2003 CHRYSLER CARAVAN radiator

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
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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)
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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)
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CLEANING
Drain cooling system and refill with clean water.
Refer to drain and fill procedures in this section. Run
engine with radiator cap installed until upper radia-
tor hose is hot. Stop engine and drain water from
system. If water is dirty; fill, run, and drain system
again, until water runs clear. Refill cooling system
with a 50/50 mixture of the recommended ethylene
glycol and distilled water (Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES - DESCRIPTION).
INSPECTION
After performing a cleaning/flush procedure,
inspect all hoses, clamps and connections for deterio-
ration and leaks. Inspect radiator and heater core for
leaks.
Fig. 1 Temperature Gauge Indications
7 - 18 ENGINERS
ENGINE (Continued)
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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
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for checking coolant level and adjusting level at
atmospheric pressure without removing the radiator
pressure cap. It also provides some reserve coolant to
cover deaeration, evaporation, or boiling losses.
DIAGNOSIS AND TESTING - COOLANT
RECOVERY SYSTEM
The cooling system is closed and designed to main-
tain coolant level to the top of the radiator.
(1) With the engineoffand cooling systemnot
under pressure, drain several ounces of coolant from
the radiator draincock while observing the coolant
recovery container. Coolant level in the container
should drop.
(2) Remove the radiator pressure cap. The coolant
level should be full to the top radiator neck. If not,
and the coolant level in the container is at or above
the MIN mark, there is an air leak in the coolant
recovery system.
(3) Check hose and hose connections to the con-
tainer, radiator filler neck or the pressure cap seal to
the radiator filler neck for leaks.
REMOVAL
(1) Raise the vehicle on hoist.
(2) Remove the lower attaching screws (Fig. 2).
(3) Lower the vehicle.
(4) Remove the upper attaching screw (Fig. 2).
(5) Disconnect recovery hose from container (Fig.
2).
(6) Remove the recovery container.
INSTALLATION
(1) Connect the recovery hose to container (Fig. 2).
(2) Position the recovery container on the frame
rail (Fig. 2).
(3) Install the upper attaching screw and tighten
to 7 N´m (60 in. lbs.) (Fig. 2).
(4) Raise the vehicle on hoist.
(5) Install the lower attaching screws and tighten
to 8.5 N´m (75 in. lbs.) (Fig. 2).
(6) Lower the vehicle.
(7) Add coolant to container as necessary. (Refer to
7 - COOLING - STANDARD PROCEDURE)
ENGINE BLOCK HEATER
DESCRIPTION
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.
OPERATION
The block heater element is submerged in the cool-
ing system's coolant. When electrical power (110 volt
A.C.) is applied to the element, it creates heat. This
heat is transferred to the engine coolant. This pro-
vides easier engine starting and faster warm-up
when vehicle is operated in areas having extremely
low temperatures.
DIAGNOSIS AND TESTING - ENGINE BLOCK
HEATER TESTING
If unit does not operate, trouble can be in either
the power cord or the heater element. Test power
cord for continuity with a 110-volt voltmeter or 110-
volt test light; test heater element continuity with an
ohmmeter or 12-volt test light.
REMOVAL
(1) Drain coolant from radiator and cylinder block.
(Refer to 7 - COOLING - STANDARD PROCEDURE)
(2) Disconnect the power cord plug from heater.
(3) Loosen screw in center of heater. Remove the
heater assembly.
INSTALLATION
(1) Clean block core hole and heater seat.
(2) Insert heater assembly with element loop posi-
tionedupward.
Fig. 2 Coolant Recovery Container
1 - UPPER BOLT ATTACHING TO BATTERY TRAY
2 - COOLANT RECOVERY CONTAINER
3 - UPPER BOLT
4 - HOSE
5 - LOWER BOLT (QTY. 2)
6 - LEFT SIDE FRAME RAIL
7 - 20 ENGINERS
COOLANT RECOVERY CONTAINER (Continued)
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(3) Remove ignition coil and bracket (Fig. 5).
(4) Disconnect coolant sensor electrical connector
(Fig. 6).
(5) Remove coolant sensor (Fig. 6).
INSTALLATION
(1) Install engine coolant temperature sensor (Fig.
6). Tighten sensor to 7 N´m (60 in. lbs.).
(2) Connect electrical connector to sensor (Fig. 6).
(3) Install ignition coil bracket (Fig. 5).
(4) Install ignition coil (Fig. 5).
(5) Install power steering reservoir (Fig. 4).
(6) Fill cooling system. (Refer to 7 - COOLING -
STANDARD PROCEDURE)
ENGINE COOLANT
THERMOSTAT
DESCRIPTION
The engine cooling thermostats are a wax pellet
driven, reverse poppet choke type. The thermostat is
mounted in a housing on the coolant outlet of the
engine (Fig. 8) or (Fig. 10).
OPERATION
The engine cooling thermostat is a wax pellet
driven, reverse poppet choke type. The thermostat is
designed to provide the fastest warm up possible by
preventing leakage through it and to guarantee a
minimum engine operating temperature of 88 to
93ÉC (192 to 199ÉF). The thermostat also will auto-
matically reach wide open so it will not restrict flow
to the radiator as temperature of the coolant rises in
hot weather to around 104ÉC (220ÉF). Above this
temperature the coolant temperature is controlled by
the radiator, fan, and ambient temperature, not the
thermostat.
The thermostat is operated by a wax filled con-
tainer (pellet) which is sealed. When heated coolant
reaches a predetermined temperature, the wax
expands enough to overcome the closing spring and
water pump pressure, which forces the valve to open.
Fig. 5 Fuel Rail, Ignition Coil and Bracket
1 - FUEL RAIL
2 - BOLT - FUEL RAIL
3 - NUT - IGNITION COIL
4 - BOLT - IGNITION COIL
5 - IGNITION COIL
6 - BRACKET - IGNITION COIL
7 - STUD - IGNITION COIL
8 - SEPARATOR - SPARK PLUG CABLE
9 - BRACKET - SPARK PLUG CABLE SEPARATOR
10 - BOLT - SEPARATOR BRACKET
11 - BRACKET - SPARK PLUG CABLE SEPARATOR
Fig. 6 Engine Coolant Temperature Sensor
1 - ENGINE COOLANT TEMPERATURE SENSOR
2 - CONNECTOR - ENGINE COOLANT SENSOR
3 - FITTING - HEATER SUPPLY
7 - 22 ENGINERS
ENGINE COOLANT TEMPERATURE SENSOR - 3.3/3.8L (Continued)
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DIAGNOSIS AND TESTING - ENGINE COOLANT
THERMOSTAT
The thermostat is operated by a wax filled cham-
ber (pellet) which is sealed. When heated coolant
reaches a predetermined temperature the wax pellet
expands enough to overcome the closing spring and
water pump pressure, which forces the valve to open.
Coolant leakage into the pellet will cause a thermo-
stat to fail open. Do not attempt to free up a thermo-
stat with a screwdriver.
Thermostat diagnostics is included in powertrain
control module's (PCM) programing for on-board
diagnosis. The malfunction indicator light (MIL) will
illuminate and a diagnostic trouble code (DTC) will
be set when an ªopen too soonº condition occurs. Do
not change a thermostat for lack of heater perfor-
mance or temperature gauge position, unless a DTC
is present. For other probable causes, (Refer to 7 -
COOLING/ENGINE - DIAGNOSIS AND TESTING).
Thermostat failing shut is the normal long term
mode of failure, and normally, only on high mileage
vehicles. The temperature gauge will indicate this
(Refer to 7 - COOLING/ENGINE - DIAGNOSIS AND
TESTING).
ENGINE COOLANT
THERMOSTAT - 2.4L
REMOVAL
(1) Drain cooling system below the thermostat
level. (Refer to 7 - COOLING - STANDARD PROCE-
DURE)
(2) Remove radiator upper hose from the coolant
outlet housing (Fig. 7).
(3) Remove coolant outlet housing bolts and hous-
ing (Fig. 8).
(4) Remove thermostat. Discard gasket and clean
both gasket sealing surfaces.
INSTALLATION
(1) Place a new gasket (dipped in clean water) on
the coolant outlet connector surface. Position thermo-
stat with air bleed at the 12 o'clock position in ther-
mostat housing (Fig. 8).
(2) Position the coolant outlet connector and gas-
ket over the thermostat, making sure thermostat is
seated in the thermostat housing.
(3) Position outlet connector to thermostat housing
and install bolts (Fig. 8). Tighten bolts to 28 N´m
(250 in. lbs.).
(4) Install the radiator upper hose to coolant outlet
housing (Fig. 7).
(5) Refill the cooling system. (Refer to 7 - COOL-
ING - STANDARD PROCEDURE)
ENGINE COOLANT
THERMOSTAT - 3.3/3.8L
REMOVAL
(1) Drain cooling system down below the thermo-
stat level. (Refer to 7 - COOLING - STANDARD
PROCEDURE)
(2) Remove radiator upper hose from coolant outlet
connector (Fig. 9).
Fig. 7 RADIATOR HOSES TO ENGINE - 2.4L
1 - UPPER HOSE
2 - LOWER HOSE
Fig. 8 Thermostat and Outlet Connector - 2.4L
Engine
1 - THERMOSTAT
2 - GASKET
3 - COOLANT OUTLET CONNECTOR
4 - BOLT
RSENGINE7-23
ENGINE COOLANT THERMOSTAT (Continued)
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