2002 JEEP GRAND CHEROKEE 4.7l v8 ac system

OPERATION - 3/8º PRESSURE HOSE
High pressure power steering fluid is transmitted
from the hydraulic fan motor to the steering gear by
the 3/8º steering line.
OPERATION - 3/8º GEAR OUTLET HOSE
The gear outlet hose transmits power steering fluid
under moderate low pressure to the power steering
cooler inlet tube.
OPERATION - 3/8ºRETURN HOSE
Low pressure power steering fluid is transmitted
from the steering cooler back to the power steering
pump by the 3/8º return hose.
REMOVAL
REMOVAL - 1/2(PRESSURE HOSE
(1)Drain the power steering fluid from the reservoir.
(2) Remove the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
REMOVAL).
(3) Raise and support the vehicle.
(4) Remove the metal skid plate.
(5) Disconnect the high pressure hose from the
hydraulic fan motor (Fig. 8).
(6) Disconnect the high pressure hose from the
power steering pump (Fig. 8).
(7) Remove the hose from the clipped position on
the fan shroud.
(8) Remove the hose from the vehicle.
REMOVAL - 1/2(RETURN HOSE
(1) Drain the power steering fluid from the reser-
voir.
(2) Remove the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
REMOVAL).
(3) Raise and support the vehicle.
(4) Remove the metal skid plate.
(5) Disconnect the rubber return hose from the
hydraulic fan motor (Fig. 9).
(6) Disconnect the rubber return hose from the
power steering reservoir .
(7) Remove the hose from the vehicle.
REMOVAL - 3/8(PRESSURE HOSE
(1) Drain the power steering fluid from the reser-
voir.
(2) Remove the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
REMOVAL).
(3) Raise and support the vehicle.
(4) Remove the metal skid plate.
(5) Disconnect the high pressure hose from the
hydraulic fan motor (Fig. 10).
(6) Disconnect the high pressure hose from the
power steering gear (Fig. 10).
(7) Remove the hose from the clipped position on
the fan shroud.
(8) Remove the hose from the vehicle.
REMOVAL - 3/8(RETURN HOSE
(1) Drain the power steering fluid from the reser-
voir.
(2) Remove the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
REMOVAL).
(3) Raise and support the vehicle.
(4) Disconnect the rubber hose from the steering
cooler outlet tube (Fig. 12).
Fig. 11 3/8(GEAR OUTLET HOSE
1 - HOSE CLAMP
2 - 3/89GEARR OUTLET HOSE
Fig. 12 3/8(RETURN HOSE
1 - HOSE CLAMP
2 - 3/89RETURN HOSE
3 - HYDRAULIC COOLING FAN MOTOR
WJPUMP 19 - 39
HOSES - 4.7L (Continued)

(5) Disconnect the rubber hose from the power
steering reservoir (Fig. 12).
(6) Remove the hose from the vehicle.
REMOVAL - 3/8(GEAR OUTLET HOSE
(1) Drain the power steering fluid from the reser-
voir.
(2) Remove the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
REMOVAL).
(3) Raise and support the vehicle.
(4) Disconnect the rubber hose from the steering
cooler inlet tube (Fig. 11).
(5) Disconnect the metal tube from the power
steering gear (Fig. 11).
(6) Remove the hose from the vehicle.
REMOVAL - INLET COOLER HOSE
(1) Disconnect negative battery cable at battery.
(2) Drain the power steering fluid out of the reser-
voir.
(3) Remove the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
REMOVAL).
(4) Remove the front fascia grille assembly,(Refer
to 13 - FRAMES & BUMPERS/BUMPERS/FRONT
FASCIA - REMOVAL).
(5) Remove the grille opening reinforcement panel
(6) Place a drain pan under the cooler.
(7) Disconnect the lower hose at cooler (Fig. 6).
(8) Disconnect the cooler hose at the gear.
(9) Remove the bracket holding the cooler hoses
(Fig. 13).
(10) Remove the cooler hose from the vehicle.
REMOVAL - OUTLET COOLER HOSE
(1) Disconnect negative battery cable at battery.
(2) Drain the power steering fluid out of the reser-
voir.
(3) Remove the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
REMOVAL).
(4) Remove the front fascia grille assembly,(Refer
to 13 - FRAMES & BUMPERS/BUMPERS/FRONT
FASCIA - REMOVAL).
(5) Remove the grille opening reinforcement panel
(6) Place a drain pan under the cooler.
(7) Disconnect the upper hose at cooler (Fig. 6).
(8) Disconnect the cooler hose at the reservoir.
(9) Remove the bracket holding the cooler hoses
(Fig. 13).
(10) Remove the cooler hose from the vehicle.
INSTALLATION
INSTALLATION - 1/2(PRESSURE HOSE
NOTE: Lubrication and a new o-ring must be used
when reinstalling.
(1) Install the hoses to the vehicle.
(2) Reconnect the high pressure hose to the power
steering pump (Fig. 8) Tighten the hose to 22.5 N´m
(17 ft.lbs.).
(3) Reconnect the high pressure hose to the
hydraulic fan motor (Fig. 8) Tighten the hose to 22.5
N´m (17 ft.lbs.).
(4) Install the hose to the clipped position on the
fan shroud.
(5) Install the metal skid plate.
(6) Install the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
INSTALLATION).
(7) Refill the power steering fluid and bleed the
system,(Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE).
INSTALLATION - 1/2(RETURN HOSE
(1) Install the hoses to the vehicle.
(2) Reconnect the rubber return hose to the power
steering reservoir (Fig. 9) Tighten the hose clamp.
(3) Reconnect the rubber return hose to the
hydraulic fan motor (Fig. 9) Tighten the hose.
(4) Install the metal skid plate.
(5) Install the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
INSTALLATION).
(6) Refill the power steering fluid and bleed the
system,(Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE).
Fig. 13 COOLER HOSES MOUNTING BRACKET
1 - RADIATOR
2 - COOLER HOSES MOUNTING BRACKET
2 - COOLER HOSE
19 - 40 PUMPWJ
HOSES - 4.7L (Continued)

INSTALLATION - 3/8(PRESSURE HOSE
NOTE: Lubrication and a new o-ring must be used
when reinstalling.
(1) Install the hoses to the vehicle.
(2) Reconnect the high pressure hose to the
hydraulic fan motor (Fig. 10) Tighten the hose to
22.5 N´m (17 ft.lbs.).
(3) Reconnect the high pressure hose to the power
steering gear (Fig. 10) Tighten the hose to 22.5 N´m
(17 ft.lbs.).
(4) Install the hose to the clipped position on the
fan shroud.
(5) Install the metal skid plate.
(6) Install the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
INSTALLATION).
(7) Refill the power steering fluid and bleed the
system,(Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE).
INSTALLATION - 3/8(RETURN HOSE
(1) Install the hoses to the vehicle.
(2) Reconnect the rubber hose to the steering
cooler outlet tube (Fig. 12) Tighten the hose clamp.
(3) Reconnect the rubber hose to the power steer-
ing reservoir (Fig. 12) Tighten the hose clamp.
(4) Install the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
INSTALLATION).
(5) Refill the power steering fluid and bleed the
system,(Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE).
INSTALLATION - 3/8(GEAR OUTLET HOSE
NOTE: Lubrication and a new o-ring must be used
when reinstalling.
(1) Install the hoses to the vehicle.
(2) Reconnect the rubber hose to the steering
cooler inlet tube (Fig. 11) Tighten the hose clamp.
(3)
Reconnect the metal tube to the power steering
gear (Fig. 11) Tighten the hose to 22.5 N´m (17 ft.lbs.).
(4) Install the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
INSTALLATION).
(5) Refill the power steering fluid and bleed the
system,(Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE).
INSTALLATION - INLET COOLER HOSE
(1) Install the cooler hose to the vehicle.
(2) Reconnect the cooler hose at the gear.
(3) Reconnect the lower hose at cooler (Fig. 6).
Tighten the hose to 22.5 N´m (17 ft.lbs.)
(4) Install the bracket holding the cooler hoses
(Fig. 13).(5) Install the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
INSTALLATION).
(6) Install the grille opening reinforcement panel
(7) Install the front fascia grille assembly, (Refer to
13 - FRAMES & BUMPERS/BUMPERS/FRONT
FASCIA - INSTALLATION).
(8) Reconnect negative battery cable at battery.
(9) Refill the power steering fluid and bleed the
system,(Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE).
INSTALLATION - OUTLET COOLER HOSE
(1) Install the cooler hose to the vehicle.
(2) Reconnect the cooler hose at the reservoir.
(3) Reconnect the upper hose at the cooler (Fig. 6).
Tighten the hose to 22.5 N´m (17 ft. lbs.)
(4) Install the bracket holding the cooler hoses
(Fig. 13). Tighten the bracket to 22.5 N´m (17 ft. lbs.)
(5) Install the air box,(Refer to 9 - ENGINE/AIR
INTAKE SYSTEM/AIR CLEANER HOUSING -
INSTALLATION).
(6) Install the grille opening reinforcement panel
(7) Install the front fascia grille assembly, (Refer to
13 - FRAMES & BUMPERS/BUMPERS/FRONT
FASCIA - INSTALLATION).
(8) Reconnect negative battery cable at battery.
(9) Refill the power steering fluid and bleed the
system,(Refer to 19 - STEERING/PUMP - STAN-
DARD PROCEDURE).
PULLEY
DESCRIPTION
POWER STEERING PUMP PULLEY - 3.1L
DIESEL
To service the power steering pump pulley on the
3.1L turbo diesel engine. Refer to the power steering
pump removal and installation procedure in this
group. The pulley must be removed to service the
pump assembly. Detailed instructions are provided in
the pump procedure.
REMOVAL
CAUTION: On vehicles equipped with the 4.0L or
4.7L, Do not reuse the old power steering pump
pulley it is not intended for reuse. A new pulley
must be installed if removed.
(1) Remove pump assembly.
(2) Remove pulley from pump with Puller C-4333
or equivalent puller (Fig. 14).
WJPUMP 19 - 41
HOSES - 4.7L (Continued)

INSTALLATION
INSTALLATION
WARNING: REVIEW THE WARNINGS AND CAU-
TIONS IN THE FRONT OF THIS SECTION BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - WARNING) (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING - CAUTION)
Any kinks or sharp bends in the refrigerant plumb-
ing will reduce the capacity of the entire air condi-
tioning system. Kinks and sharp bends reduce the
flow of refrigerant in the system. A good rule for the
flexible hose refrigerant lines is to keep the radius of
all bends at least ten times the diameter of the hose.
In addition, the flexible hose refrigerant lines should
be routed so they are at least 80 millimeters (3
inches) from the exhaust manifold.
High pressures are produced in the refrigerant sys-
tem when the air conditioning compressor is operat-
ing. Extreme care must be exercised to make sure
that each of the refrigerant system connections is
pressure-tight and leak free. It is a good practice to
inspect all flexible hose refrigerant lines at least once
a year to make sure they are in good condition and
properly routed.
NOTE: If a replacement compressor is being
installed, be certain to check the refrigerant oil
level. (Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING/REFRIGERANT OIL - STANDARD PRO-
CEDURE) Use only refrigerant oil of the type
recommended for the compressor in the vehicle.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING/REFRIGERANT OIL - DESCRIPTION)
(1) Install the compressor. Tighten the 4.0L
mounting bolts fastening the compressor to the block
to 45-65 N´m (35-50 ft. lbs.). Tighten the mounting
bolts holding the rear brace to the compressor and
block to 40-55 N´m (30-40 ft. lbs.). Tighten the 4.7L
compressor front mounting screws to 45-65 N´m
(35-50 ft. lbs.), and the rear mounting screws to
35-45 N´m (25-35 ft. lbs.).
(2) Remove the tape or plugs from all of the
opened refrigerant line fittings. Install the suction
line and discharge line fittings to the manifold on the
compressor. Tighten the mounting bolts to 25.4 N´m
(225 in. lbs.).
(3) Install the serpentine drive belt. Refer to Cool-
ing for the procedures.
(4) Plug in the compressor clutch coil wire harness
connector.
(5) Connect the battery negative cable.(6) Evacuate the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM EVACUATE)
(7) Charge the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM CHARGE)
INSTALLATION - 2.7L TURBO DIESEL
CAUTION: Check the oil level before installing the
new compressor. (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING/REFRIGERANT OIL -
STANDARD PROCEDURE)
WARNING: REVIEW THE WARNINGS AND CAU-
TIONS IN THE FRONT OF THIS SECTION BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - WARNING) (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING - CAUTION)
Any kinks or sharp bends in the refrigerant plumb-
ing will reduce the capacity of the entire air condi-
tioning system. Kinks and sharp bends reduce the
flow of refrigerant in the system. A good rule for the
flexible hose refrigerant lines is to keep the radius of
all bends at least ten times the diameter of the hose.
In addition, the flexible hose refrigerant lines should
be routed so they are at least 80 millimeters (3
inches) from the exhaust manifold.
High pressures are produced in the refrigerant sys-
tem when the air conditioning compressor is operat-
ing. Extreme care must be exercised to make sure
that each of the refrigerant system connections is
pressure-tight and leak free. It is a good practice to
inspect all flexible hose refrigerant lines at least once
a year to make sure they are in good condition and
properly routed.
(1) Lift the compressor into position and install
the (4) mounting bolts. Torque the bolts to 41 N´m
(30 ft. lbs.).
(2) Connect the compressor clutch electrical con-
nector.
(3) Install both refrigerant lines on the compressor.
Make certain the sealing 0-rings are free of tears and
well lubricated with R-134a refrigerant oil. Torque
the line retaining bolts to 22 N´m (200 in. lbs.).
(4) Install the front splash shield (if equipped).
(5) Lower the vehicle from the hoist.
(6) Install the accessory drive belt on the compres-
sor clutch. Refer to Cooling for the procedure.
(7) Evacuate the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
WJPLUMBING 24 - 61
A/C COMPRESSOR (Continued)

EVAPORATIVE EMISSIONS
TABLE OF CONTENTS
page page
EVAPORATIVE EMISSIONS
DESCRIPTION
DESCRIPTION - EVAPORATION CONTROL
SYSTEM............................24
DESCRIPTION - CCV SYSTEM...........25
DESCRIPTION - PCV SYSTEM...........25
OPERATION
OPERATION - 4.0L CCV SYSTEM.........26
OPERATION - 4.7L PCV SYSTEM.........26
SPECIFICATIONS
TORQUE - EVAPORATION SYSTEM.......27
CCV HOSE
DIAGNOSIS AND TESTING - CCV SYSTEM -
4.0L................................28
REMOVAL - FIXED ORIFICE FITTING........28
INSTALLATION - FIXED ORIFICE FITTING....29
EVAP/PURGE SOLENOID
DESCRIPTION.........................29
OPERATION...........................29
REMOVAL.............................29
INSTALLATION.........................29
FUEL FILLER CAP
DESCRIPTION.........................29
OPERATION...........................29REMOVAL.............................29
LEAK DETECTION PUMP
DESCRIPTION.........................30
OPERATION...........................31
DIAGNOSIS AND TESTING - ENABLING
CONDITIONS TO RUN EVAP LEAK
DETECTION TEST.....................32
REMOVAL.............................35
INSTALLATION.........................35
ORVR
DESCRIPTION.........................37
OPERATION...........................37
P C V VA LV E
DIAGNOSIS AND TESTING - PCV VALVE/PCV
SYSTEM - 4.7L.......................37
REMOVAL - PCV VALVE - 4.7L.............39
INSTALLATION - PCV VALVE - 4.7L.........39
VACUUM LINES
DESCRIPTION.........................39
VAPOR CANISTER
DESCRIPTION.........................39
OPERATION...........................39
REMOVAL.............................40
INSTALLATION.........................40
EVAPORATIVE EMISSIONS
DESCRIPTION
DESCRIPTION - EVAPORATION CONTROL
SYSTEM
The evaporation control system prevents the emis-
sion of fuel tank vapors into the atmosphere. When
fuel evaporates in the fuel tank, the vapors pass
through the control valve, through the fuel manage-
ment valve, and through vent hoses and tubes to a
charcoal filled evaporative canister. The canister tem-
porarily holds the vapors. The Powertrain Control
Module (PCM) allows intake manifold vacuum todraw vapors into the combustion chambers during
certain operating conditions.
Gas powered engines use a duty cycle purge sys-
tem. The PCM controls vapor flow by operating the
duty cycle EVAP purge solenoid. Refer to Duty Cycle
EVAP Canister Purge Solenoid.
When equipped with certain emissions packages, a
Leak Detection Pump (LDP) will be used as part of
the evaporative system for OBD II requirements.
Also refer to Leak Detection Pump.
Vehicles powered with gasoline engines are also
equipped with ORVR (On-Board Refueling Vapor
Recovery). Refer to ORVR for additional information.
25 - 24 EVAPORATIVE EMISSIONSWJ

NOTE: The evaporative system uses specially man-
ufactured lines/hoses. If replacement becomes nec-
essary, only use fuel resistant, low permeation
hose.
Certain components can be found in (Fig. 1).
DESCRIPTION - CCV SYSTEM
The 4.0L 6±cylinder engine is equipped with a
Crankcase Ventilation (CCV) system. The system
consists of:
²A fixed orifice fitting of a calibrated size. This
fitting is pressed into a rubber grommet located on
the top/rear of cylinder head (valve) cover (Fig. 2).
²a pair of breather tubes (lines) to connect the
system components.
²the air cleaner housing.
²an air inlet fitting (Fig. 2).
DESCRIPTION - PCV SYSTEM
The 4.7L V-8 engine is equipped with a closed
crankcase ventilation system and a Positive Crank-
case Ventilation (PCV) valve.
This system consists of:
Fig. 1 ORVR / LDP COMPONENTS
1 - FUEL TANK (LEFT SIDE) 6 - EVAP CANISTER
2 - FRAME RAIL (LEFT-REAR OUTSIDE) 7 - LDP FILTER
3 - FUEL VENT TUBE 8 - TWO-PIECE SUPPORT BRACKET
4 - FUEL FILL TUBE 9 - LEAK DETECTION PUMP (LDP)
5 - CONTROL VALVE
Fig. 2 CCV SystemÐ4.0L Engine
1 - AIR INLET FITTING
2 - FIXED ORIFICE FITTING
3 - CCV BREATHER TUBE (REAR)
4 - INT. MAN. FITTING
5 - CCV BREATHER TUBE (FRONT)
WJEVAPORATIVE EMISSIONS 25 - 25
EVAPORATIVE EMISSIONS (Continued)

²a PCV valve mounted to the oil filler housing
(Fig. 3). The PCV valve is sealed to the oil filler
housing with an o-ring.
²the air cleaner housing
²two interconnected breathers threaded into the
rear of each cylinder head (Fig. 4).
²tubes and hose to connect the system compo-
nents.
OPERATION
OPERATION - 4.0L CCV SYSTEM
The CCV system performs the same function as a
conventional PCV system, but does not use a vacuum
controlled PCV valve.
The fixed orifice fitting meters the amount of
crankcase vapors drawn out of the engine.
When the engine is operating, fresh air enters the
engine and mixes with crankcase vapors. Engine vac-uum draws the vapor/air mixture through the fixed
orifice and into the intake manifold. The vapors are
then consumed during engine combustion.
OPERATION - 4.7L PCV SYSTEM
The PCV system operates by engine intake mani-
fold vacuum. Filtered air is routed into the crankcase
through the air cleaner hose and crankcase breath-
ers. The metered air, along with crankcase vapors,
are drawn through the PCV valve and into a passage
in the intake manifold. The PCV system manages
crankcase pressure and meters blow-by gases to the
intake system, reducing engine sludge formation.
The PCV valve contains a spring loaded plunger.
This plunger meters the amount of crankcase vapors
routed into the combustion chamber based on intake
manifold vacuum.
TYPICALPCV valves are shown in (Fig. 5), (Fig.
6) and (Fig. 7).
When the engine is not operating, or during an
engine pop-back, the spring forces the plunger back
against the seat (Fig. 5). This will prevent vapors
from flowing through the valve.
Fig. 3 PCV Valve/Oil Filler Tube (Housing)Ð4.7L
Engine
1 - O-RING
2 - LOCATING TABS
3 - CAM LOCK
4 - OIL FILLER TUBE
5 - PCV LINE/HOSE
6 - P C V VA LV E
Fig. 4 PCV System Hoses/TubesÐ4.7L Engine
1 - FRESH AIR FITTING
2 - CONNECTING TUBES/HOSES
3 - CRANKCASE BREATHERS (2)
4 - RUBBER HOSE
5 - AIR CLEANER RESONATOR
25 - 26 EVAPORATIVE EMISSIONSWJ
EVAPORATIVE EMISSIONS (Continued)

During periods of high manifold vacuum, such as
idle or cruising speeds, vacuum is sufficient to com-
pletely compress spring. It will then pull the plunger
to the top of the valve (Fig. 6). In this position there
is minimal vapor flow through the valve.
During periods of moderate manifold vacuum, the
plunger is only pulled part way back from inlet. This
results in maximum vapor flow through the valve
(Fig. 7).
SPECIFICATIONS
TORQUE - EVAPORATION SYSTEM
DESCRIPTION N-m Ft. Lbs. In. Lbs.
Crankcase Breathers - 3.7L /
4.7L12 - 106
EVAP Canister Mounting 11 - 100
EVAP Canister Purge
Solenoid Mounting Nuts9- 80
LDP Pump-to-Support Bracket 2 - 20
LDP Pump Support
Bracket-to-Frame28 - 250
Fig. 5 Engine Off or Engine Pop-BackÐNo Vapor
FlowFig. 6 High Intake Manifold VacuumÐMinimal Vapor
Flow
Fig. 7 Moderate Intake Manifold VacuumÐMaximum
Vapor Flow
WJEVAPORATIVE EMISSIONS 25 - 27
EVAPORATIVE EMISSIONS (Continued)