap.
Remove the air cleaner.
Calibrate the tester according to the manufactur-
er's instructions. The shop air source for testing
should maintain 483 kPa (70 psi) minimum, 1,379
kPa (200 psi) maximum and 552 kPa (80 psi) recom-
mended.
Perform the test procedure on each cylinder accord-
ing to the tester manufacturer's instructions. While
testing, listen for pressurized air escaping through
the throttle body, tailpipe or oil filler cap opening.
Check for bubbles in the radiator coolant.
All gauge pressure indications should be equal,
with no more than 25% leakage.
FOR EXAMPLE:At 552 kPa (80 psi) input pres-
sure, a minimum of 414 kPa (60 psi) should be main-
tained in the cylinder CYLINDER COMBUSTION
PRESSURE LEAKAGE DIAGNOSIS CHART .
CYLINDER COMBUSTION PRESSURE LEAKAGE DIAGNOSIS CHART
CONDITION POSSIBLE CAUSE CORRECTION
AIR ESCAPES THROUGH
THROTTLE BODYIntake valve bent, burnt, or not
seated properlyInspect valve and valve seat.
Reface or replace, as necessary
AIR ESCAPES THROUGH
TAILPIPEExhaust valve bent, burnt, or not
seated properlyInspect valve and valve seat.
Reface or replace, as necessary
AIR ESCAPES THROUGH
RADIATORHead gasket leaking or cracked
cylinder head or blockRemove cylinder head and inspect.
Replace defective part
MORE THAN 50% LEAKAGE
FROM ADJACENT CYLINDERSHead gasket leaking or crack in
cylinder head or block between
adjacent cylindersRemove cylinder head and inspect.
Replace gasket, head, or block as
necessary
MORE THAN 25% LEAKAGE AND
AIR ESCAPES THROUGH OIL
FILLER CAP OPENING ONLYStuck or broken piston rings;
cracked piston; worn rings and/or
cylinder wallInspect for broken rings or piston.
Measure ring gap and cylinder
diameter, taper and out-of-round.
Replace defective part as necessary
9 - 8 ENGINE - 4.0LWJ
ENGINE - 4.0L (Continued)

(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)

ENGINE BLOCK
CLEANING
Thoroughly clean the oil pan and engine block gas-
ket surfaces.
Use compressed air to clean out:
²The galley at the oil filter adaptor hole.
²The front and rear oil galley holes.
²The feed holes for the crankshaft main bearings.
Once the block has been completely cleaned, apply
Loctite PST pipe sealant with Teflon 592 to the
threads of the front and rear oil galley plugs. Tighten
the plugs to 34 N´m (25 ft. lbs.) torque.
INSPECTION
(1) It is mandatory to use a dial bore gauge to
measure each cylinder bore diameter (Fig. 29). To
correctly select the proper size piston, a cylinder bore
gauge, capable of reading in 0.003 mm (.0001 in.)
INCREMENTS is required. If a bore gauge is not
available, do not use an inside micrometer.
(2) Measure the inside diameter of the cylinder
bore at three levels below top of bore. Start perpen-
dicular (across or at 90 degrees) to the axis of the
crankshaft and then take two additional reading.(3) Measure the cylinder bore diameter crosswise
to the cylinder block near the top of the bore. Repeat
the measurement near the middle of the bore, then
repeat the measurement near the bottom of the bore.
(4) Determine taper by subtracting the smaller
diameter from the larger diameter.
(5) Rotate measuring device 90É and repeat steps
above.
(6) Determine out-of-roundness by comparing the
difference between each measurement.
(7) If cylinder bore taper does not exceed 0.025
mm (0.001 inch) and out-of-roundness does not
exceed 0.025 mm (0.001 inch), the cylinder bore can
be honed. If the cylinder bore taper or out- of-round
condition exceeds these maximum limits, the cylinder
must be bored and then honed to accept an oversize
piston. A slight amount of taper always exists in the
cylinder bore after the engine has been in use for a
period of time.
CAMSHAFT & BEARINGS
DESCRIPTION
The camshaft is made of gray cast iron with twelve
machined lobes and four bearing journals (Fig. 30).
When the camshaft rotates the lobes actuate the tap-
pets and push rods, forcing upward on the rocker
arms which applies downward force on the valves.
Fig. 28 Valve and Valve
1 - VALVE LOCKS (3±BEAD)
2 - RETAINER
3 - VALVE STEM OIL SEAL
4 - INTAKE VALVE
5 - EXHAUST VALVE
6 - VALVE SPRINGFig. 29 Cylinder Bore Measurement
9 - 30 ENGINE - 4.0LWJ
VALVE SPRINGS (Continued)

(e) If end play is not within specification, inspect
crankshaft thrust faces for wear. If no wear is
apparent, replace the thrust bearing and measure
end play. If end play is still not within specifica-
tion, replace the crankshaft.
(11) If the crankshaft was removed, install the
crankshaft into the cylinder block.
(12) Install main bearing cap brace tighten nuts to
47 N´m (35 ft. lbs.) torque.
(13) Install oil pump assy. and tighten attaching
bolts to 23 N´m (17 ft. lbs.)
(14) Install the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - INSTALLATION).
(15) Install the drain plug. Tighten the plug to 34
N´m (25 ft. lbs.) torque.
(16) Lower the vehicle.
(17) Install the spark plugs. Tighten the plugs to
37 N´m (27 ft. lbs.) torque.
(18) Fill the oil pan with engine oil to the full
mark on the dipstick level.
(19) Connect negative cable to battery.
CRANKSHAFT OIL SEAL -
FRONT
REMOVAL
This procedure is done with the timing case cover
installed.
(1) Disconnect negative cable from battery.
(2) Remove the serpentine drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).(3) Remove the vibration damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
REMOVAL).
(4) Remove the radiator shroud.
(5) Carefully remove the oil seal. Make sure seal
bore is clean.
INSTALLATION
This procedure is done with the timing case cover
installed.
(1) Position the replacement oil seal on Timing
Case Cover Alignment and Seal Installation Tool
6139 with seal open end facing inward. Apply a light
film of Perfect Seal, or equivalent, on the outside
diameter of the seal. Lightly coat the crankshaft with
engine oil.
(2) Position the tool and seal over the end of the
crankshaft and insert a draw screw tool into Seal
Installation Tool 6139 (Fig. 50). Tighten the nut
against the tool until it contacts the cover.
(3) Remove the tools. Apply a light film of engine
oil on the vibration damper hub contact surface of
the seal.
(4) Apply MopartSilicone Rubber Adhesive Seal-
ant to the keyway in the crankshaft and insert the
key. With the key inserted in the keyway in the
crankshaft, install the vibration damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
INSTALLATION).
(5) Install the serpentine belt (Refer to 7 - COOL-
ING/ACCESSORY DRIVE/DRIVE BELTS - INSTAL-
LATION).
(6) Install the radiator shroud.
(7) Connect negative cable to battery.
Fig. 49 Crankshaft End Play Measurement
1 - DIAL INDICATOR
2 - CRANKSHAFT
Fig. 50 Timing Case Cover Oil Seal Installation
1 - SEAL INSTALLATION TOOL
2 - DRAW SCREW TOOL
WJENGINE - 4.0L 9 - 41
CRANKSHAFT MAIN BEARINGS (Continued)