cooling CHRYSLER CARAVAN 2002 Workshop Manual

COOLING SYSTEM DIAGNOSIS-DIESEL ENGINE
CONDITION POSSIBLE CAUSES CORRECTION
TEMPERATURE GAUGE
READS LOW1. Diesel engines, due to their
inherent effiency are slower to warm
up than gasoline powered engines,
and will operate at lower
temperatures when the vehicle is
unloaded.1. The low gauge reading may
be normal. Refer to thermostats
in the manual text for
information. See Thermostat
Diagnosis-Diesel Engine.
2. Is the temperature gauge
connected to the temperature gauge
coolant sensor on the engine?2. Check, the engine
temperature sensor connector
in the engine compartment.
3. Is the temperature gauge
operating OK?3. Check gauge operation.
Repair as necessary.
4. Coolant level low in cold ambient
temperatures accompanied with poor
heater performance.4. Check coolant level in the
coolant tank. Inspect system for
leaks. Repair leaks as
necessary. Refer to the Coolant
section for WARNINGS and
precautions before removing
the pressure cap.
5. Improper operation of internal
heater doors or heater controls.5. Inspect heater and repair as
necessary. Refer to Heating
and Air Conditioning for
procedures.
TEMPERATURE GAUGE
READS HIGH. COOLANT
MAY OR MAY NOT BE
LOST OR LEAKING FROM
COOLING SYSTEM1. Trailer is being towed, a steep hill
is being climbed, vehicle is operated
in slow moving traffic, or engine is
being idled with very high ambient
(outside) temperature and the air
conditioning is on. Higher altitudes
could aggravate these conditions.1. This may be a temporary
condition and repair is not
necessary. Turn off the air
conditioning and attempt to
drive the vehicle without any of
the previous conditions.
Observe the temperature
gauge. The gauge should return
to the normal range. If the
gauge does not return to
normal range, determine the
cause for the overheating and
repair.
2. Temperature gauge reading
incorrectly.2. Check gauge. Refer to I/P
group.
3. Coolant low in coolant tank and
radiator.3. Check for coolant leaks and
repair as necessary.
4. Pressure cap not installed tightly.
If cap is loose, boiling point of
coolant will be lowered.4. Tighten cap.
5. Poor seals at pressure/vent cap. 5. (a) Check condition of cap
and cap seals. (b) Check
condition of coolant tank filler
neck. Make sure it does not
leak pressure.
7a - 2 COOLING 2.5L TURBO DIESELRG
COOLING 2.5L TURBO DIESEL (Continued)
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CONDITION POSSIBLE CAUSES CORRECTION
6. Freeze point of antifreeze not
correct. Mixture may be too rich.6. Check antifreeze. Adjust
antifreeze-to-water ratio as
required.
7. Coolant not flowing through
system.7. Check for coolant flow in
coolant tank with engine warm
and thermostat open. Coolant
should be observed flowing
through the tank. If flow is not
observed, determine reason for
lack of flow and repair as
necessary.
8. Radiator or A/C condensor fins
are dirty or clogged.8. Clean debris from radiator or
A/C condensor
9. Radiator core is corroded or
plugged.9. Have radiator re-cored or
replaced.
10. Aftermarket A/C installed without
proper A/C condensor.10. Install proper A/C
condensor.
11. Dragging Brakes. 11. Check and correct as
necessary.
12. Non-factory bug screen is being
used reducing airflow.12. Only a factory screen
should be used.
13. Thermostat partially or
completely shut. This is more
prevalent on high mileage vehicles.13. Check thermostat and
replace if necessary.
14. Cylinder head gasket leaking. 14. Check cylinder head gasket
for leaks.
15. Heater core leaking. 15. Check heater cor for leaks.
Repair as necessary.
TEMPERATURE GAUGE
READING IS
INCONSISTENT
(FLUCTUATES, CYCLES
OR IS ERRATIC)1. During cold weather operation,
with the heater blower in the high
position, the gauge reading may
drop slightly. Fluctuation is also
influenced by loads, outside
temperature and extended idle time
with diesel engines.1. A normal condition. No
correction is necessary.
2. Temperature gauge or engine
mounted gauge sensor defective or
shorted. Also, corroded or loose
wiring in this circuit.2. Check operation of gauge
and repair as necessary.
3. Gauge reading rises when vehicle
is brought to a stop after heavy use
(engine still running).3. A normal condition. No
correction needed. Gauge
should return to normal range
after vehicle is driven.
4. Gauge reading high after starting
a warm-iup (hot) engine.4. A normal condition. No
correction needed. Gauge
should return to normal after a
few minutes of engine
operation.
RGCOOLING 2.5L TURBO DIESEL7a-3
COOLING 2.5L TURBO DIESEL (Continued)
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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
INADEQUATE AIR
CONDITIONER
PERFORMANCE
(COOLING SYSTEM
SUSPECTED)1. Radiator and/or A/C condensor is
restricted, obstructed or dirty
(insects, leaves, etc.)1. Remove restriction or clean
debris from radiator or A/C
condensor.
2. Engine is overheating (heat may
be transferred from radiator to A/C
condensor. High underhood
temperatures due to engine
overheating may also transfer heat
to A/C condensor).2. Correct overheating
condition.
3. The cooling system is equipped
with air seals at the radiator and/or
A/C condensor. If these seals are
missing or damaged, not enough air
flow will be pulled through the
radiator and A/C condensor.3. Check for missing or
damaged air seals. Repair as
necessary.
INADEQUATE HEATER
PERFORMANCE. MAY BE
ACCOMPANIED BY LOW
GAUGE READING1. Diesel engines, due to their
inherent efficiency are slower to
warm up than gasoline powered
engines, and will operate at lower
temperatures when the vehicle is
unloaded.1. The lower gauge reading
may be normal.
2. Coolant level low. 2. Pressure test cooling system.
Repair leaks as necessary.
3. Obstruction in heater hose fitting
at engine.3. Remove heater hoses and
check for obstructions. Repair
as necessary.
4. Heater hose kinked. 4. Locate kinked area. Repair
as necessary.
5. Water pump is not pumping water
to heater core. 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.
The accessory drive belt may also
be slipping causing poor water pump
operation.5. Refer to water pumps in this
group. Repair as necessary. If a
slipping belt is detected, refer to
Engine Accessory Drive Belts in
this group. Repair as
necessary.
HEAT ODOR 1. Various heat shields are used at
certain drive line components. One
or more of these shields may be
missing.1. Locate missing shields.
Repair or replace as necessary.
2. Is temerature gauge reading
above the normal range?2. Refer to the previous
Temperature Gauge Reads
High in these Diagnostic
Charts. Repair as necessary.
3. Is the Cooling fan operating
correctly?3. Refer to Cooling System Fan
in this group for diagnosis.
Repair as necessary.
RGCOOLING 2.5L TURBO DIESEL7a-5
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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SPECIFICATIONS
SPECIFICATIONS - TORQUE
2.5L DIESEL - TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Water Pump Housing Nuts 24.4 18 215
Thermostat Housing Bolts 27.5 21 Ð
Accessory Drive Belt
Tensioner Bolt47.1 35 Ð
Accessory Drive Belt Idler
Bolt53 39 Ð
SPECIFICATIONS - COOLING SYSTEM
CAPACITY
SPECIFICATIONS
DESCRIPTION SPECIFICATION
Cooling System With
Auxiliary Heater16.6 Liters (17.5 qts.)
Cooling System With Out
Auxiliary Heater13.8 Liters (14.6 qts.)
7a - 8 COOLING 2.5L TURBO DIESELRG
COOLING 2.5L TURBO DIESEL (Continued)
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ACCESSORY DRIVE
TABLE OF CONTENTS
page page
ACCESSORY DRIVE
SPECIFICATIONS - ACCESSORY BELT
TENSION.............................9
BELT TENSIONER
REMOVAL.............................9
INSTALLATION..........................9
IDLER PULLEY
REMOVAL.............................10
INSTALLATION.........................10
DRIVE BELTS
DESCRIPTION
DESCRIPTION - ACCESSORY DRIVE BELT . 10DESCRIPTION - POWER STEERING BELT . . 10
OPERATION
OPERATION-ACCESSORY DRIVE BELT....10
OPERATION-POWER STEERING BELT.....10
DIAGNOSIS AND TESTING - ACCESSORY
DRIVE BELT.........................11
REMOVAL
REMOVAL-ACCESSORY DRIVE BELT......11
REMOVAL...........................11
INSTALLATION
INSTALLATION-ACCESSORY DRIVE BELT . . 13
INSTALLATION-POWER STEERING BELT . . . 13
ACCESSORY DRIVE
SPECIFICATIONS - ACCESSORY BELT TENSION
ACCESSORY DRIVE
BELTGAUGE
2.5L DIESEL ENGINE
A/C Compressor/
GeneratorDynamic Tensioner
Power Steering Belt 300 N (67 lbs.)
BELT TENSIONER
REMOVAL
WARNING:: BECAUSE OF HIGH SPRING TENSION,
DO NOT ATTEMPT TO DISASSEMBLE THE AUTO-
MATIC BELT TENSIONER. THE TENSIONER IS SER-
VICED AS AN ASSEMBLY.
(1) Remove the power steering belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(2) Remove the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(3) Remove the belt tensioner retaining bolt and
remove tensioner (Fig. 1).
INSTALLATION
(1) Install belt tensioner and retaining bolt (Fig.
1). Torque bolt to 47 N´m (35ft. lbs.).(2) Install the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(3) Install the power steering belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
Fig. 1 BELT TENSIONER AND IDLER PULLEY
1 - BELT TENSIONER RETAINING BOLT
2 - BELT TENSIONER
3 - IDLER PULLEY
4 - VIBRATION DAMPER/CRANKSHAFT PULLEY
5 - VIBRATION DAMPER/CRANKSHAFT PULLEY RETAINING
BOLTS
RGACCESSORY DRIVE7a-9
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IDLER PULLEY
REMOVAL
(1) Remove the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
CAUTION: IDLER PULLEY RETAINING BOLT HAS
LEFT HAND THREAD
(2) Remove the idler pulley (Fig. 2).
INSTALLATION
(1) Install the idler pulley (Fig. 2). Torque retain-
ing bolt to 22 N´m (16 ft. lbs.).
(2) Install the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(3) Install the power steering belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
DRIVE BELTS
DESCRIPTION
DESCRIPTION - ACCESSORY DRIVE BELT
The accessory drive belt is a serpentine type belt
(Fig. 3). Satisfactory performance of these belts
depends on belt condition and proper belt tension.
DESCRIPTION - POWER STEERING BELT
The power steering belt is a serpentine type belt
(Fig. 3). Satisfactory performance of this belt depends
on condition of the belt.
OPERATION
OPERATION-ACCESSORY DRIVE BELT
The accessory drive belts form the link between
the engine crankshaft and the engine driven accesso-
ries.
OPERATION-POWER STEERING BELT
The power steering belt forms a link between the
engine crankshaft and the power steering pump.
Fig. 2 BELT TENSIONER AND IDLER PULLEY
1 - BELT TENSIONER RETAINING BOLT
2 - BELT TENSIONER
3 - IDLER PULLEY
4 - VIBRATION DAMPER/CRANKSHAFT PULLEY
5 - VIBRATION DAMPER/CRANKSHAFT PULLEY RETAINING
BOLTS
Fig. 3 ACCESSORY DRIVE BELT ROUTING
1 - GENERATOR
2 - IDLER PULLEY
3 - A/C COMPRESSOR CLUTCH
4 - POWER STEERING PUMP PULLEY
5 - POWER STEERING BELT
6 - CRANKSHAFT DAMPER/PULLEY
7 - BELT TENSIONER
8 - ACCESSORY DRIVE BELT
7a - 10 ACCESSORY DRIVERG
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DIAGNOSIS AND TESTING - ACCESSORY DRIVE BELT
CONDITION POSSIBLE CAUSES CORRECTIONS
INSUFFICIENT ACCESSORY
OUTPUT DUE TO BELT SLIPPAGE1. Belt too loose 1. (a) Replace belt (auto-tensioned
belts)
2. Faulty belt tensioner 2. Replace tensioner as necessary
3. Belt excessively glazed or worn 3. Replace belt
BELT SQUEAL WHEN
ACCELERATING ENGINE1. Belts too loose 1. Check and replace belt tensioner
if necessary
2. Belt glazed 2. Replace belt
BELT SQUEAK AT IDLE 1. Belts too loose 1. (a) Replace belt
2. Dirt or paint imbedded in belt 2. Replace belt
3. Non-uniform belt 3. Replace belt
4. Misaligned pulleys 4. Align accessories
5. Non-uniform groove or eccentric
pulley5. Replace pulley
BELT ROLLED OVER IN GROOVE
OR BELT JUMPS OFF1. Broken cord in belt 1. Replace belt
2. Belt too loose, or too tight 2. Replace belt
3. Misaligned pulleys 3. Align accessories
4. Non-uniform groove or eccentric
pulley4. Replace pulley
REMOVAL
REMOVAL-ACCESSORY DRIVE BELT
(1) Remove the power steering belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(2) Relieve tension on belt tensioner using a suit-
able wrench (Fig. 4) and lock tensioner with a drift
punch (Fig. 5).
(3) Remove the accessory drive belt.
REMOVAL
(1) Raise vehicle on hoist.
(2) Remove right front fender inner splash shield.
(3) Install power steering belt remover tool on
crankshaft damper (Fig. 6).
(4) Rotate engine clockwise to remove belt (Fig. 7).
RGACCESSORY DRIVE7a-11
DRIVE BELTS (Continued)
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