2002 CHRYSLER CARAVAN radiator cap

CONDITION POSSIBLE CAUSES CORRECTION
5. Coolant level low in the coolant
tank (air will build up in the cooling
system causing the thermostat to
open late).5. Check and correct coolant
leaks.
6. Cylinder head gasket leaking
allowing exhaust gases to enter the
cooling system causing the
thermostat to open late.6. (a) Check for cylinder head
gasket leaks with a
commercially available leak
tester. (b) Check for coolant in
engine oil. Inspect for white
steam emitting from exhaust
system. Repair as necessary.
7. Water pump impeller loose on
shaft.7. Check water pump and
replace as necessary.
8. Loose accessory drive belt (water
pump slipping).8. Check and correct as
necessary.
9. Air leak on the suction side of the
water pump allowing air to build up
in the cooling system causing the
thermostat to open late.9. Locate leak and repair as
necessary.
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 TANK1. Pressure relief valve in pressure/
vent cap is defective.1. Check condition of
pressure/vent cap and cap
seals.
2. Head gasket leak or cracked
cylinder head.2. Repair as necessary.
COOLANT LOSS TO THE
GROUND WITHOUT
PRESSURE CAP
BLOWOFF. GAUGE IS
READING HIGH OR HOT1. Coolant leaks in radiator, cooling
system hoses, water pump, or
engine.1. Pressure test cooling system
and repair as necessary.
HOSE OR HOSES
COLLAPSE WHEN
ENGINE IS COOLING1. Vacuum created in cooling system
on engine cool-down is not being
relieved through pressure/vent cap.1. Cap relief valve stuck.
Replace if necessary.
NOISY FAN 1. Cooling fan blades loose. 1. Replace cooling fan
assembly.
2. Cooling fan blades striking a
surrounding object.2. Locate point of fan blade
contact and repair as
necessary.
3. Air obstructions at radiator or A/C
condensor.3. Remove obstructions or
clean debris from radiator or
A/C condensor.
7a - 4 COOLING 2.5L TURBO DIESELRG
COOLING 2.5L TURBO DIESEL (Continued)
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CONDITION POSSIBLE CAUSES CORRECTION
4. Has undercoating been applied to
any unnecessary components?4. Clean undercoating as
necessary.
STEAM IS COMING FROM
FRONT OF VEHICLE
NEAR GRILL AREA WHEN
WEATHER IS WET,
ENGINE IS WARMED UP
AND RUNNING, AND
VEHICLE IS STATIONARY.
TEMPERATURE GAUGE
IS IN NORMAL RANGE1. During wet weather, moisture
(snow, ice, or rain condensation) on
the radiator will evaporate when the
thermostat opens. This opening
allows heated water into the radiator.
When the moisture contacts the hot
radiator, steam may be emitted. This
usually occurs in cold weather with
no fan or airflow to blow it away.1. Occasional steam emitting
from this area is normal. No
repair is necessary.
COOLANT ODOR 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. Refer to Coolant in this group
for antifreeze tests. Adjust
antifreeze-to-water ratio as
necessary.
COOLANT LEVEL
CHANGES IN COOLANT
TANK. TEMPERATURE
GAUGE IS IN NORMAL
RANGE1. Level changes are to be expected
as coolant volume fluctuates with
engine temperature. If the level in
the tank was between the HOT and
COLD marks at normal engine
operating temperature, the level
should return to within that range
after operation at elevated
temperatures.1. This a normal condition. No
repair necessary.
DIAGNOSIS AND TESTING - COOLING SYSTEM
LEAK TEST
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.
With engine not running, remove pressure/vent cap
from the coolant recovery pressure container and
wipe the filler neck sealing seat clean. The coolant
recovery pressure container should be full.
Attach the Cooling System Tester 7700 or equiva-
lent to the radiator, as shown in (Fig. 1) and apply
104 kPa (15 psi) pressure. If the pressure drops more
than 13.8 kPa (2 psi) in 2 minutes, inspect all points
for external leaks.
All radiator and heater hoses should be shaken
while at 104 kPa (15 psi), since some leaks occur only
while driving due to engine movement.
If there are no external leaks, after the gauge dial
shows a drop in pressure, detach the tester. Startengine and run until the thermostat opens, allowing
the coolant to expand. Reattach the cooling system
tester. If the needle on the dial fluctuates it indicates
a combustion leak, usually a head gasket leak.
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, raise
the engine rpm a few times. If an abnormal amount
of coolant or steam emits from the tailpipe, 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.
7a - 6 COOLING 2.5L TURBO DIESELRG
COOLING 2.5L TURBO DIESEL (Continued)
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DIAGNOSIS AND TESTING - COOLING SYSTEM
FLOW CHECK
To determine whether coolant is flowing through
the cooling system, use the following procedures:
(1) If engine is cold, idle engine until normal oper-
ating temperature is reached. Then feel the upper
radiator hose. If it is hot, coolant is circulating.
WARNING: DO NOT REMOVE THE COOLING SYS-
TEM PRESSURE CAP WITH THE SYSTEM HOT AND
UNDER PRESSURE BECAUSE SERIOUS BURNS
FROM COOLANT CAN OCCUR.(2) Remove pressure/vent cap when engine is cold,
idle engine until thermostat opens, you should
observe coolant flow while looking down in the cool-
ant recovery pressure container. Once flow is
detected install the pressure/vent cap.
DIAGNOSIS AND TESTING - COOLING SYSTEM
AERATION
Low coolant level in a cross flow radiator will
equalize in both tanks with engine off. With engine
at running and at operating temperature, the high
pressure inlet tank runs full and the low pressure
outlet tank drops, resulting in cooling system aera-
tion. Aeration will draw air into the water pump
resulting in the following:
²High reading shown on the temperature gauge.
²Loss of coolant flow through the heater core.
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.
CLEANING
Drain cooling system and refill with clean water.
Refer to procedures in this section. Run engine with
pressure/vent 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.
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 PRESSURE TESTING COOLING SYSTEM
1 - COOLING SYSTEM PRESSURE TESTER
2 - COOLANT RECOVERY PRESSURE CONTAINER
RGCOOLING 2.5L TURBO DIESEL7a-7
COOLING 2.5L TURBO DIESEL (Continued)
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ENGINE
TABLE OF CONTENTS
page page
COOLANT
DESCRIPTION.........................15
DIAGNOSIS AND TESTING - COOLANT
CONCENTRATION TESTING.............15
STANDARD PROCEDURE
STANDARD PROCEDURE - COOLANT
SERVICE............................16
STANDARD PROCEDURE - ADDING
ADDITIONAL COOLANT.................16
STANDARD PROCEDURE - COOLANT
LEVEL CHECK........................16
STANDARD PROCEDURE - COOLING
SYSTEM FILLING.....................16
STANDARD PROCEDURE - COOLING
SYSTEM DRAINING....................17
COOLANT RECOVERY PRESS CONTAINER
DESCRIPTION.........................17
OPERATION...........................17
REMOVAL.............................18
INSTALLATION.........................18
ENGINE COOLANT TEMP SENSOR
DESCRIPTION.........................19
OPERATION...........................19
REMOVAL.............................19
INSTALLATION.........................19
ENGINE COOLANT THERMOSTAT
DESCRIPTION.........................20
OPERATION...........................20
REMOVAL.............................20
INSTALLATION.........................20
RADIATOR
DESCRIPTION.........................21
OPERATION...........................21
REMOVAL.............................21
INSTALLATION.........................22
RADIATOR DRAINCOCK
REMOVAL.............................22
INSTALLATION.........................22
WATER PUMP
DESCRIPTION.........................23OPERATION...........................23
REMOVAL
REMOVAL - WATER PUMP..............23
REMOVAL - WATER PUMP HOUSING......23
CLEANING............................23
INSTALLATION
INSTALLATION - WATER PUMP..........23
INSTALLATION - WATER PUMP HOUSING . . 24
RADIATOR PRESSURE CAP
DESCRIPTION.........................25
OPERATION...........................25
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - COOLING
SYSTEM PRESSURE CAP...............25
DIAGNOSIS AND TESTING - PRESSURE
RELIEF TEST........................26
CLEANING............................26
INSPECTION..........................26
RADIATOR FAN
DESCRIPTION.........................26
OPERATION...........................27
DIAGNOSIS AND TESTING - RADIATOR FAN
MOTOR .............................27
REMOVAL.............................28
INSTALLATION.........................28
HOSE CLAMPS
DESCRIPTION - HOSE CLAMPS...........28
OPERATION - HOSE CLAMPS.............28
RADIATOR FAN RELAY
DESCRIPTION.........................29
OPERATION...........................29
COOLANT SYSTEM HOSES
REMOVAL
REMOVAL - UPPER RADIATOR HOSE.....29
REMOVAL - LOWER RADIATOR HOSE.....29
REMOVAL - COOLANT BYPASS HOSE.....30
INSTALLATION
INSTALLATION - UPPER RADIATOR HOSE . . 30
INSTALLATION - LOWER RADIATOR HOSE . 30
INSTALLATION - COOLANT BYPASS HOSE . 30
7a - 14 ENGINERG
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(5) Continue filling coolant recovery pressure con-
tainer until level reaches the full line.
(6) Without installing the pressure/vent cap, start
and run engine at idle for a couple minutes.
(7) Recheck coolant level and fill as necessary.
(8) Install pressure/vent cap and drive vehicle for
approx. 10 km to reach normal operating tempera-
tures.
(9) Allow vehicle to cool. Check and fill coolant as
needed.
STANDARD PROCEDURE - COOLING SYSTEM
DRAINING
WARNING: DO NOT REMOVE OR LOOSEN THE
COOLANT PRESSURE/VENT CAP, CYLINDER
BLOCK DRAIN PLUGS, OR THE DRAINCOCK WHEN
THE SYSTEM IS HOT AND UNDER PRESSURE
BECAUSE SERIOUS BURNS FROM THE COOLANT
CAN OCCUR.(1)Without removing pressure/vent cap and
with system not under pressure, open the drain-
cock. The draincock is located on the lower right side
of radiator (Fig. 3).
(2) After the coolant recovery pressure container is
empty, then remove coolant pressure/vent cap.
COOLANT RECOVERY PRESS
CONTAINER
DESCRIPTION
The coolant recovery pressure container is
mounted in the engine compartment next to the bat-
tery. The coolant recovery pressure container is made
of plastic (Fig. 4).
OPERATION
The coolant recovery pressure container works
with the pressure/vent cap to use thermal expansion
and contraction of the coolant to keep the coolant
free of trapped air. Provides a convenient and safe
method for checking coolant level and adjusting level
at atmospheric pressure without removing the pres-
sure/vent cap. It also provides some reserve coolant
to cover deaeration, evaporation, or boiling losses.
Fig. 2 COOLANT RECOVERY PRESSURE
CONTAINER LOCATION
1 - PRESSURE/VENT CAP
2 - BRAKE MASTER CYLINDER
3 - BATTERY
4 - BATTERY SHIELD
5 - COOLANT RECOVERY PRESSURE CONTAINER RETAING
CLIP
6 - ENGINE COVER
7 - COOLANT RECOVERY PRESSURE CONTAINER
Fig. 3 DRAINCOCK LOCATION
1 - RADIATOR
2 - DRAINCOCK
3 - LOWER RADIATOR SUPPORT
4 - ELECTRIC COOLING FAN
RGENGINE7a-17
COOLANT (Continued)
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ENGINE COOLANT TEMP
SENSOR
DESCRIPTION
The engine coolant temperature sensor threads
into a coolant passage in the cylinder head (Fig. 7).
New sensors have sealant applied to the threads.
OPERATION
The coolant temperature (ECT) sensor is a nega-
tive temperature coefficient (NTC) thermistor (resis-
tance varies inversley with temperature). This means
at cold tempertures its resistance is high so the volt-
age signal will be high. As coolant temperture
increases, resistance decreases and the signal voltage
will be low. This allows the sensor to provide an ana-
log voltage signal to the ECM.
REMOVAL
WARNING: DO NOT REMOVE OR LOOSEN THE
COOLANT PRESSURE/VENT CAP, CYLINDER
BLOCK DRAIN PLUGS, OR THE DRAINCOCK WHEN
THE SYSTEM IS HOT AND UNDER PRESSURE
BECAUSE SERIOUS BURNS FROM THE COOLANT
CAN OCCUR.(1) Drain the cooling system. (Refer to 7 - COOL-
ING/ENGINE/COOLANT - STANDARD PROCE-
DURE)
(2) Disconnect coolant temperature sensor electri-
cal connector (Fig. 8).
(3) Remove coolant temperature sensor from cylin-
der head (Fig. 8).
INSTALLATION
(1) Install coolant temperature sensor in cylinder
head (Fig. 8).
(2) Connect coolant temperature sensor electrical
connector (Fig. 8).
(3) Refill the cooling system. (Refer to 7 - COOL-
ING/ENGINE/COOLANT - STANDARD PROCE-
DURE)
(4) Connect the negative battery cable.
Fig. 6 COOLANT RECOVERY PRESSURE
CONTAINER
1 - COOLANT RECOVERY PRESSURE CONTAINER
2 - COOLANT BYPASS HOSE
3 - OUTLET HOSE
4 - PRESSURE/VENT CAP
Fig. 7 COOLANT TEMPERATURE SENSOR
LOCATION
1 - EGR SOLENOID
2 - UPPER RADIATOR HOSE
3 - COOLANT TEMPERATURE SENSOR
4 - INTAKE MANIFOLD INLET
5 - INTAKE MANIFOLD/CYLINDER HEAD COVER
RGENGINE7a-19
COOLANT RECOVERY PRESS CONTAINER (Continued)
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(3) Install front wiper unit (Refer to 8 - ELECTRI-
CAL/WIPERS/WASHERS/WIPER MODULE -
INSTALLATION).
(4) Refill cooling system (Refer to 7 - COOLING/
ENGINE/COOLANT - STANDARD PROCEDURE).
(5) Connect negative battery cable.
RADIATOR
DESCRIPTION
The radiator is a cross-flow type (horizontal tubes)
with design features that provide greater strength
along with sufficient heat transfer capabilities to
keep the engine satisfactorily cooled. The radiator
has plastic side tanks and aluminum cooling tubes.
OPERATION
The radiator functions as a heat exchanger, using
air flow across the exterior of the radiator tubes. This
heat is then transferred from the coolant and into
the passing air.
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove radiator upper crossmember support.
(Refer to 23 - BODY/EXTERIOR/GRILLE OPENING
REINFORCEMENT - REMOVAL)
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.
(3) Drain the cooling system (Refer to 7 - COOL-
ING/ENGINE/COOLANT - STANDARD PROCE-
DURE).
(4) Remove the radiator fans. (Refer to 7 - COOL-
ING/ENGINE/RADIATOR FAN - REMOVAL)
(5) Disconnect coolant bypass hose (Fig. 11).
(6) Disconnect upper and lower hoses from the
radiator (Fig. 11).
(7) Remove the A/C condenser side brackets to
radiator attaching screws (Fig. 12). Separate the con-
denser from the radiator by lifting upward to disen-
gage from lower mounts (Fig. 12). Allow the
condenser to rest in front of radiator.
Fig. 10 THERMOSTAT HOUSING ASSEMBLY
1 - THERMOSTAT HOUSING GASKET
2 - THERMOSTAT HOUSING
3 - RETAINING BOLTS
4 - CYLINDER HEAD
5 - CYLINDER HEAD COVER/INTAKE MANIFOLD
Fig. 11 UPPER AND LOWER RADIATOR HOSES
1 - COOLANT BYPASS HOSE
2 - RADIATOR ASSEMBLY
3 - UPPER RADIATOR HOSE
4 - COOLING FAN
5 - LOWER RADIATOR HOSE
6 - CHARGE AIR COOLER
7 - RADIATOR BRACKET
RGENGINE7a-21
ENGINE COOLANT THERMOSTAT (Continued)
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RADIATOR PRESSURE CAP
DESCRIPTION
The cooling system pressure cap is located on the
radiator. The cap construction includes; stainless
steel swivel top, rubber seals, and retainer, main
spring, and a spring loaded valve (Fig. 19).
OPERATION
The cooling system is equipped with a pressure cap
that releases excessive pressure; maintaining a range
of 97-124 kPa (14-18 psi).
The cooling system will operate at higher than
atmospheric pressure. The higher pressure raises the
coolant boiling point thus, allowing increased radia-
tor cooling capacity.
There is also a vent valve in the center of the cap.
This valve also opens when coolant is cooling and
contracting, allowing the coolant to return to cooling
system from coolant reserve system tank by vacuum
through a connecting hose.If valve is stuck shut,
or the coolant recovery hose is pinched, the
radiator hoses will be collapsed on cool down.
Clean the vent valve (Fig. 19) and inspect cool-
ant recovery hose routing, to ensure proper
sealing when boiling point is reached.
The gasket in the cap seals the filler neck, so that
vacuum can be maintained, allowing coolant to be
drawn back into the radiator from the reserve tank.
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.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - COOLING SYSTEM
PRESSURE CAP
Dip the pressure cap in water. Clean any deposits
off the vent valve or its seat and apply cap to end of
the Pressure Cap Test Adaptor that is included with
the Cooling System Tester 7700. 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 the pressure cap.
CAUTION: The Cooling System Tester Tool is very
sensitive to small air leaks that will not cause cool-
ing system problems. A pressure cap that does not
have a history 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.
If the pressure cap tests properly while positioned
on Cooling System Tester (Fig. 20), but will not hold
pressure or vacuum when positioned on the filler
neck. Inspect the filler neck and cap top gasket for
irregularities that may prevent the cap from sealing
properly.
Fig. 19 Cooling System Pressure Cap Filler Neck
1 - OVERFLOW NIPPLE
2 - MAIN SPRING
3 - GASKET RETAINER
4 - STAINLESS-STEEL SWIVEL TOP
5 - RUBBER SEALS
6 - VENT VALVE
7 - PRESSURE BOTTLE
8 - FILLER NECK
Fig. 20 Testing Cooling System Pressure Cap
1 - PRESSURE CAP
2 - PRESSURE TESTER
RGENGINE7a-25
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