the end of the threads turn back 1/8 turn and, pull
the stem (Fig. 30) from the radiator tank.
INSTALLATION
(1) Push the draincock assembly body into the
tank opening until it snaps into place.
(2) Tighten the draincock stem by turning clock-
wise until it stops.
FAN MODULE
REMOVAL
There are no repairs to be made to the fan or
shroud assembly. If the fan is warped, cracked, or
otherwise damaged, it must be replaced as a assem-
bly (Fig. 31).
(1) Raise the vehicle on hoist.
(2) Remove the radiator outlet hose from hose
retaining clip and remove clip from shroud.
(3) Remove lower auxiliary transmission cooler
lines from retaining clips on the fan module shroud,
if equipped.
(4) Lower the vehicle. Remove the air intake res-
onator from the throttle body and air cleaner assem-
bly.
(5) Disconnect the fans electrical connector
located on the left side of the fan module.
(6) Remove the Coolant Recovery System (CRS)
attaching screw from the upper crossmember.
(7) Remove upper grill to crossmember valence
panel.
(8) Disconnect the upper radiator mounts from the
crossmember. Remove the upper crossmember. Refer
to Group 23 Body for procedure.
(9) Remove the air cleaner assembly.
(10) Remove fan module retaining fasteners (Fig.
31).
(11) Remove upper auxiliary transmission cooler
lines from retaining clips on the fan module shroud,
if equipped.(12) Disconnect and plug the transmission line
from the radiator fitting on the lower left side.
(13) Raise vehicle on the hoist and remove the fil-
ter/drier, fan module and radiator mounting bolts
located on the lower right of the module.
(14) Lower the vehicle on hoist and remove the
upper fan module to radiator retaining clips.
(15) Remove the fan module from the vehicle.
INSTALLATION
(1) Install fan module assembly into attaching
clips on the radiator.
(2) Install the upper fan module to radiator
retaining clips.
(3) Raise vehicle on the hoist and install the fil-
ter/drier, fan module and radiator mounting fasten-
ers located on the lower right of the module.
(4) Lower the vehicle. Connect the transmission
line to the radiator fitting on the lower left side.
(5) Install the upper auxiliary transmission cooler
lines to the retaining clips on the fan module shroud,
if equipped.
(6) Install fan module retaining fasteners (Fig.
31). Tighten to 12 N´m (105 in. lbs.).
(7) Install the air cleaner assembly.
(8) Install the crossmember. Refer to Group 23
Body for procedure. Connect the upper radiator
mounts to the crossmember. Tighten fasteners to 12
N´m (105 in. lbs.).
(9) Install the Coolant Recovery System (CRS)
attaching screw to the upper crossmember. Tighten
to 2 N´m (18 in. lbs.).
(10) Install upper grill to crossmember valence
panel.
(11) Connect the fans to the connector located on
the left side of the fan module.
(12) Install the air intake resonator to the throttle
body and air cleaner assembly.
Fig. 30 Draincock Disassembled
Fig. 31 Fan Module
7 - 22 COOLING SYSTEMNS
REMOVAL AND INSTALLATION (Continued)
(13) Raise the vehicle. Install the lower auxiliary
transmission cooler lines to the retaining clips on the
fan module shroud, if equipped.
(14) Install outlet hose retainer clip to the shroud.
Install the radiator outlet hose to the retaining clip.
(15) Lower the vehicle.
ENGINE BLOCK HEATER
REMOVAL
(1) Drain coolant from radiator and cylinder block.
Refer to Cooling System Drain, Clean, Flush and
Refill of this section for procedure.
(2) Remove power cord plug from heater.
(3) Loosen screw in center of heater. Remove
heater assembly.
INSTALLATION
(1) Thoroughly clean core hole and heater seat.
(2) Insert heater assembly with element loop posi-
tionedupward.
(3) With heater seated, tighten center screw
securely to assure a positive seal.
(4) Fill cooling system with coolant to the proper
level, vent air, and inspect for leaks. Pressurize sys-
tem with Radiator Pressure Tool before looking for
leaks.
(5) Install power cord plug to heater.
ACCESSORY DRIVE BELTSÐ2.4L
REMOVAL/INSTALLATION-ADJUST
GENERATOR AND AIR CONDITIONING
(1) Loosen lower generator pivot bolt and upper
locking nut, then loosen adjusting bolt (Fig. 32) to
remove belt tension.
CAUTION: Belt damage may occur if the following
procedure is not performed.
(2) Tighten lock nut to 21 N´m (180 in. lbs.) and
torque generator pivot bolt to 54 N´m (40 ft. lbs.). To
assure proper alignment of generator assembly.
Adjust belt tension by tightening the adjusting bolt
until proper belt tension is obtained. Refer to tension
specification in Belt Tension Chart.
(3) Torque lock nut to 54 N´m (40 ft. lbs.).
POWER STEERING PUMP
(1) From on top of the vehicle loosen locking nuts
D and F (Fig. 33).
(2) From under the vehicle loosen the pivot bolt E.
Loosen adjusting bolt G until belt can be removed.
(3) After installing a new belt, adjust belt tension
by tightening the adjusting bolt until the proper ten-sion obtained. Refer to tension specification in Belt
Tension Chart.
(4) Tighten locking nuts D and F to 54 N´m (40 ft.
lbs.).
(5) Tighten pivot bolt E to 54 N´m (40 ft. lbs.)
Fig. 32 Air Conditioning Compressor/Generator
BeltsÐ2.4L
Fig. 33 Power Steering Pump Adjustment
NSCOOLING SYSTEM 7 - 23
REMOVAL AND INSTALLATION (Continued)
ACCESSORY DRIVE BELTSÐ3.0L
GENERATOR/POWER STEERING PUMP BELT
REMOVAL/INSTALLATION
The Poly-V generator/power steering pump belt is
provided with a dynamic tensioner (Fig. 34) to main-
tain proper belt tension. To remove or install this
belt, apply force in a clockwise direction to the ten-
sioner pulley bolt (Fig. 34).
AIR CONDITIONING BELT
REMOVAL
To remove the air conditioning compressor drive
belt, first loosen the idler pulley lock nut, then turn
the adjusting screw to lower the idler pulley (Fig.
35).
INSTALLATION/ADJUSTMENT
To adjust the air conditioning drive belt,
loosen the idler pulley lock nut (Fig. 35) and adjust
belt tension by tightening adjusting screw. Refer toProper Belt Tension and Belt Tension Chart in this
Section for procedure. Tighten pulley lock nut to 54
N´m (40 ft. lbs.) after adjustment.
ACCESSORY DRIVE BELTÐ3.3/3.8L
REMOVE/INSTALL
GENERATOR, POWER STEERING PUMP, AIR CONDITIONING
COMPRESSOR AND WATER PUMP DRIVE BELT
The Poly-V Drive belt is provided with a dynamic
tensioner (Fig. 36) to maintain proper belt tension.
To remove or install this belt.
(1) Raise vehicle on hoist.
(2) Remove right front splash shield.
(3) Release tension by rotating the tensioner
clockwise (Fig. 36).
(4) Reverse above procedure to install.
CLEANING AND INSPECTION
WATER PUMP
Replace the water pump if it has any of the follow-
ing defects.
(1) Damage or cracks on the pump body.
(2) Coolant leaks; if the seal is leaking, this will be
evident by traces of thick deposits of greenish-brown
dried glycol running down the pump body and com-
ponents below. A thin black stain below pump weep
hole is considered normal operation.
(3) Impeller rubs inside of chain case cover
3.3/3.8L or cylinder block 2.4L engines.
(4) Excessively loose or rough turning bearing.
Fig. 34 Release Belt TensionerÐ3.0L
Fig. 35 Air Conditioning Drive BeltÐ3.0L Engine
Fig. 36 Accessory Drive BeltÐ3.3/3.8L Engines
7 - 24 COOLING SYSTEMNS
REMOVAL AND INSTALLATION (Continued)
NOTE: It is normal for the water pump to weep a
small amount of coolant from the weep hole (black
stain on water pump body). Do not replace the
water pump if this condition exists. Replace the
water pump if a heavy deposit or a steady flow of
green/brown engine coolant is evident on water
pump body from the weep hole (shaft seal failure).
Be sure to perform a thorough analysis before
replacing water pump.
ACCESSORY DRIVE BELT
When inspecting serpentine drive belts, small
cracks that run across the ribbed surface of the belt
from rib to rib (Fig. 37), are considered normal. these
are not reasons to replace the belt. However, cracks
running along the rib (not across) are not normal.
Any belt with cracks running along the rib must be
replaced (Fig. 37). Also replace the belt if it has
excessive wear, frayed cords or severe glazing.
RADIATOR PRESSURE CAP
INSPECTION
Hold the cap in hand,right side up. The vent
valve at the bottom of the cap should open. If the
rubber gasket has swollen and prevents the valve
from opening, replace the cap.
Hold the cleaned cap in handupside down.If any
light shows between vent valve and rubber gasket,
replace cap.Do not use a replacement cap that
has a spring to hold the vent shut.
Replacement cap must be of the type designed for
coolant reserve system with a completely sealed dia-
phragm spring, and rubber gasket to seal to fillerneck top surface. This design assures coolant return
to radiator.
COOLING SYSTEM CLEANING
Drain cooling system (see:Cooling System
Draining) and refill with clean water (see:Cooling
System Refilling). Run engine with radiator cap
installed until upper radiator hose is hot. Stop
engine and drain water from system. If water is
dirty; fill, run, and drain system again, until water
runs clear.
REVERSE FLUSHING THE RADIATOR
Drain cooling system and remove radiator hoses
from engine. Install suitable flushing gun in radiator
lower hose. Fill radiator with clean water and turn
on air in short blasts.
CAUTION: Internal radiator pressure must not
exceed 138 kPa (20 psi) as damage to radiator may
result. Continue this procedure until water runs
clear.
REVERSE FLUSHING THE ENGINE
Drain radiator (see:Draining Cooling System)
and remove hoses from radiator. Remove engine ther-
mostat and reinstall thermostat housing. Install suit-
able flushing gun to thermostat housing hose. Turn
on water, and when engine is filled, turn on air, but
no higher than 138 kPa (20 psi) in short blasts. Allow
engine to fill between blasts of air. Continue this pro-
cedure until water runs clean. Reinstall thermostat
using a new housing gasket. Fill cooling system (See
Refilling).
CHEMICAL CLEANING
One type of corrosion encountered with aluminum
cylinder heads is aluminum hydroxide deposits. Cor-
rosion products are carried to the radiator and depos-
ited when cooled off. They appear as dark grey when
wet and white when dry. This corrosion can be
removed with a two part cleaner (oxalic acid and
neutralizer) available in auto parts outlets. Follow
manufacturers directions for use.
ADJUSTMENTS
PROPER BELT TENSION
Satisfactory performance of the belt driven accesso-
ries depends on proper belt tension. Belt tensioning
should be performed with the aid of a Burroughs
gauge Special Tool C-4162. Because of space limita-
tions in the engine compartment, the use of the
gauge may be restricted. Raise the vehicle on a hoist
Fig. 37 Serpentine Drive Belt Wear Patterns
NSCOOLING SYSTEM 7 - 25
CLEANING AND INSPECTION (Continued)
and the remove the splash shield to gain access to
the drive belts.
BELT TENSION GAUGE METHOD
Use belt tensioning Special Tool Kit C-4162 for:
CAUTION: The Burroughs gauge for the Poly-V
belt is not to be used on the V-belt. These gauges
are not interchangeable.
²For conventional V-belts affix the Burroughs
gauge (Special Tool C-4162) to the belt. Adjust the
belt tension for New or Used belt as prescribed in the
Belt Tension Chart.
²For a Poly-V belt affix the Poly-V Burroughs
gauge to the belt and then apply specified tension to
the belt as prescribed in the Belt Tension Chart
Adjust belt tension for aNeworUsedbelt as pre-
scribed in the Belt Tension Chart.
BELT TENSION CHARTSPECIFICATIONS
COOLING SYSTEM CAPACITY
TORQUE CHART
DESCRIPTION TORQUE
Thermostat Housing
BoltsÐ2.4L & 3.3/3.8L......28N´m(250 in. lbs.)
BoltsÐ3.0L...............12N´m(105 in. lbs.)
Water Pump Mounting
BoltsÐ2.4L & 3.3/3.8L......12N´m(250 in. lbs.)
BoltsÐ3.0L...............27N´m(240 in. lbs.)
Water Pump Inlet Tube
BoltsÐ2.4L...............12N´m(250 in. lbs.)
BoltsÐ3.0L................11N´m(94in.lbs.)
Water Pump Pulley
BoltsÐ3.3/3.8L............28N´m(250 in. lbs.)
Transaxle Oil Cooler Hose
ClampsÐAll Engines.........2N´m(18in.lbs.)
Radiator Mounting Upper Bracket
NutÐAll Engines..........12N´m(105 in. lbs.)
SPECIAL TOOLS
COOLING
ACCESSORY DRIVE
BELTGAUGE
2.4L ENGINE
A/C COMPRESSOR /
GENERATORNEW 190 LB.
USED 115 LB.
POWER STEERING NEW 140 LB.
USED 90 LB.
3.0L ENGINE
A/C COMPRESSOR NEW 150 LB.
USED 80 LB.
GENERATOR / POWER
STEERINGDYNAMIC TENSIONER
3.3/3.8L ENGINES
A/C COMPRESSOR DYNAMIC TENSIONER
GENERATOR / WATER
PUMP / POWER
STEERINGDYNAMIC TENSIONER
Engine Standard Duty Trailer Tow or
Heavy Duty
Front
HeaterRear
HeaterFront
HeaterRear
Heater
2.4L 10.6
liters*
(11.23
qts.)*N/A N/A N/A
3.0L 12.3
liters*
(13.0
qts.)*N/A N/A 15.0
liters*
(15.9
qts.)*
3.3/3.8L 12.5
liters*15.26
liters*12.5
liters*15.26
liters*
(13.23
qts.)*(16.13
qts.)*(13.23
qts.)*(16.13
qts)*
*Includes Heater and Coolant Recovery Tank Filled to
Max Level.
Belt Tension Gauge C-4162
7 - 26 COOLING SYSTEMNS
ADJUSTMENTS (Continued)
COOLING SYSTEM
CONTENTS
page page
GENERAL INFORMATION
COOLANT PRESSURE BOTTLE............ 1
COOLING SYSTEM Ð 2.0L GASOLINE...... 1
COOLING SYSTEM Ð 2.5L VM DIESEL..... 1
LOW COOLANT LEVEL SENSOR........... 1
RADIATOR............................ 2
DESCRIPTION AND OPERATION
AUTOMATIC BELT TENSIONER............ 6
BELT TENSION......................... 5
COOLANT PERFORMANCE............... 5
PRESSURE/VENT CAP................... 4
THERMOSTAT OPERATION............... 4
THERMOSTAT......................... 6
WATER PUMP......................... 3
SERVICE PROCEDURES
ADDING ADDITIONAL COOLANT........... 7
DRAINING COOLING SYSTEM............. 7
REFILLING COOLING SYSTEM............ 7
REMOVAL AND INSTALLATION
ENGINE THERMOSTATÐ 2.0L GASOLINE . . . 9GENERATOR/POWER STEERING BELT Ð 2.5L
VM DIESEL......................... 10
RADIATOR Ð 2.5L VM DIESEL........... 9
THERMOSTAT Ð 2.5L VM DIESEL......... 9
WATER PUMP BELT Ð 2.5L VM DIESEL . . . 10
WATER PUMP Ð 2.0L GASOLINE......... 7
WATER PUMP Ð 2.5L VM DIESEL........ 8
CLEANING AND INSPECTION
WATER PUMP........................ 10
ADJUSTMENTS
BELT TENSION CHART................. 11
BELT TENSION GAUGE METHOD......... 11
SPECIFICATIONS
COOLING SYSTEM CAPACITY............ 12
TORQUE CHART...................... 12
SPECIAL TOOLS
COOLING............................ 12
GENERAL INFORMATION
COOLING SYSTEM Ð 2.0L GASOLINE
The 2.0L gasoline engine cooling system consists of
an engine cooling module, thermostat, coolant, a
water pump to circulate the coolant. The engine cool-
ing module may consist of a radiator, electric fan
motors, fan, shroud, coolant reserve system, hoses,
clamps, air condition condenser.
²When the Engine is cold: The thermostat is
closed; the cooling system has no flow through the
radiator. The coolant flows through the engine,
heater system and bypass.
²When the Engine is warm: Thermostat is open;
the cooling system has flow through radiator, engine,
heater system and bypass.
COOLING SYSTEM Ð 2.5L VM DIESEL
The cooling system has a radiator, coolant, electric
fan motors, shroud, pressure cap, thermostat, coolant
pressure bottle, hoses, a water pump to circulate the
coolant, to complete the circuit. Coolant flow for the
VM diesel engine is shown in (Fig. 1).
COOLANT PRESSURE BOTTLE
2.5L VM DIESEL
This system works with the pressure cap to use
thermal expansion and contraction of the coolant to
keep the coolant free of trapped air. It provides some
reserve coolant to cover minor leaks and evaporation
or boiling losses. The coolant pressure bottle location
for 2.5L diesel is above the cylinder head cover (Fig.
2).
LOW COOLANT LEVEL SENSOR
The low coolant level sensor checks for low coolant
level in the coolant tank. A signal will be sent from
this sensor to the Body Control Module (BCM). When
the BCM determines low coolant level for 30 contin-
uous seconds, the instrument panel mounted low
coolant level warning lamp will be illuminated. The
sensor is located on the front side of the coolant tank
(Fig. 4). For information, refer to Group 8E, Instru-
ment Panel and Gauges.
If this lamp is illuminated, it indicates the need to
fill the coolant tank and check for leaks.
NS/GSCOOLING SYSTEM 7 - 1
RADIATOR
The radiators are cross-flow types (horizontal
tubes) with design features that provide greater
strength along with sufficient heat transfer capabili-
Fig. 1 Cooling System Operation ± 2.5L VM Diesel
Fig. 2 Coolant Pressure Bottle ± 2.5L VM Diesel
Fig. 3 Low Coolant Warning Sensor Connector ±
2.5L VM Diesel
7 - 2 COOLING SYSTEMNS/GS
GENERAL INFORMATION (Continued)
ties to keep the engine satisfactorily cooled (Fig. 5)
and (Fig. 6).
CAUTION: Plastic tanks, while stronger then brass
are subject to damage by impact, such as wrenches
etc., or by excessive torque on hose clamps.
If the plastic tank is damaged, replace the radia-
tor.
DESCRIPTION AND OPERATION
WATER PUMP
2.0L GASOLINE
The water has a diecast aluminum body and hous-
ing with a stamped steel impeller. The water pumpbolts directly to the block (Fig. 7). Cylinder block to
water pump sealing is provided by a rubber O-ring.
The water pump is driven by the timing belt. Refer
to Group 9, Engine section for component removal to
access the water pump.
NOTE: The water pump on all models can be
replaced without discharging the air conditioning
system.
2.5L VM DIESEL
The Diesel engine water pump has an aluminum
body and housing with a stamped steel impeller. The
pump uses an O-ring gasket between body and hous-
ing. The water pump is driven by the accessory drive
belt, and the pump housing is bolted to the cylinder
block (Fig. 9).
NOTE: The water pump on all models can be
replaced without discharging the air conditioning
system.
Fig. 4 Low Coolant Level Sensor
Fig. 5 Cooling Module Ð2.0LGasoline
Fig. 6 Cooling Module ÐVM Diesel
NS/GSCOOLING SYSTEM 7 - 3
GENERAL INFORMATION (Continued)