2003 FORD MUSTANG radiator cap

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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GENERAL PROCEDURES
Cooling System Draining, Filling and Bleeding
Draining
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).
CAUTION: The coolant must be recovered in a suitable, clean container for reuse. If the
coolant is contaminated, it must be recycled or disposed of correctly.
NOTE: Less than 80% of coolant capacity can be recovered with the engine in the vehicle. Dirty, rusty
or contaminated coolant should be drained and filled with new coolant.
1. Release the pressure in the cooling system by slowly turning the pressure relief cap one half turn counterclockwise or the radiator cap counterclockwise to the first stop. When the pressure
is released, remove the pressure relief cap/radiator cap.
2. Place a suitable container below the radiator draincock. If equipped, disconnect the coolant return hose at the fluid cooler. Open the draincock and drain the engine coolant.
zClose the radiator draincock.
Filling — 3.8L
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.
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.
When adding engine coolant, use a 50/50 mixture of engine coolant and deionized water. SECTION 303-
03A: Engine Cooling 2003 Mustang Workshop Manual Material
Item Specification
Motorcraft Premium Gold
Engine Coolant
VC
-7-A (in Oregon VC-7- B)
(yellow color) WSS-
M97B51-
A1 Klj . 1 ba
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To maintain the integrity of the coolant and the cooling system:
zAdd 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
was drained from the cooling system. Do not mix coolant types.
z Do not add/mix orange- colored Motorcraft Speciality Orange Engine Coolant VC- 2 or
equivalent meeting Ford specification WSS- M97B44-D. Mixing coolants may degrade the
coolant's corrosion protection.
z Do not add alcohol, methanol, or brine, or any engine coolants mixed with alcohol or
methanol antifreeze. These can cause engine damage from overheating or freezing.
z Do not mix with recycled coolant unless it meets the requirements of Ford specification
WSS- M97B51- A1. Not all coolant recycling processes meet these Ford specifications.
Use of such coolants can harm the engine and cooling system components.
NOTE: The addition of Motorcraft Cooling System Stop Leak Pellets, VC- 6, darkens Motorcraft
Premium Gold Engine Coolant from yellow to golden tan.
1. Place the heater temperature selector in the maximum cool position.
2. CAUTION: On 3.8L engines, the vent plug must be removed before radiator fill or
the engine may not fill completely.
NOTE: It is important to maintain engine coolant concentrate between 40 percent or - 24°C (-11°
F) and 60 percent or - 52°C (-62°F).
Fill the engine cooling system with 50/50 mixture of water and engine coolant.
3. After filling the engine cooling system, add coolant to the vent until full. Install the vent plug.
4. Leave the pressure relief cap off and run the engine until it reaches normal operating temperature.
5. Stop the engine and add the correct engine coolant mixture to the degas bottle/coolant expansion tank until the coolant level is between the COOLANT FILL LEVEL marks.
6. Turn the engine off and allow the cooling system to cool. Check the level in the degas bottle/coolant expansion tank, and add a 50/50 mix as needed. Filling — 4.6L (2V) Klj . 2 ba
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"COOLANT FILL LEVEL" marks and replace the pressure cap.
7. Select the maximum cool temperature setting.
8. Run the engine until it reaches operating temperature.
9. CAUTION: If the engine coolant temperature gauge does not move, the engine
coolant level in the engine is low and must be filled. Stop the engine, allow it to cool and
fill the cooling system.
Add the correct engine coolant mixture to the degas bottle until the coolant level is between the
"COOLANT FILL LEVEL" marks.
10. Repeat the two previous steps until the engine coolant mixture is between the "COOLANT FILL LEVEL" marks on the degas bottle. Turn off the engine and allow it to cool.
11. Check the freeze protection of the engine coolant mixture with the Battery/Anti- freeze Tester
014- R1060 or equivalent. Adjust freezing point range if necessary.
Filling — Cobra
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.
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.
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:
zAdd 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
was drained from the cooling system. Do not mix coolant types.
z Do not add/mix orange- colored Motorcraft Speciality Orange Engine Coolant VC- 2 or
equivalent meeting Ford specification WSS- M97B44-D. Mixing coolants may degrade the
coolant's corrosion protection.
z Do not add alcohol, methanol, or brine, or any engine coolants mixed with alcohol or
methanol antifreeze. These can cause engine damage from overheating or freezing.
z Do not mix with recycled coolant unless it meets the requirements of Ford specification
WSS- M97B51- A1. Not all coolant recycling processes meet these Ford specifications.
Use of such coolants can harm the engine and cooling system components.
NOTE: The addition of Motorcraft Cooling System Stop Leak Pellets, VC- 6, darkens Motorcraft
Premium Gold Engine Coolant from yellow to golden tan.
1. Check all hose clamps for correct tightness. Make sure the radiator draincock is closed.
2. Place the heater temperature selector in maximum cool position. Klj . 4 ba
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3. Remove the pressure cap from the cooling system reservoir and the fill plug from the engine
crossover tube.
4. CAUTION: Do not fill the cooling system through the reservoir only. Coolant will not
enter the engine. Only the reservoir and the radiator will be filled and engine overheating
will occur.
Add coolant into the fill neck on the engine crossover tube until coolant reaches the top of the fill
neck on the cooling system reservoir.
5. Install the cooling system pressure cap on the reservoir.
6. Continue to fill the cooling system at the engine crossover fill neck until full.
7. Install the engine crossover tube fill plug.
8. WARNING: To avoid the possibility of personal injury or damage to the vehicle, do
not operate the engine with the hood open until the fan has been first examined for
possible cracks and separation.
CAUTION: If the engine temperature gauge does not move, coolant level is low in
the engine and must be filled. Stop the engine, allow to cool, and fill the cooling system
as outlined.
Run the engine until the thermostat opens (coolant flowing through the radiator lower hose
becomes hot).
9. Stop the engine and allow to cool.
10. Add coolant to the engine crossover tube fill neck until the cooling system is full.
11. Install the fill plug.
12. Repeat the fill procedure if necessary.
Filling — Mach I
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.
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.
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:
zAdd 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 Klj . 5 ba
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was drained from the cooling system. Do not mix coolant types.
z Do not add/mix orange- colored Motorcraft Speciality Orange Engine Coolant VC- 2 or
equivalent meeting Ford specification WSS- M97B44-D. Mixing coolants may degrade the
coolant's corrosion protection.
z Do not add alcohol, methanol, or brine, or any engine coolants mixed with alcohol or
methanol antifreeze. These can cause engine damage from overheating or freezing.
z Do not mix with recycled coolant unless it meets the requirements of Ford specification
WSS- M97B51- A1. Not all coolant recycling processes meet these Ford specifications.
Use of such coolants can harm the engine and cooling system components. 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.
1. Remove the air intake scoop. For additional information, refer to Section 303 - 12 .
2. Check all hose clamps for correct tightness. Make sure the radiator draincock is closed.
3. Place the heater temperature selector in maximum cool position.
4. Remove the pressure cap from the cooling system reservoir and the fill plug from the engine crossover tube.
5. CAUTION: Do not fill the cooling system through the reservoir only. Coolant will not
enter the engine. Only the reservoir and the radiator will be filled and engine overheating
will occur.
Add coolant into the fill neck on the engine crossover tube until coolant reaches the top of the fill
neck on the cooling system reservoir.
6. Install the cooling system pressure cap on the reservoir.
7. Continue to fill the cooling system at the engine crossover fill neck until full.
8. Install the engine crossover tube fill plug.
9. WARNING: To avoid the possibility of personal injury or damage to the vehicle, do
not operate the engine with the hood open until the fan has been first examined for
possible cracks and separation.
CAUTION: If the engine temperature gauge does not move, coolant level is low in
the engine and must be filled. Stop the engine, allow to cool, and fill the cooling system
as outlined.
Run the engine until the thermostat opens (coolant flowing through the radiator lower hose
becomes hot).
10. Stop the engine and allow to cool.
11. Add coolant to the engine crossover tube fill neck until the cooling system is full.
12. Install the fill plug.
13. Repeat the fill procedure if necessary. Klj . 6 ba
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GENERAL PROCEDURES
Engine and Radiator Flushing
1. 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 has 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).
Once pressure is released, remove the pressure relief cap/radiator cap.
2. Drain the cooling system. For additional information, refer to Cooling System Draining, Filling and Bleeding in this section.
3. Remove the coolant thermostat. For additional information, refer to Thermostat — 3.8L ,
Thermostat — 4.6L(2V) or
Thermostat — 4.6L(4V) in this section.
SECTION 303-
03A: Engine Cooling 2003 Mustang Workshop Manual Special Tool(s)
Coolant System
Drain/Flush/Fill
164-
R3673 or equivalent Flush Kit
164-
R3658 or equivalent Drain Kit
164-
R3662 or equivalent
Material Item Specification
Motorcraft Premium Cooling
System Flush
VC-
1 or equivalent ESR-
M14P7-A Motorcraft Premium Gold
Engine Coolant
VC
-7-A (in Oregon VC-7- B)
(yellow color) WSS-
M97B51-
A1 Klj . 1 ba
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