
If the gasket is dirty or damaged, a vacuum
may not be achieved, resulting is loss of coolant
and eventual overheating due to low coolant
level in radiator and engine.
ENGINE BLOCK HEATER
The engine block heater is available as an optional
accessory on all models. The heater is operated by
ordinary house current (110 Volt A.C.) through a
power cord located behind the radiator grille. This
provides easier engine starting and faster warm-up
when vehicle is operated in areas having extremely
low temperatures. The heater is mounted in a core
hole (in place of a core hole plug) in the engine block,
with the heating element immersed in coolant.
Fig. 7 Cooling ModuleÐ3.0L (Front A/C Only)
Fig. 8 Cooling ModuleÐ3.0/3.3/3.8L (With Rear A/C)
Fig. 9 Radiator Pressure Cap Filler Neck
NSCOOLING SYSTEM 7 - 5
GENERAL INFORMATION (Continued)

DESCRIPTION AND OPERATION
WATER PIPESÐ3.0L ENGINE
The 3.0L engine uses metal piping beyond the
lower radiator hose to route (suction) coolant to the
water pump, which is located in the V of the cylinder
banks (Fig. 10).
These pipes are provided with inlet nipples for
thermostat bypass and heater return coolant hoses,
and brackets for rigid engine attachment. The pipes
employ O-rings for sealing at their interconnection
and to the water pump (Fig. 10).
COOLANT PERFORMANCE
Performance is measurable. For heat transfer pure
water excels (Formula = 1 btu per minute for each
degree of temperature rise for each pound of water).
This formula is altered when necessary additives to
control boiling, freezing, and corrosion are added as
follows:
²Pure Water (1 btu) boils at 100ÉC (212ÉF) and
freezes at 0ÉC (32ÉF)
²100 percent Glycol (.7 btu) can cause a hot
engine and detonation and will lower the freeze point
to -22ÉC (-8ÉF).
²50/50 Glycol and Water (.82 btu) is the recom-
mended combination that provides a freeze point of
-37ÉC (-35ÉF). The radiator, water pump, engine
water jacket, radiator pressure cap, thermostat, tem-
perature gauge, sending unit and heater are all
designed for 50/50 glycol.CAUTION: Do not use well water, or suspect water
supply in cooling system. A 50/50 ethylene glycol
and distilled water mix is recommended.
Where required, a 56 percent glycol and 44 percent
water mixture will provide a freeze point of -59ÉC
(-50ÉF).
CAUTION: Richer mixtures cannot be measured
with field equipment. This can lead to problems
associated with 100 percent glycol.
RADIATOR HOSES AND CLAMPS
WARNING: IF VEHICLE HAS BEEN RUN
RECENTLY, WAIT 15 MINUTES BEFORE WORKING
ON VEHICLE. RELIEVE PRESSURE BY PLACING A
SHOP TOWEL OVER THE CAP AND WITHOUT
PUSHING DOWN ROTATE IT COUNTERCLOCKWISE
TO THE FIRST STOP. ALLOW FLUIDS AND STEAM
TO ESCAPE THROUGH THE OVERFLOW TUBE.
THIS WILL RELIEVE SYSTEM PRESSURE
The hoses are removed by using constant tension
clamp pliers to compress the hose clamp.
A hardened, cracked, swollen or restricted hose
should be replaced. Do not damage radiator inlet and
outlet when loosening hoses.
Radiator hoses should be routed without any kinks
and indexed as designed. The use of molded hoses is
recommended.
Spring type hose clamps are used in all applica-
tions. If replacement is necessary replace with the
original MOPARtequipment spring type clamp.
WATER PUMPÐ2.4L ENGINE
The water pump has a diecast aluminum body and
housing with a stamped steel impeller. The water
pump bolts directly to the block. Cylinder block to
water pump sealing is provided by a rubber O-ring.
The water pump is driven by the timing belt. Refer
to Timing Belt in Group 9, Engine for component
removal providing access to water pump.
WATER PUMPÐ3.0L ENGINE
The pump bolts directly to the engine block, using
a gasket for pump to block sealing (Fig. 11). The
pump is serviced as a unit.
The water pump is driven by the timing belt. See
Timing Belt in Group 9, Engine for component
removal providing access to water pump.
Fig. 10 Engine Inlet Coolant Pipes 3.0L Engine
7 - 6 COOLING SYSTEMNS

WARNING: WITH TOOL IN PLACE, PRESSURE
WILL BUILD UP FAST. EXCESSIVE PRESSURE
BUILT UP, BY CONTINUOUS ENGINE OPERATION,
MUST BE RELEASED TO A SAFE PRESSURE
POINT. NEVER PERMIT PRESSURE TO EXCEED 138
kPa (20 psi).
If the needle on the dial does not fluctuate, race
the engine a few times. If an abnormal amount of
coolant or steam emits from the tail pipe, it may
indicate a coolant leak caused by a faulty head gas-
ket, cracked engine block, or cracked cylinder head.
There may be internal leaks that can be deter-
mined by removing the oil dipstick. If water globules
appear intermixed with the oil it will indicate an
internal leak in the engine. If there is an internal
leak, the engine must be disassembled for repair.
RADIATOR CAP TO FILLER NECK SEAL PRESSURE
RELIEF CHECK
The pressure cap upper gasket (seal) pressure
relief can be checked by removing the overflow hose
at the radiator filler neck nipple (Fig. 13). Attach the
Radiator Pressure Tool to the filler neck nipple and
pump air into the radiator. Pressure cap upper gas-
ket should relieve at 69-124 kPa (10-18 psi) and hold
pressure at 55 kPa (8 psi) minimum.
WARNING: THE WARNING WORDS ªDO NOT
OPEN HOTº ON THE RADIATOR PRESSURE CAP IS
A SAFETY PRECAUTION. WHEN HOT, PRESSURE
BUILDS UP IN COOLING SYSTEM. TO PREVENT
SCALDING OR INJURY, THE RADIATOR CAP
SHOULD NOT BE REMOVED WHILE THE SYSTEM
IS HOT OR UNDER PRESSURE.
There is no need to remove the radiator cap at any
timeexceptfor the following purposes:
(1) Check and adjust coolant freeze point. By add-
ing or subtracting coolant through CRS bottle.
(2) Refill system with new coolant.
(3) Conducting service procedures.
(4) Checking for vacuum leaks.WARNING: IF VEHICLE HAS BEEN RUN
RECENTLY, WAIT 15 MINUTES BEFORE REMOVING
CAP. THEN PLACE A SHOP TOWEL OVER THE CAP
AND WITHOUT PUSHING DOWN ROTATE COUN-
TERCLOCKWISE TO THE FIRST STOP. ALLOW FLU-
IDS TO ESCAPE THROUGH THE OVERFLOW TUBE
AND WHEN THE SYSTEM STOPS PUSHING COOL-
ANT AND STEAM INTO THE CRS TANK AND PRES-
SURE DROPS PUSH DOWN AND REMOVE THE CAP
COMPLETELY. SQUEEZING THE RADIATOR INLET
HOSE WITH A SHOP TOWEL (TO CHECK PRES-
SURE) BEFORE AND AFTER TURNING TO THE
FIRST STOP IS RECOMMENDED.
PRESSURE TESTING RADIATOR CAP
Dip the pressure cap in water, clean any deposits
off the vent valve or its seat and apply cap to end of
Radiator Pressure Tool. Working the plunger, bring
the pressure to 104 kPa (15 psi) on the gauge. If the
pressure cap fails to hold pressure of at least 97 kPa
(14 psi) replace cap. SeeCAUTION.
If the pressure cap tests properly while positioned
on Radiator Pressure Tool (Fig. 14), but will not hold
pressure or vacuum when positioned on the radiator.
Inspect the radiator filler neck and cap top gasket for
irregularities that may prevent the cap from sealing
properly.
CAUTION: Radiator Pressure Tool is very sensitive
to small air leaks that will not cause cooling system
problems. A pressure cap that does not have a his-
tory of coolant loss should not be replaced just
because it leaks slowly when tested with this tool.
Add water to the tool. Turn tool upside down and
recheck pressure cap to confirm that cap is bad.
LOW COOLANT LEVEL AERATION
Low coolant level in a cross flow radiator will
equalize in both tanks with engine off. With engine
Fig. 13 Radiator Pressure Cap Filler Neck
Fig. 14 Pressure Testing Radiator Cap
NSCOOLING SYSTEM 7 - 15
DIAGNOSIS AND TESTING (Continued)

at running operating temperature the high pressure
inlet tank runs full and the low pressure outlet tank
drops:
²Transmission oil will become hotter.
²High reading shown on the temperature gauge.
²Air in the coolant can cause loss of flow through
the heater.
²Exhaust gas leaks into the coolant also can
cause the same problems.
DEAERATION
Air can only be removed from the system by gath-
ering under the pressure cap. On the next heat up it
will be pushed past the pressure cap into the CRS
tank by thermal expansion of the coolant. It then
escapes to the atmosphere in the CRS tank and is
replaced with solid coolant on cool down.
TEMPERATURE GAUGE INDICATION
At idle with Air Conditioning off the temperature
gauge will rise slowly to about 5/8 gauge travel, the
fan will come on and the gauge will quickly drop to
about 1/2 gauge travel. This is normal.
SERVICE PROCEDURES
COOLANT LEVEL CHECKÐROUTINE
Do not remove radiator cap for routine cool-
ant level inspections.
The coolant reserve system provides a quick visual
method for determining the coolant level without
removing the radiator cap.With the engine cold
and not running,simply observe the level of the
coolant in the reserve tank (Fig. 3). The coolant level
should be between the minimum and maximum
marks.
COOLANTÐADDING ADDITIONAL
The radiator cap should not be removed.
When additional coolant is needed to maintain this
level, it should be added to the coolant reserve tank.
Use only 50/50 mix of ethylene glycol type antifreeze
and water.
CAUTION: Do not use well water, or suspect water
supply in cooling system. A 50/50 ethylene glycol
and distilled water mix is recommended.
COOLANT LEVEL SERVICE
The cooling system is closed and designed to main-
tain coolant level to the top of the radiator.
When servicing requires a coolant level check in
the radiator, the engine must beoffandnotunder
pressure. Drain several ounces of coolant from the
radiator draincock while observing the CoolantRecovery System (CRS) Tank. Coolant level in the
CRS tank should drop slightly. Then remove the radi-
ator cap. The radiator should be full to the top. If
not, and the coolant level in the CRS tank is at the
MIN mark there is an air leak in the CRS system.
Check hose or hose connections to the CRS tank,
radiator filler neck or the pressure cap seal to the
radiator filler neck for leaks.
COOLING SYSTEMÐDRAINING
Without removing radiator pressure cap and
with system not under pressure,shut engine off
and open draincock. The coolant reserve tank should
empty first, then remove radiator pressure cap. (if
not, see Testing Cooling System for leaks). To vent
2.4L engine remove the coolant temperature sensor
located above water outlet housing (Fig. 15). The 3.0/
3.3/3.8L engines have an air bleed vent on the ther-
mostat.
Removal of a sensor is required because the ther-
mostat does not have an air vent. Sensor removal
allows an air bleed for coolant to drain from the
engine block.
COOLING SYSTEMÐREFILLING
First clean system to remove old coolant, see Cool-
ing System Cleaning.
Fill the system, using the correct antifreeze as
described in the Coolant Section. Fill the system to
50 percent of its capacity with 100 percent glycol.
Then complete filling system with water. The 2.4L
engine requires venting by removal of the coolant
sensor on top of the water outlet connector (Fig. 15).
When coolant reaches this hole:
²Install coolant sensor and tighten to 7 N´m (60
in. lbs.) for 2.4L Engines.
Fig. 15 Coolant Temperature SensorÐ2.4L Engine
Drain/Fill
7 - 16 COOLING SYSTEMNS
DIAGNOSIS AND TESTING (Continued)

Continue filling system until full, this provides bet-
ter heater performance.Be careful not to spill
coolant on drive belts or the generator.
Fill coolant reserve system to at least the MAX
mark with 50/50 solution. It may be necessary to add
coolant to the reserve tank after three or four warm
up/cool down cycles to maintain coolant level between
the MAX and MIN mark. This will allow trapped air
to be removed from the system.
REMOVAL AND INSTALLATION
WATER PUMPÐ2.4L ENGINE
REMOVAL
(1) Disconnect negative cable from battery.
(2) Raise vehicle on a hoist. Remove right inner
splash shield.
(3) Remove accessory drive belts. Refer to Acces-
sory Drive Belt service in this section.
(4) Drain cooling system. Refer to Cooling System
Draining in this section.
(5) Support engine from the bottom and remove
right engine mount.
(6) Remove right engine mount bracket.
(7) Remove timing belt. Refer to Group 9, Engine
for procedure.
(8) Remove timing belt idler pulley.
(9) Hold camshaft sprocket with Special tool
C-4687 and adaptor C-4687-1 while removing bolt.
Remove both cam sprockets.
(10) Remove rear timing belt cover.
(11) Remove water pump attaching screws to
engine (Fig. 16).
INSTALLATION
(1) Install new O-ring gasket in water pump body
O-ring groove (Fig. 17).
CAUTION: Make sure O-ring is properly seated in
water pump groove before tightening screws. An
improperly located O-ring may cause damage to the
O-ring and cause a coolant leak.(2) Assemble pump body to block and tighten
screws to 12 N´m (105 in. lbs.) (Fig. 16). Pressurize
cooling system to 15 psi with pressure tester and
check water pump shaft seal and O-ring for leaks.
(3) Rotate pump by hand to check for freedom of
movement.
(4) Install rear timing belt cover.
(5) Install camshaft sprockets and torque bolts to
101 N´m (75 ft. lbs.).
(6) Install timing belt idler pulley and torque
mounting bolt to 61 N´m (45 ft. lbs.).
(7) Install timing belt. Refer to Group 9, Engine,
2.4L Timing Belt.
(8) Install right engine mount bracket and engine
mount. Refer to Group 9 for procedure.
(9) Fill cooling system. SeeCooling System Fill-
ing.
(10) Install accessory drive belts, Refer to Acces-
sory Drive Belts, in this section.
(11) Lower vehicle and connect battery cable.
WATER PUMP INLET TUBEÐ2.4L ENGINE
REMOVAL
(1) Drain cooling system. Refer to procedure out-
lined in this section.
(2) Remove upper radiator hose to access the hose
connections at the inlet tube.
(3) Remove lower radiator hose and heater hose
from the inlet tube (Fig. 18).
(4) Remove the 2 fasteners that hold the inlet
tube to the block.
(5) Rotate tube while removing the tube from the
engine block (Fig. 19).
INSTALLATION
(1) Inspect the O-ring for damage before installing
the tube into the cylinder block (Fig. 19).
(2) Lube O-ring with coolant and install into the
cylinder block opening.
(3) Install 2 fasteners and tighten to 12 N´m (105
in. lbs.).
(4) Connect lower radiator hose and heater hose
to inlet tube (Fig. 18).
Fig. 16 Water PumpÐ2.4L Engine
Fig. 17 Water Pump Body
NSCOOLING SYSTEM 7 - 17
SERVICE PROCEDURES (Continued)

INSTALLATION
(1) Clean all gasket and O-ring surfaces on pump
and water pipe inlet tube.
(2) Install new O-ring on water inlet pipe (Fig.
22). Wet the O-ring (with water) to ease assembly.
CAUTION: Keep the O-ring free of oil or grease.
(3) Install new gasket on water pump and install
pump inlet opening over water pipe, press assembly
to cause water pipe insertion into pump housing.
(4) Install pump to block mounting bolts and
tighten to 27 N´m (20 ft. lbs.).
(5) See Timing Belt in Engine, Group 9 and
install timing belt. Reassemble engine.
(6) Fill cooling system. See Refilling Cooling Sys-
tem.
WATER PUMPÐ3.3/3.8L ENGINES
REMOVAL
(1) Drain Cooling System. Refer to Draining Cool-
ing System in this group.
(2) Remove Poly-V Drive Belt.
(3) Remove right front lower fender shield.
(4) Remove pump pulley bolts and remove pulley.
(5) Remove pump mounting screws (Fig. 23).
Remove water pump.
(6) Remove and discard O-ring seal.
(7) Clean O-ring groove and O-ring surfaces on
pump and chain case cover. Take care not to scratch
or gouge sealing surface.
INSTALLATION
(1) Install new O-ring into groove (Fig. 24).
(2) Install pump to chain case cover. Torque
screws to 12 N´m (105 in. lbs.)
(3) Rotate pump by hand to check for freedom of
movement.(4) Position pulley on pump. Install screws and
torque to 30 N´m (250 in. lbs.).
(5) Install drive belt. See Accessory Drive Belts in
this group.
(6) Install right front lower fender shield.
(7) Refill Cooling System. See Refilling Cooling
System.
THERMOSTATÐ2.4L ENGINE
REMOVAL
(1) Drain cooling system down below the thermo-
stat level. Refer to Draining Cooling System in this
group.
(2) Remove thermostat housing bolts and housing
(Fig. 25).
(3) Remove thermostat, discard gasket and clean
both gasket sealing surfaces.
Fig. 23 Water Pump Ð3.3/3.8L Engines
Fig. 24 Water Pump Body
Fig. 25 Thermostat, Housing, and Outlet
ConnectorÐ2.4L Engine
NSCOOLING SYSTEM 7 - 19
REMOVAL AND INSTALLATION (Continued)

INSTALLATION
(1) Place a new gasket (dipped in water) on the
thermostat housing surface, center thermostat into
opening in the intake manifold water box.
(2) Place housing and gasket over the thermostat,
making sure thermostat is in the recess provided
(Fig. 28).
(3) Bolt housing to intake manifold, tighten bolts
to 28 N´m (250 in. lbs.).
(4) Refill the cooling system to the proper level.
Refer to Cooling System Refilling outlined in this sec-
tion for procedure.
RADIATOR
REMOVAL
(1) Disconnect negative cable from battery.
WARNING: DO NOT REMOVE THE CYLINDER
BLOCK PLUG OR THE RADIATOR DRAINCOCK
WITH THE SYSTEM HOT AND UNDER PRESSURE
BECAUSE SERIOUS BURNS FROM COOLANT CAN
OCCUR.
(2) Drain cooling system. Refer to Draining Cool-
ing System of this section.
(3) Remove air intake resonator.
(4) Remove coolant reserve system tank to filler
neck tube hose.
(5) Disconnect fans from the connector located on
the left side of the fan module.
(6) Remove the Coolant Recovery System (CRS)
tank retaining screw from the upper radiator closure
panel crossmember.
(7) Disconnect the upper radiator mounting
screws from the crossmember. Disconnect the engine
block heater wire if equipped.
(8) Remove the upper radiator closure panel
crossmember. Refer to Group 23 Body for procedure.
(9) Remove air cleaner assembly.
(10) Disconnect automatic transmission oil cooler
lines at radiator and plug.
(11) Disconnect inlet and outlet hoses from the
radiator. Remove the lower hose clip from the fan
module.
(12) Remove A/C condenser fasteners and sepa-
rate the condenser from the radiator (Fig. 29). Verify
the condenser is supported in position.
(13) Remove A/C filter/dryer mounting bracket, 2
bolts to the fan module, and 2 nuts to the filter/dryer.
(14) Radiator can now be lifted free from engine
compartment.Care should be taken not to dam-
age radiator cooling fins or water tubes during
removal.INSTALLATION
(1)Be sure the air seals are in position before
radiator is installed.Slide radiator down into posi-
tion behind closure panel. Seat the radiator with the
rubber isolators into the mounting holes provided,
with a 10 lbs. force.
(2) Install A/C filter/dryer and mounting bracket
onto fan module.
(3) Install Air Conditioning Condenser onto the
radiator (Fig. 29).
(4) Unplug and connect automatic transmission
oil cooler lines to radiator.
(5) Install inlet and outlet radiator hoses (includ-
ing coolant reserve hose) and connect the fan motor
electrical connection.
(6) Install air cleaner assembly.
(7) Install the upper radiator closure panel cross-
member. Refer to Group 23 Body for procedure.
(8) Install the upper radiator mounting screws.
Tighten radiator mounting bolts to 12 N´m (105 in.
lbs.). Connect the engine block heater wire if
equipped.
(9) Install the Coolant Recovery System (CRS)
tank retaining screw to the upper radiator closure
panel crossmember.
(10) Install air intake resonator.
(11) Fill cooling system. Refer to Cooling System
Filling in this section.
(12) Connect negative cable to battery.
RADIATOR DRAINCOCK
REMOVAL
CAUTION: Use of pliers on draincock is not rec-
ommended. Damage may occur to part. Draincock
should not be removed unless leakage observed.
(1) Turn the draincock stem counterclockwise to
unscrew the stem. When the stem is unscrewed to
Fig. 29 Air Conditioning Condenser Mounting
Fasteners
NSCOOLING SYSTEM 7 - 21
REMOVAL AND INSTALLATION (Continued)

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)