Ford 2003 Mustang Workshop Manual page 1845

Visual Inspection Chart
Mechanical
Leaks
Hoses
Hose clamps
Water gasket
Head gaskets
Intake manifold gasket
Coolant pump
Radiator
Degas bottle/coolant expansion tank
Heater core
Fan/fan clutch
Engine coolant temperature sensor (4.6L)
Cylinder head temperature sensor (3.8L)
Circuitry
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
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
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:
Section 303-00 .
Section 303-00 .