²Corrosion in the cooling system.
²Water pump seal may run dry, increasing the
risk of premature seal failure.
²Combustion gas leaks into the coolant can also
cause the above problems.
DIAGNOSIS AND TESTING - COOLING SYSTEM
DEAERATION
Air can only be removed from the system by gather-
ing under the pressure cap. On the next heat up it will
be pushed past the pressure cap into the coolant recov-
ery bottle by thermal expansion of the coolant. It then
escapes to the atmosphere in the coolant recovery bottle
and is replaced with coolant on cool down.
To effectively deaerate the system, multiple ther-
mal cycles of the system may be required.
NOTE: Deaeration does not occur at engine idleÐ
higher engine speeds are required. Normal driving
will deaerate cooling system.
STANDARD PROCEDURE
STANDARD PROCEDURE - COOLING SYSTEM
DRAINING
WARNING: DO NOT REMOVE OR LOOSEN THE
COOLANT PRESSURE CAP, CYLINDER BLOCK
DRAIN PLUGS, OR THE DRAINCOCK WHEN THESYSTEM IS HOT AND UNDER PRESSURE
BECAUSE SERIOUS BURNS FROM THE COOLANT
CAN OCCUR.
(1)Without removing radiator pressure cap
and with system not under pressure, open the
draincock. The draincock is located on the lower left
side of radiator (Fig. 5).
(2) After the coolant recovery/reserve container is
empty, then remove coolant pressure cap (Fig. 6).
(3) Remove the cylinder block drain plug(s).
Fig. 6 Cooling System Service Locations
1 - COOLANT RECOVERY CONTAINER 3 - ENGINE OIL LEVEL DIPSTICK
2 - ENGINE OIL FILL CAP 4 - RADIATOR PRESSURE CAP
Fig. 5 Draincock Location
1 - LEFT SIDE FRAME RAIL
2 - DRAINCOCK
7 - 4 COOLINGRS
COOLING (Continued)
ProCarManuals.com
STANDARD PROCEDURE - COOLING SYSTEM
FILLING
Remove radiator pressure cap (Fig. 6) and fill sys-
tem, using a 50/50 mix of MopartAntifreeze/Coolant,
5 Year/100,000 Mile Formula and distilled water.
Continue filling system until full.Be careful not
to spill coolant on drive belts or the generator.
For cooling system capacity, (Refer to LUBRICATION
& MAINTENANCE/FLUID CAPACITIES - SPECIFI-
CATIONS).
Fill coolant recovery/reserve container (Fig. 6) to at
least the MAX mark with 50/50 solution. It may be
necessary to add coolant to the recovery/reserve con-
tainer 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.
STANDARD PROCEDURE - ADDING
ADDITIONAL COOLANT
The radiator cap should not be removed.
When additional coolant is needed to maintain this
level, it should be added to the coolant recovery/re-
serve container (Fig. 6). Use only 50/50 mix of ethyl-
ene glycol type antifreeze and distilled water. For the
recommeded antifreeze/coolant type (Refer to LUBRI-
CATION & MAINTENANCE/FLUID TYPES -
DESCRIPTION).
CAUTION: Do not use well water, or suspect water
supply in cooling system. A 50/50 ethylene glycol
and distilled water mix is recommended. For the
recommeded antifreeze/coolant type (Refer to
LUBRICATION & MAINTENANCE/FLUID TYPES -
DESCRIPTION).
STANDARD PROCEDURE - COOLANT LEVEL
CHECK
NOTE: 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 recovery/reserve container (Fig. 6). The
coolant level should be between the MIN and MAX
marks.
SPECIFICATIONS
ACCESSORY DRIVE BELT TENSION
ACCESSORY DRIVE BELT TENSION
2.4L ENGINE
Air Conditioning
Compressor/GeneratorDynamic Tensioner
Power
SteeringNew Belt534 - 756 N
(120 - 170 lbs.)
Used Belt*356 - 534 N
(80 - 120 lbs)
*Belt is considered used after 15 minutes of run-in
time
3.3/3.8L ENGINES
Air Conditioning Compressor
Dynamic Tensioner
Generator/Water Pump/
Power Steering
TORQUE
DESCRIPTION N´mFt.
Lbs.In.
Lbs.
Accessory Drive Belt Tensioner
Assembly (3.3/3.8L)ÐBolt28 Ð 250
Engine Coolant Temperature
Sensor
(2.4 & 3.3/3.8L) 7 Ð 60
Generator & A/C Compressor
Drive Belt Tensioner Assembly
(2.4L)ÐBolt54 40 Ð
Coolant Outlet Connector/
Thermostat Housing
(2.4 & 3.3/3.8L)ÐBolts 28 Ð 250
Water Pump
(2.4 & 3.3/3.8L)ÐBolts 12 Ð 105
Water Pump Inlet Tube
(2.4L)ÐBolts12 Ð 105
Water Pump Inlet Tube
(3.3/3.8L)ÐBolts28 Ð 250
Water Pump Pulley (3.3/3.8L)Ð
Bolts28 Ð 250
Radiator to A/C CondenserÐ
Screws5Ð45
Radiator FanÐScrews 5 Ð 45
Radiator Mounting (Upper
Bracket)ÐNuts12 Ð 105
RSCOOLING7-5
COOLING (Continued)
ProCarManuals.com
ENGINE
TABLE OF CONTENTS
page page
ENGINE
DIAGNOSIS AND TESTING - ENGINE
COOLING SYSTEM....................14
CLEANING............................18
INSPECTION..........................18
COOLANT
DESCRIPTION - ENGINE COOLANT.........19
DIAGNOSIS AND TESTING - COOLANT
CONCENTRATION TESTING.............19
STANDARD PROCEDURE - COOLANT
SERVICE............................19
COOLANT RECOVERY CONTAINER
DESCRIPTION.........................19
OPERATION...........................19
DIAGNOSIS AND TESTING - COOLANT
RECOVERY SYSTEM..................20
REMOVAL.............................20
INSTALLATION.........................20
ENGINE BLOCK HEATER
DESCRIPTION.........................20
OPERATION...........................20
DIAGNOSIS AND TESTING - ENGINE BLOCK
HEATER TESTING.....................20
REMOVAL.............................20
INSTALLATION.........................20
ENGINE COOLANT TEMPERATURE SENSOR -
2.4L
DESCRIPTION.........................21
REMOVAL.............................21
INSTALLATION.........................21
ENGINE COOLANT TEMPERATURE SENSOR -
3.3/3.8L
DESCRIPTION.........................21
REMOVAL.............................21
INSTALLATION.........................22
ENGINE COOLANT THERMOSTAT
DESCRIPTION.........................22
OPERATION...........................22
DIAGNOSIS AND TESTING - ENGINE
COOLANT THERMOSTAT...............23
ENGINE COOLANT THERMOSTAT - 2.4L
REMOVAL.............................23
INSTALLATION.........................23
ENGINE COOLANT THERMOSTAT - 3.3/3.8L
REMOVAL.............................23
INSTALLATION.........................24
RADIATOR
REMOVAL.............................25INSTALLATION.........................25
RADIATOR DRAINCOCK
REMOVAL.............................26
INSTALLATION.........................26
RADIATOR PRESSURE CAP
DESCRIPTION.........................26
OPERATION...........................27
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - COOLING
SYSTEM PRESSURE CAP TESTING.......27
DIAGNOSIS AND TESTING - RADIATOR
CAP TO FILLER NECK SEAL.............27
CLEANING............................28
INSPECTION..........................28
RADIATOR FAN
DESCRIPTION.........................28
OPERATION...........................29
DIAGNOSIS AND TESTING - RADIATOR FAN
MOTOR .............................29
REMOVAL.............................30
INSTALLATION.........................30
RADIATOR FAN RELAY
DESCRIPTION.........................30
OPERATION...........................30
REMOVAL.............................30
INSTALLATION.........................30
WATER PUMP - 2.4L
DESCRIPTION.........................31
REMOVAL.............................31
CLEANING............................32
INSPECTION..........................32
INSTALLATION.........................32
WATER PUMP - 3.3/3.8L
DESCRIPTION.........................33
REMOVAL.............................33
CLEANING............................34
INSPECTION..........................34
INSTALLATION.........................34
WATER PUMP INLET TUBE - 2.4L
DESCRIPTION.........................35
REMOVAL.............................35
INSTALLATION.........................35
WATER PUMP INLET TUBE - 3.3/3.8L
REMOVAL.............................36
INSTALLATION.........................36
RSENGINE7-13
ProCarManuals.com
ENGINE
DIAGNOSIS AND TESTING - ENGINE COOLING
SYSTEM
Establish what driving condition caused the cooling
system complaint. The problem may be caused by an
abnormal load on the system such as the following:
prolonged idle, very high ambient temperature, slight
tail wind at idle, slow traffic speed, traffic jam, high
speed, steep grade.
DRIVING TECHNIQUES
To avoid overheating the cooling system:
(1) Idle with A/C off when temperature gauge is at
end of normal range.
(2) Do not increase engine speed for more air flow
and coolant flow because the electric motor fan sys-
tems are not responsive to engine RPM. The added
cooling from higher coolant flow rate is more than
offset by increased heat rejection (engine heat added
to coolant).
TRAILER TOWING
Consult the owner's manual under Trailer Towing
and do not exceed specified limits.
VISUAL INSPECTION
If the cooling system problem is not caused by a
driving condition, perform a visual inspection to
determine if there was a recent service or accident
repair, including the following:
²Loose/damaged water pump drive belt
²Incorrect cooling system refilling (trapped air or
low level)
²Brakes possibly dragging
²Damaged hoses
²Loose/damaged hose clamps
²Damaged/incorrect engine thermostat
²Damaged cooling fan motor, fan blade and fan
shroud
²Damaged head gasket
²Damaged water pump
²Damaged radiator
²Damaged coolant recovery system
²Damaged heater core
²Open/shorted electrical circuits
If the visual inspection reveals none of the above
as cause for a cooling system complaint, refer to the
following diagnostic charts.
COOLING SYSTEM DIAGNOSIS CHART
CONDITION POSSIBLE CAUSES CORRECTION
PRESSURE CAP IS BLOWING
OFF STEAM AND/OR COOLANT.
TEMPERATURE GAUGE READING
MAY BE ABOVE NORMAL BUT
NOT HIGH. COOLANT LEVEL MAY
BE HIGH IN COOLANT RESERVE/
OVERFLOW TANK.1. Pressure relief valve in radiator
cap is defective, or was not
properly seated.1. Check condition of radiator cap
and cap seal. (Refer to 7 -
COOLING/ENGINE/RADIATOR
PRESSURE CAP - DIAGNOSIS
AND TESTING) Replace cap as
necessary.
2. Incorrect cap was installed. 2. Replace cap as necessary.
3. Incorrect coolant mixture. 3. Check concentration level of the
coolant. (Refer to 7 - COOLING/
ENGINE/COOLANT - DIAGNOSIS
AND TESTING) Adjust the ethylene
glycol-to-water ratio as required.
COOLANT LOSS TO THE
GROUND WITHOUT PRESSURE
CAP BLOWOFF. GAUGE IS
READING HIGH OR HOT.1. Coolant leaks in radiator, cooling
system hoses, water pump or
engine.1. Pressure test and repair as
necessary. (Refer to 7 - COOLING -
DIAGNOSIS AND TESTING)
7 - 14 ENGINERS
ProCarManuals.com
CONDITION POSSIBLE CAUSES CORRECTION
DETONATION OR PRE-IGNITION
(NOT CAUSED BY IGNITION
SYSTEM). GAUGE MAY NOT BE
READING HIGH.1. Engine overheating. 1. Check reason for overheating
and repair as necessary.
2. Freeze point of coolant not
correct. Mixture too concentrated or
too diluted.2. Check concentration level of the
coolant. (Refer to 7 - COOLING/
ENGINE/COOLANT - DIAGNOSIS
AND TESTING) Adjust the ethylene
glycol-to-water ratio as required.
3. Incorrect cooling system
pressure cap.3. Install correct pressure cap.
HOSE(S) COLLAPSE AS ENGINE
COOLS DOWN.1. Vacuum created in cooling
system on engine cool-down is not
being relieved through coolant
recovery system.1. (a) Pressure cap relief valve
stuck. (Refer to 7 - COOLING/
ENGINE/RADIATOR PRESSURE
CAP - DIAGNOSIS AND TESTING)
Replace as necessary.
(b) Hose between the radiator and
overflow container is plugged or
pinched. Clean and repair as
necessary.
(c) Vent at coolant reserve/overflow
container is plugged. Clean vent
and repair as necessary.
(d) Reserve/overflow container is
internally blocked. Clean and repair
as necessary.
INADEQUATE AIR CONDITIONER
PERFORMANCE (COOLING
SYSTEM SUSPECTED).1. Radiator and/or A/C condenser is
restricted, obstructed, or dirty
(insects, leaves, etc.).1. Remove restriction and/or clean
as necessary.
2. Electrical radiator fan not
operating when A/C is operated.2. For test procedure (Refer to
appropriate Diagnostic Information).
Repair as necessary.
3. Engine is overheating (heat may
be transferred from radiator to A/C
condenser). High underhood
temperatures due to engine
overheating may also transfer heat
to A/C components.3. Correct overheating condition.
4. All models are equipped with air
seals at the radiator and/or A/C
condenser. If these seals are
missing or damaged, not enough
air flow will be pulled through the
radiator and A/C condenser.4. Check for missing or damaged air
seals and repair as necessary.
INADEQUATE HEATER
PERFORMANCE.1. Check for a Diagnostic trouble
code (DTC).1. For procedures, (Refer to
appropriate Diagnostic Information).
Repair as necessary.
2. Coolant level low. 2. (Refer to 7 - COOLING -
STANDARD PROCEDURE) Repair
as necessary.
RSENGINE7-15
ENGINE (Continued)
ProCarManuals.com
CONDITION POSSIBLE CAUSES CORRECTION
3. Obstructions in heater hose
fitting at engine or at heater core.3. Remove heater hoses at both
ends and check for obstructions.
Repair as necessary.
4. Heater hose kinked. 4. Locate kinked area and repair as
necessary.
5. Water pump is not pumping
coolant to heater core.5. When the engine is fully warmed
up, both heater hoses should be hot
to the touch. If only one of the
hoses is hot, the water pump may
not be operating correctly. Replace
components as necessary.
6. Air trapped in heater core. 6. (Refer to 7 - COOLING -
DIAGNOSIS AND TESTING -
COOLING SYSTEM DEAERATION)
HEAT ODOR 1. Various heat shields are used at
certain driveline components. One
or more of these shields may be
missing.1. Locate missing shields and
replace or repair as necessary.
2. Temperature gauge reading
above the normal range.2. Refer to Gauge Is Reading High
in Temperature Gauge Indicatication
Diagnosis Chart.
3. Radiator fan operating
incorrectly.3. (Refer to 7 - COOLING/ENGINE/
RADIATOR FAN - OPERATION)
Repair as necessary.
4. Undercoating been applied to an
unnecessary component.4. Clean undercoating as necessary.
5. Engine may be running rich,
causing the catalytic converter to
overheat5. (Refer to Appropriate Diagnostic
Information) Repair as necessary.
POOR DRIVEABILITY
(THERMOSTAT POSSIBLY STUCK
OPEN). GAUGE MAY BE READING
LOW.1. The engine thermostat must be
operating correctly for proper
driveability, clean vehicle emissions,
and the prevention of sludge
buildup in the engine oil. Check for
a diagnostic trouble code.1. (Refer to Appropriate Diagnostic
Information) Replace thermostat, if
necessary.
STEAM IS COMING FROM FRONT
OF VEHICLE NEAR GRILL AREA
WHEN WEATHER IS WET,
ENGINE WARMED UP AND
RUNNING WITH VEHICLE
STATIONARY, OR JUST SHUT
OFF. TEMPERATURE GAUGE IS
NORMAL.1. During wet weather, moisture
(snow, ice, rain, or condensation)
on the radiator will evaporate when
the thermostat opens. The
thermostat opening allows heated
coolant into the radiator. When the
moisture contacts the hot radiator,
steam may be emitted. This usually
occurs in cold weather with no fan
or air flow to blow it away.1. Occasional steam emitting from
this area is normal. No repair is
necessary.
7 - 16 ENGINERS
ENGINE (Continued)
ProCarManuals.com
CONDITION POSSIBLE CAUSES CORRECTION
COOLANT COLOR 1. Coolant color is not necessarily
an indication of adequate corrosion
or temperature protection. Do not
rely on coolant color for determining
condition of coolant.1. Check the freeze point of the
coolant. (Refer to 7 - COOLING/
ENGINE/COOLANT - DIAGNOSIS
AND TESTING) Adjust the ethylene
glycol-to-water ratio as necessary.
COOLANT LEVEL CHANGES IN
COOLANT BOTTLE.
TEMPERATURE GAUGE IS IN
NORMAL RANGE.1. Level changes are to be
expected as coolant volume
fluctuates with engine temperature.
The coolant level will also drop as
the system removes air from a
recent filling.1. A normal condition. No repair is
necessary.
Refer to (Fig. 1) when using the TEMPERATURE
GAUGE INDICATION DIAGNOSIS CHART.
TEMPERATURE GAUGE INDICATION DIAGNOSIS CHART
CONDITION POSSIBLE CAUSES CORRECTION
TEMPERATURE GAUGE READING
IS INCONSISTENT (FLUCTUATES,
CYCLES OR IS ERRATIC).1. Normal reaction to fan and/or
thermostat cycle (Fig. 1 ),
Examples B and C. During cold
weather operation with the heater
blower in the high position, the
gauge reading may drop slightly
(Fig. 1 ), Example D. Fluctuation is
also influenced by outside
temperature and heavy loads (Fig.
1 ), Example E.1. A normal condition. No correction
is necessary.
2. Gauge reading rises when
vehicle is brought to a stop after
heavy use (engine still running)
(Fig. 1 ), Example F.2. A normal condition. No correction
is necessary. Gauge reading should
return to normal range (Fig. 1 ),
Example A, after vehicle is driven.
3. Gauge reading high after
restarting a warmed-up (hot)
engine.3. A normal condition. No correction
is necessary. The gauge should
return to normal range (Fig. 1 ),
Example A, after a few minutes of
engine operation.
4. Temperature gauge or engine
coolant temperature sensor
defective or shorted. Also, corroded
or loose wiring in the electrical
circuit.4. Check operation of gauge or
engine coolant temperature sensor
and repair, if necessary.
RSENGINE7-17
ENGINE (Continued)
ProCarManuals.com
COOLANT
DESCRIPTION - ENGINE COOLANT
WARNING: ANTIFREEZE IS AN ETHYLENE GLYCOL
BASE COOLANT AND IS HARMFUL IF SWAL-
LOWED OR INHALED. IF SWALLOWED, DRINK
TWO GLASSES OF WATER AND INDUCE VOMIT-
ING. IF INHALED, MOVE TO FRESH AIR AREA.
SEEK MEDICAL ATTENTION IMMEDIATELY. DO NOT
STORE IN OPEN OR UNMARKED CONTAINERS.
WASH SKIN AND CLOTHING THOROUGHLY AFTER
COMING IN CONTACT WITH ETHYLENE GLYCOL.
KEEP OUT OF REACH OF CHILDREN. DISPOSE OF
GLYCOL BASE COOLANT PROPERLY, CONTACT
YOUR DEALER OR GOVERNMENT AGENCY FOR
LOCATION OF COLLECTION CENTER IN YOUR
AREA. DO NOT OPEN A COOLING SYSTEM WHEN
THE ENGINE IS AT OPERATING TEMPERATURE OR
HOT UNDER PRESSURE, PERSONAL INJURY CAN
RESULT. AVOID RADIATOR COOLING FAN WHEN
ENGINE COMPARTMENT RELATED SERVICE IS
PERFORMED, PERSONAL INJURY CAN RESULT.
CAUTION: Use of Propylene Glycol based coolants
is not recommended, as they provide less freeze
protection and less boiling protection.
The cooling system is designed around the coolant.
The coolant must accept heat from engine metal, in
the cylinder head area near the exhaust valves and
engine block. Then coolant carries the heat to the
radiator where the tube/fin radiator can transfer the
heat to the air.
The use of aluminum cylinder blocks, cylinder
heads, and water pumps requires special corrosion
protection. MopartAntifreeze/Coolant, 5
Year/100,000 Mile Formula (MS-9769), or the equiva-
lent ethylene glycol base coolant with hybrid organic
corrosion inhibitors (called HOAT, for Hybrid Organic
Additive Technology) is recommended. This coolant
offers the best engine cooling without corrosion when
mixed with 50% Ethylene Glycol and 50% distilled
water to obtain a freeze point of -37ÉC (-35ÉF). If it
loses color or becomes contaminated, drain, flush,
and replace with fresh properly mixed coolant solu-
tion.
The green coolantMUST NOT BE MIXEDwith
the orange or magenta coolants. When replacing cool-
ant the complete system flush must be performed
before using the replacement coolant.
CAUTION: MoparTAntifreeze/Coolant, 5
Year/100,000 Mile Formula (MS-9769) may not be
mixed with any other type of antifreeze. Doing so
will reduce the corrosion protection and may resultin premature water pump seal failure. If non-HOAT
coolant is introduced into the cooling system in an
emergency, it should be replaced with the specified
coolant as soon as possible.DIAGNOSIS AND TESTING - COOLANT
CONCENTRATION TESTING
Coolant concentration should be checked when any
additional coolant was added to system or after a
coolant drain, flush and refill. The coolant mixture
offers optimum engine cooling and protection against
corrosion when mixed to a freeze point of -37ÉC
(-34ÉF) to -46ÉC (-50ÉF). The use of a hydrometer or a
refractometer can be used to test coolant concentra-
tion.
A hydrometer will test the amount of glycol in a
mixture by measuring the specific gravity of the mix-
ture. The higher the concentration of ethylene glycol,
the larger the number of balls that will float, and
higher the freeze protection (up to a maximum of
60% by volume glycol).
A refractometer (Special Tool 8286)(Refer to 7 -
COOLING - SPECIAL TOOLS) will test the amount
of glycol in a coolant mixture by measuring the
amount a beam of light bends as it passes through
the fluid.
Some coolant manufactures use other types of gly-
cols into their coolant formulations. Propylene glycol
is the most common new coolant. However, propylene
glycol based coolants do not provide the same freez-
ing protection and corrosion protection and is not rec-
ommended.
CAUTION: Do not mix types of coolantÐcorrosion
protection will be severely reduced.
STANDARD PROCEDURE - COOLANT SERVICE
For engine coolant recommended service schedule,
(Refer to LUBRICATION & MAINTENANCE/MAIN-
TENANCE SCHEDULES - DESCRIPTION).
COOLANT RECOVERY
CONTAINER
DESCRIPTION
The coolant recovery/reserve system container is
mounted in the engine compartment (Fig. 2). The
container is made of plastic.
OPERATION
The coolant recovery system works with the radia-
tor pressure cap to use thermal expansion and con-
traction of the coolant to keep the coolant free of
trapped air. Provides a convenient and safe method
RSENGINE7-19
ProCarManuals.com