radiator cap FORD MUSTANG 2003 Workshop Manual

1. If compression improves considerably, piston rings are faulty.
2. If compression does not improve, valves are sticking or seating incorrectly.
3. If two adjacent cylinders indicate low compression pressures and squirting oil on each piston
does not increase compression, the head gasket may be leaking between cylinders. Engine oil
or coolant in cylinders could result from this condition.
Use the Compression Pressure Limit Chart when checking cylinder compression so that the
lowest reading is within 75 percent of the highest reading.
Cylinder Leakage Detection
When a cylinder produces a low reading, use of the Engine Cylinder Leak Detection/Air Pressurization
Kit will be helpful in pinpointing the exact cause.
The leakage detector is inserted in the spark plug hole, the piston is brought up to dead center on the
compression stroke, and compressed air is admitted.
Once the combustion chamber is pressurized, a special gauge included in the kit will read the
percentage of leakage. Leakage exceeding 20 percent is excessive.
While the air pressure is retained in the cylinder, listen for the hiss of escaping air. A leak at the intake
valve (6507) will be heard in the throttle body (9E926). A leak at the exhaust valve (6505) can be
heard at the tail pipe. Leakage past the piston rings will be audible at the positive crankcase ventilation
(PCV) connection. If air is passing through a blown head gasket to an adjacent cylinder, the noise will
be evident at the spark plug hole of the cylinder into which the air is leaking. Cracks in the cylinder
block or gasket leakage into the cooling system may be detected by a stream of bubbles in the radiator
(8005).
Oil Consumption Test
The following diagnostic procedure is used to determine the source of excessive internal oil
consumption. 1. NOTE: Oil use is normally greater during the first 16,100 km (10,000 miles) of service. As
mileage increases, oil use generally decreases. Vehicles in normal service should get at least
1,450 km per liter (900 miles per quart) after 16,000 km (10,000 miles) of service. High speed
driving, towing, high ambient temperature and other factors may result in greater oil use.
Define excessive oil consumption, such as the number of miles driven per liter (quart) of oil
used. Also determine customer's driving habits, such as sustained high speed operation,
towing, extended idle and other considerations.
2. Verify that the engine has no external oil leak as described under Engine Oil Leaks in the Diagnosis and Testing portion of this section.
3. Verify that the engine has the correct oil level dipstick (6750).
4. Verify that the engine is not being run in an overfilled condition. Check the oil level at least five minutes after a hot shutdown with the vehicle parked on a level surface. In no case should the
level be above MAX or the letter F in FULL. If significantly overfilled, carry out Steps 6a through
6d.
5. Verify the spark plugs are not oil saturated. If the spark plugs are oil saturated and compression is good it can be assumed the valve seals or valve guides are at fault. Klj . 9 ba
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SPECIFICATIONS
SECTION 303-
03A: Engine Cooling 2003 Mustang Workshop Manual General Specifications
Item Specification
Cooling System Capacity 15.2 L (4.0 gal)
Coolant Type
Motorcraft Premium Gold Engine Coolant VC-7-
A in
(Oregon VC -7-B) (yellow color) WSS-
M97B51- A1 Other Chemicals
Motorcraft Premium Cooling System Flush VC-
1 ESR-
M14P7-A Premium Long Life Grease XG-1-
C ESA-
M1C75- B Cooling System Stop Leak Pellets
VC-
6 ESE-
M99B37- B5 except as noted in ES-
F65E-19A511- AA Gasket Adhesive TA-
6 WSS-
M2G408- A Cooling System Pressure Test Specifications 138 kPa (20 psi)
Radiator Cap Pressure Test Specifications 110 kPa (16 psi)
Thermostat Opening Temperatures
Starts to open (4.6L 2V) 87-
93°C (192- 199°F) Starts to open (3.8L) 86.7-
90.6°C (189- 196°F) Starts to open (Cobra) 80-
83°C (175- 182°F) Fully open 104°C (219°F)
Torque Specifications Description Nm lb-
ft lb-
in Accelerator cable bracket bolts 10 — 89
Cylinder block drain plug 20 15 —
Exhaust manifold to EGR valve tube nut 35 26 —
Fan shroud bolts 10 — 89
Fan motor bolts 10 — 89
Degas bottle nuts 10 — 89
Coolant expansion tank bracket bolts 10 — 89
Radiator support bracket bolts 30 22 —
Transmission fluid cooler fittings 30 22 —
Coolant outlet connection bolts (3.8L) 10 — 89
Bypass tube bracket bolts (3.8L) 10 — 89
Bypass tube bolts (4.6L) 10 — 89
Bypass tube nuts (Supercharged engine) 25 18 —
Coolant hose mounting bolt 25 18 — Klj . 1 ba
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DESCRIPTION AND OPERATION
Engine Cooling
CAUTION: 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.
The 4.6L 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 pressure relief cap
z radiator draincock
z coolant pump
z coolant thermostat
z oil filter adapter
z radiator overflow hose
z upper radiator hose
z lower radiator hose
The radiator overflow hose circulates the coolant.
The coolant thermostat:
zcontrols the engine coolant temperature.
z allows for quicker engine warm- up.
The degas bottle/coolant expansion tank:
zprovides a location for service fill.
z contains coolant expansion and system pressurization.
z provides air separation during operation.
z replenishes the engine coolant to the system.
The engine coolant flows:
zfrom the lower radiator hose to the coolant pump.
z from the coolant pump to the engine block and the cylinder heads.
SECTION 303-
03A: Engine Cooling 2003 Mustang Workshop Manual Klj . 1 ba
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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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„
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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