Cooling System: Description and Operation

DESCRIPTION AND OPERATION

CAUTION: Some vehicle cooling systems are filled with Motorcraft Premium Engine Coolant VC-4-A (in Oregon VC-5, in Canada CXC-10) or equivalent meeting Ford specification ESE-M97B44-A (green color). Others 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:
- block heater
- Engine Coolant Temperature (ECT) sensor
- fan blade, fan motor and fan shroud assembly
- radiator pressure relief cap
- radiator draincock water pump
- water thermostat oil filter adapter
- radiator overflow hose
- upper radiator hose
- lower radiator hose
The radiator overflow hose circulates the coolant.
The water thermostat:
- controls the engine coolant temperature.
- allows for quicker engine warm-up.
The degas bottle/coolant expansion tank:
- provides a location for service fill.
- contains coolant expansion and system pressurization.
- provides air separation during operation
- replenishes the engine coolant to the system.
The engine coolant flows:
- from the lower radiator hose to the water pump.
- from the water pump to the engine block and the cylinder heads.
The 3.8L cooling system components include the:
- block heater
- Engine Coolant Temperature (ECT) sensor
- fan blade, fan motor and fan shroud assembly radiator
- radiator cap
- radiator draincock
- water pump
- water thermostat
- oil filter adapter
- radiator overflow hose
- coolant expansion tank upper radiator hose
- lower radiator hose
The fan blade draws air through the radiator to help cool the engine coolant.
The fan motor:
- operates only when the ignition switch is in the RUN position.
- will not operate with the switch in the OFF position.
The engine coolant:
- flows through the radiator tubes and is cooled by passing air over the cooling fins.
- is then circulated from the radiator outlet tank through the water pump and into the cylinder block to complete the circuit.
A closed water thermostat returns the engine coolant to the water pump. An open water 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 clean, drinkable water.
To maintain the integrity of the coolant and the cooling system:

NOTE: 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 Engine Coolant VC-4-A (in Oregon VC-5, in Canada CXC-10) or equivalent meeting Ford specification ESE-M97B44-A (green color), or Motorcraft Premium Gold Engine Coolant VC-7-A (in Oregon VC-7-B) or equivalent meeting Ford specification WSS-M97B51-AI (yellow color). Use the same coolant that is present in the cooling system. Do not mix coolant types.
Do not add/mix orange-colored Motorcraft Specialty Orange Engine Coolant VC-2 or equivalent meeting Ford specification WSS-M97B44-D. Mixing coolants may degrade the coolant's corrosion protection.
- 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 unless it meets the requirements of Ford specification ESE-M97B44-A or WSS-M97B51-A1. Not all coolant recycling processes meet these Ford specifications. Use of such coolants can harm the engine and cooling system components.
The water temperature sensor (4.6L) or cylinder head temperature sensor (3.8L) provides a signal to the temperature gauge.
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.