radiator FORD MUSTANG 2003 Repair Manual

The 3.8L cooling system components include the:
zblock heater
z engine coolant temperature (ECT) sensor
z fan blade, fan motor and fan shroud assembly
z radiator
z radiator cap
z radiator draincock
z coolant pump
z coolant thermostat
z oil filter adapter
z radiator overflow hose
z coolant expansion tank
z upper radiator hose
z lower radiator hose
The fan blade draws air through the radiator to help cool the engine coolant.
The fan motor:
zoperates only when the ignition switch is in the RUN position.
z will not operate with the switch in the OFF position.
The engine coolant:
zflows through the radiator tubes and is cooled by passing air over the cooling fins.
z is then circulated from the radiator outlet tank through the coolant pump and into the cylinder
block to complete the circuit.
A closed coolant thermostat returns the engine coolant to the coolant pump. An open coolant
thermostat allows the engine coolant to flow to the radiator.
CAUTION: Engine coolant provides freeze protection, boil protection, cooling efficiency,
and corrosion protection to the engine and cooling components. In order to obtain these
protections, the engine coolant must be maintained at the correct concentration and fluid level
in the degas bottle (4.6L) or coolant expansion tank (3.8L).
When adding engine coolant, use a 50/50 mixture of engine coolant and deionized water.
To maintain the integrity of the coolant and the cooling system:
zNOTE: The addition of Motorcraft Cooling System Stop Leak Pellets, VC-6, darkens Motorcraft
Premium Gold Engine Coolant from yellow to golden tan.
Add Motorcraft Premium Gold Engine Coolant VC-7- A (in Oregon VC-7-B) or equivalent
meeting Ford specification WSS- M97B51-A1 (yellow color). Use the same coolant that is
present in the cooling system. Do not mix coolant types.
z Do not add/mix orange-colored Motorcraft Speciality Orange Engine Coolant VC- 2 or equivalent Klj . 2 ba
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3. If the inspection reveals an obvious concern that can be readily identified, repair as necessary.
4.
CAUTION: Some vehicle cooling systems are filled with Motorcraft Premium Gold
Engine Coolant VC -7-A (in Oregon VC -7-B) or equivalent meeting Ford specification
WSS- M97B51- A1 (yellow color). Always fill the cooling system with the same coolant that
is present in the system. Do not mix coolant types.
NOTE: The addition of Motorcraft Cooling System Stop Leak Pellets, VC-6, darkens Motorcraft
Premium Gold Engine Coolant from yellow to golden tan.
Inspect the coolant condition. 1. Inspect the coolant color.
„If Motorcraft Premium Gold Engine Coolant (yellow color) VC-7- A (in Oregon VC-
7- B) or equivalent meeting Ford specification WSS-M97B51- A1 has a clear or
pale yellow color, this indicates higher water content than required.
„ Dark brown can indicate unauthorized stop leak may have been used. Use
Motorcraft Cooling System Stop Leak Pellets VC- 6 or equivalent meeting Ford
specification ESE-M99B37- 5 except as noted in ES-F6SE-19A511- AA only.
„ A light or reddish brown color indicates that rust may be present in the cooling
system. Flush the system and refill with the correct mixture of water and engine
coolant.
„ An iridescent sheen on top of the coolant can indicate a trace of oil is entering the
system. For additional information on engine diagnosis, refer to Section 303 - 00 .
„ A milky brown color may indicate that either engine oil or transmission fluid is
entering the cooling system. If transmission fluid is suspected, the cause may be a
leaky radiator. Pressure test the cooling system. For additional information, refer
to component tests in this section. If engine oil is suspected the cause of the leak
may be internal to the engine. For additional information, refer to Section 303 - 00 .
2. If the engine coolant appearance is acceptable, test the engine coolant freezing point
range with the battery and anti- freeze tester. The freezing point should be in the range -
40°C to - 20°C (-50°F to - 10°F). If the vehicle is driven in cold climates less than - 32°C (-
34°F), it may be necessary to increase the coolant concentration to get adequate freeze
protection.
„Maximum coolant concentration is 60% coolant/40% water.
„ Minimum coolant concentration is 40% coolant/60% water. 3. Adjust coolant range and level, if necessary: Visual Inspection Chart
Mechanical
z
Leaks
z Hoses
z Hose clamps
z Water gasket
z Head gaskets
z Intake manifold gasket
z Coolant pump
z Radiator
z Degas bottle/coolant expansion tank
z Heater core
z Fan/fan clutch
z Engine coolant temperature sensor (4.6L)
z Cylinder head temperature sensor (3.8L)
z Circuitry Klj . 2 ba
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„
If coolant is low, add specified coolant mixture only.
„ If the engine coolant tests too weak, add straight engine coolant until the readings
are within acceptable levels.
„ If the engine coolant tests strong, remove some of the engine coolant and add
water until the readings are within acceptable levels.
5. If the concern remains after the inspection, determine the symptom(s) and GO to Symptom Chart
Symptom Chart
Pinpoint Tests
PINPOINT TEST A: LOSS OF COOLANT
Symptom Chart Condition
Possible Sources Action
z Loss of coolant zRadiator.
z Coolant pump seal.
z Radiator hoses.
z Heater hoses.
z Heater core.
z Engine gaskets.
z Degas bottle or
coolant expansion
tank. z
Go To Pinpoint Test
A .
z The engine overheats zThermostat.
z Coolant pump.
z Internal engine coolant
leak.
z Radiator.
z Cooling fan.
z Pressure relief cap or
radiator cap. z
Go To Pinpoint Test
B .
z The engine does not reach
normal operating temperature z
Thermostat. zGo To Pinpoint Test
C .
Test Step Result / Action to Take
A1 CHECK THE ENGINE COOLANT LEVEL
WARNING: Never remove the pressure relief cap
while the engine is operating or when the cooling system is
hot. Failure to follow these instructions can result in
damage to the cooling system or engine or personal injury.
To avoid having scalding hot coolant or steam blow out of
the degas bottle when removing the pressure relief cap,
wait until the engine is cooled, then wrap a thick cloth
around the pressure relief cap and turn it slowly. Step back Yes
GO to
A2 .
No
REFILL the engine
coolant as necessary.
GO to A2 . Klj . 3 ba
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while the pressure is released from the cooling system.
When you are sure all the pressure has been released, turn
and remove the pressure relief cap (still with a cloth).
NOTE:
Allow the engine to cool before checking the engine
coolant level.
z Key in OFF position.
z Visually check the engine coolant level at the degas bottle or
coolant expansion tank.
z Is the engine coolant level within specification? A2 CHECK THE PRESSURE RELIEF CAP
z
Carry out the Cap— 3.8L or Cap—4.6L test. Go to Component
Tests in this section.
z Is pressure relief cap/radiator cap OK? Yes
GO to
A3 .
No
INSTALL a new
pressure relief
cap/radiator cap. TEST
the system for normal
operation. A3 CHECK THE ENGINE COOLANT FOR INTERNAL LEAK
z
Key in OFF position.
z Inspect the engine coolant in degas bottle/coolant expansion
tank for signs of transmission fluid or engine oil.
z Is oil or transmission fluid evident in the coolant? Yes
If engine oil is evident,
REFER to
Section 303 -
00 . If transmission fluid
is evident, REPAIR or
INSTALL a new radiator
as necessary.
No
GO to A4 .
A4 CHECK THE ENGINE AND THE TRANSMISSION FOR
COOLANT z
Remove the oil level dipstick from the engine and the
transmission.
z Is coolant evident in the oil or transmission fluid? Yes
If coolant is in engine,
REFER to
Section 303 -
00 . If coolant is in
transmission, REPAIR
or INSTALL a new
radiator as necessary.
To repair the automatic
transmission, REFER to
Section 307 - 01 .
No
GO to A5 .
A5 PRESSURE TEST THE ENGINE COOLING SYSTEM
z
Pressure test the engine cooling system. Go to Component
Tests in this section.
z Does the engine cooling system leak? Yes
REPAIR or install new
components. TEST the
system for normal
operation.
No
The cooling system is
operational. GO to
Symptom Chart
. Klj . 4 ba
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PINPOINT TEST B: THE ENGINE OVERHEATS
Test Step Result / Action to
Take B1 CHECK THE ENGINE COOLANT LEVEL
WARNING: Never remove the pressure relief cap while
the engine is operating or when the cooling system is hot.
Failure to follow these instructions can result in damage to
the cooling system or engine or personal injury. To avoid
having scalding hot coolant or steam blow out of the degas
bottle when removing the pressure relief cap, wait until the
engine is cooled, then wrap a thick cloth around the
pressure relief cap and turn it slowly. Step back while the
pressure is released from the cooling system. When you are
sure all the pressure has been released, turn and remove
the pressure relief cap (still with a cloth). NOTE: If the engine
is hot, allow the engine to cool before proceeding.
z Key in OFF position.
z Check the engine coolant level at the degas bottle/coolant
expansion tank.
z Is the engine coolant OK? Yes
GO to
B2 .
No
REFILL the engine
coolant at the degas
bottle/coolant
expansion tank. Go To Pinpoint Test A .
B2 CHECK THE COOLANT CONDITION
z
Check the coolant for dirt, rust or contamination.
z Is the coolant condition OK? Yes
GO to
B3 .
No
FLUSH the engine
cooling system.
REFER to Engine and Radiator Flushing in
this section. TEST the
system for normal
operation. B3 CHECK FOR AN AIRFLOW OBSTRUCTION
z
Inspect the A/C condenser core and radiator for obstructions
such as leaves or dirt.
z Is there an obstruction? Yes
REMOVE the
obstruction. CLEAN the
A/C condenser core
and radiator. TEST the
system for normal
operation.
No
GO to
B4 .
B4 CHECK THE WATER THERMOSTAT OPERATION
z
Start the engine and allow the engine to run for ten minutes.
z Feel the inlet and outlet heater water hoses and the underside of
the upper radiator hose.
z Are the upper radiator hose and the heater water hoses
cold? Yes
INSTALL a new water
thermostat. REFER to
Thermostat
— 3.8L ,
Thermostat — 4.6L(2V)
or
Thermostat — 4.6L
(4V) in this section.
TEST the system for
normal operation.
No
GO to B5 . Klj . 5 ba
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PINPOINT TEST C: THE ENGINE DOES NOT REACH NORMAL
OPERATING TEMPERATURE
Component Tests
Pressure Test —
3.8L
WARNING: Never remove the pressure relief cap while the engine is operating or when the
cooling system is hot. Failure to follow these instructions can result in damage to the cooling
system or engine or personal injury. To avoid having scalding hot coolant or steam blow out of
the degas bottle when removing the pressure relief cap, wait until the engine is cooled, then
wrap a thick cloth around the pressure relief cap and turn it slowly. Step back while the
pressure is released from the cooling system. When you are sure all the pressure has been
released, turn and remove the pressure relief cap (still with a cloth).
1. Remove the radiator cap. Fill the radiator as needed. Fit the pressure tester to the radiator neck, using an aftermarket adapter.
2. CAUTION: Do not pressurize the cooling system beyond 110 kPa (16 psi).
Pump the cooling system to a maximum of 102 kPa (14.9 psi) and hold for 2 minutes. If the
pressure drops within this time, inspect for leaks and repair as necessary. Pressure Test — 4.6L B5 CHECK THE COOLING FAN OPERATION
z
Carry out the cooling fan component tests. Go to Component
Tests.
z Is the cooling fan operation OK? Yes
For diagnosis and
testing of the engine,
REFER to
Section 303 -
00 .
No
INSTALL a new fan
component as
necessary. TEST the
system for normal
operation. Test Step Result / Action to Take
C1 CHECK THE ENGINE
TEMPERATURE z
Start the engine and allow the
engine to idle for ten minutes.
z Feel the inlet and heater water
hoses and the underside of the
upper radiator hose.
z Are the upper radiator hose
and the heater water hoses
cold? Yes
INSTALL a new water thermostat. REFER to
Thermostat
— 3.8L ,
Thermostat — 4.6L(2V) or
Thermostat — 4.6L(4V) in this section. TEST the system
for normal operation.
No
For diagnosis and testing of the engine coolant
temperature gauge, REFER to Section 413 - 01 . Klj . 6 ba
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1. Turn the engine OFF.
2.
WARNING: Never remove the pressure relief cap while the engine is operating or
when the cooling system is hot. Failure to follow these instructions can result in damage
to the cooling system or engine or personal injury. To avoid having scalding hot coolant
or steam blow out of the degas bottle when removing the pressure relief cap, wait until
the engine is cooled, then wrap a thick cloth around the pressure relief cap and turn it
slowly. Step back while the pressure is released from the cooling system. When you are
sure all the pressure has been released, turn and remove the pressure relief cap (still
with a cloth).
Check the engine coolant level; refer to Cooling System Draining, Filling and Bleeding in this
section.
3. Connect Radiator Heater Core Pressure Tester to the degas bottle nipple and vent hose. Install a pressure test pump to the quick- connect fitting of the test adapter.
4. CAUTION: Do not pressurize the cooling system beyond 152 kPa (22 psi).
NOTE: If the plunger of the pump is depressed too quickly, an erroneous pressure reading will
result.
Slowly depress the plunger of the pressure test pump until the pressure gauge reading stops
increasing and note the highest pressure reading obtained.
5. If the pressure relief cap does not hold pressure, remove and wash the pressure relief cap in clean water to dislodge all foreign particles from the gaskets. Check the sealing surface in the
filler neck.
6. If 110 kPa (16 psi) cannot be reached, install a new pressure relief cap. If more than 124 kPa (18 psi) shows on gauge, install a new pressure relief cap.
7. CAUTION: If the pressure drops, check for leaks at the engine- to-heater core hoses,
engine- to-radiator hoses, water valve hose (if applicable), oil cooler return tube gasket
(6N789), radiator and heater core or other system components and connections. Any
leaks which are found must be corrected and the system rechecked.
Pressurize the engine cooling system as described in Step 4 (using a pressure relief cap that
operates within the specified upper and lower pressure limits). Observe the gauge reading for
approximately two minutes; refer to General Specifications. Pressure should not drop during this
time.
8. Release the system pressure by loosening the pressure relief cap. Check the engine coolant level and replenish, if necessary, with the correct engine coolant mixture; refer to Cooling System Draining, Filling and Bleeding in this section.
Cap — 3.8L
1. Inspect the radiator cap and seals for damage or deterioration. Install a new radiator cap if necessary.
2. Fit the radiator cap to Radiator/Heater Core Pressure Tester Kit, using the aftermarket adapter.
3. NOTE: If the plunger of the pressure tester is depressed too fast, an incorrect pressure reading
will result. Slowly pump the pressure tester until the pressure gauge stops increasing and note the highest Klj . 7 ba
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pressure reading. Release pressure and repeat the test. Install a new radiator cap if the
pressure is not 99.3-
121.4 kPa (14.4-17.6 psi).
Cap — 4.6L
WARNING: Never remove the pressure relief cap while the engine is operating or when the
cooling system is hot. Failure to follow these instructions can result in damage to the cooling
system or engine or personal injury. To avoid having scalding hot coolant or steam blow out of
the degas bottle when removing the pressure relief cap, wait until the engine is cooled, then
wrap a thick cloth around the pressure relief cap and turn it slowly. Step back while the
pressure is released from the cooling system. When you are sure all the pressure has been
released, turn and remove the pressure relief cap (still with a cloth).
1. Remove the pressure relief cap from the degas bottle.
2. Follow the instructions from the pressure tester.
3. NOTE: If the plunger of the pump is depressed too quickly, an erroneous pressure reading will
result.
Slowly depress the plunger of the pressure test pump until the pressure gauge reading stops
increasing and note the highest pressure reading obtained.
4. If the pressure test gauge readings are not within specifications, install a new pressure relief cap. If the pressure test gauge readings are within specifications, carry out the cooling system
Pressure Test.
Thermostat — Water
A new water thermostat should be installed only after the following electrical and mechanical tests
have been carried out.
Thermostat — Electrical Test
CAUTION: Always vent the exhaust to the outside when carrying out this test.
NOTE: The electrical thermostat test is most accurate if carried out at less than 37.8°C (100°F)
ambient air. This test may be carried out with or without the hood open and with the engine warm or
cold.
1. Check the engine coolant level. Fill as needed.
2. With the ignition OFF, remove the engine coolant temperature (ECT) (4.6L) or cylinder head temperature (CHT) (3.8L) sensor harness connector and attach ECT (4.6L) or CHT (3.8L)
Sensor "T" Cable as a jumper between the powertrain control module (PCM) (12A650) and the
ECT (4.6L) or CHT (3.8L) sensor. Attach the 73III Automotive Meter to the ECT (4.6L) or CHT
(3.8L) Sensor "T" Cable. Voltage values (0- 5 V) may now be monitored while the sensor retains
its connection to the wiring harness.
An appropriate diagnostic tool may be used to monitor the ECT on vehicles equipped with data link connector (DLC). Klj . 8 ba
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3.
NOTE: Running this test with the vehicle in gear or with the A/C compressor clutch engaged
(running) will cause incorrect diagnosis.
Place the transmission in PARK (P) or NEUTRAL (N).
4. Start the engine and allow the engine to idle throughout this test. Allow the engine to run for 2 minutes, then record the ECT (4.6L) or CHT (3.8L) voltage. Record the ECT (4.6L) or CHT
(3.8L) voltage every 60 seconds. When the ECT (4.6L) or CHT (3.8L) voltage trend changes
direction or only changes slightly (0.03 volts or less) from the previous reading, record this as
the thermostat opening voltage. Use the voltage and corresponding coolant temperature chart
listed below for 4.6L engines only.
5. If the thermostat opening voltage is greater than 0.75 volts and less than 82°C (180°F), install a new water thermostat.
6. If the thermostat opening voltage is less than 0.75 volts and greater than 82°C (180°F), the water thermostat is good and a new water thermostat should not be installed. GO to Symptom Chart for further instructions.
Thermostat — Mechanical Test
1. Remove the water thermostat.
2. Check the water thermostat for seating. Hold the water thermostat up to a lighted background. Leakage of light around the thermostat valve at room temperature indicates that a new water
thermostat should be installed. Some water thermostats have a small leakage notch at one
location on the perimeter of the thermostat valve, which is considered normal.
3. Immerse the water thermostat in a boiling coolant and water mixture.
4. See the General Specifications chart for water thermostat opening temperatures.
Radiator Leak Test, Removed From the Vehicle CAUTION: Never leak test an aluminum radiator in the same water that copper/brass
radiators are tested in. Flux and caustic cleaners may be present in the cleaning tank and they
will damage aluminum radiators.
NOTE: Always install plugs in the oil cooler fittings before leak- testing or cleaning any radiator.
NOTE: Clean the radiator before leak- testing to avoid contamination of tank. Coolant Temperature °C (°F) ECT (Volts)
22 (71) 3.00
43 (109) 2.01
71 (159) 1.01
82 (180) 0.75
91 (195) 0.059
97 (206) 0.050
105 (221) 0.040 Klj . 9 ba
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1. Leak-
test the radiator in clean water with 138 kPa (20 psi) air pressure.
Fan — Electric Test
Refer to the Powertrain Control/Emissions Diagnosis (PC/ED) manual. Klj . 10 ba
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