Cooling System: Description and Operation
Engine Cooling
NOTICE: Vehicle cooling systems are filled with Motorcraft(R) Specialty Orange Engine Coolant. Always fill the cooling system with the manufacturer's specified coolant. If a non-specified coolant has been used the cooling system must be chemically flushed. Refer to Cooling System Flushing . Failure to follow these instructions may damage the engine or cooling system.
NOTICE: During normal vehicle operation, Motorcraft Specialty Orange Engine Coolant may change color from orange to pink or light red. As long as the engine coolant is clear and uncontaminated, this color change does not indicate the engine coolant has degraded nor does it require the engine coolant to be drained, the system to be flushed, or the engine coolant to be replaced.
The cooling system consists of the following components:
- Block heater (located in the lower left hand corner of the engine block)
- Coolant crossover manifold assembly (located in front of the intake manifold)
- Coolant expansion tank
- Cooling fan motor and shroud
- Radiator
- Radiator draincock (located in the lower right hand corner)
- Upper and lower radiator hoses
- Bypass coolant hose
- Coolant pump
- Coolant thermostat
The coolant pump:
- circulates the coolant.
The coolant thermostat:
- controls coolant temperature.
- allows quicker engine warm-up.
The coolant expansion tank:
- holds surplus coolant when hot.
- allows coolant expansion.
- replenishes coolant to the system.
The fan motor:
- operates only when the ignition switch is in the RUN position.
- will not operate with the ignition switch in the OFF position.
The radiator:
- cannot be serviced. Install a new radiator.
- allows excess heat to be transferred to the air.
The optional block heater:
- electrical heating element is installed in the core plug opening.
- uses a standard 110V electrical supply
- keeps the engine coolant warm during cold weather.
NOTICE: 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. Failure to follow these instructions may damage the engine or cooling system.
When adding engine coolant, use a 50/50 mixture of engine coolant and distilled water. A coolant concentration of 50% provides freeze point protection down to -37°C (-34°F).
To maintain the integrity of the coolant and the cooling system:
- add Motorcraft(R) Specialty Orange Engine Coolant. Do not mix coolant types.
- 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.
- do not mix with recycled coolant. Use of such a coolant may harm the engine and cooling system components.
Coolant Flow Diagram, Expedition and Navigator without Auxiliary Heater
NOTE: Black arrows indicate hot, white arrows indicate cold.
Coolant Flow Diagram, Expedition and Navigator with Auxiliary Heater
NOTE: Black arrows indicate hot, white arrows indicate cold.
Coolant Flow Diagram, Expedition EL and Navigator L with Auxiliary Heater
NOTE: Black arrows indicate hot, white arrows indicate cold.
