Cooling System: Description and Operation

Engine Cooling

NOTICE: The engine cooling system is filled with Motorcraft(R) Premium Gold Engine Coolant. Mixing coolant types degrades the corrosion protection of Motorcraft(R) Premium Gold Engine Coolant.

NOTE: The addition of Cooling System Stop Leak Pellets darkens Motorcraft(R) Premium Gold Engine Coolant from yellow to golden tan.

The cooling system components are the:

- block heater (if equipped).
- radiator.
- bypass tube.
- pressure relief cap.
- degas bottle.
- radiator draincock.
- coolant pump.
- coolant temperature indicator sender unit.
- thermostat housing.
- auxiliary coolant flow pump, refer to Heating and Air Conditioning for removal and installation and for diagnostics.

The degas bottle has 2 reservoirs and 2 pressure relief caps. The front (larger) reservoir and pressure relief cap are part of the engine cooling system. The rear (smaller) reservoir and pressure relief cap are part of the Motor Electronics Cooling System (MECS). The 2 reservoirs are separate and both cooling systems are independent of each other. For information on the MECS, refer to Transmission Cooler, A/T.

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 distilled water.

To maintain the integrity of the coolant and the cooling system:

- NOTE: The addition of Cooling System Stop Leak Pellets darkens Motorcraft(R) Premium Gold Engine Coolant from yellow to golden tan.

Add Motorcraft(R) Premium Gold Engine Coolant or equivalent (yellow color). Do not mix coolant types.

- Do not add/mix orange-colored Motorcraft(R) Specialty Orange Engine Coolant or equivalent meeting Ford specification WSS-M97B44-D or green-colored Motorcraft(R) Premium Engine Coolant or equivalent (green color) meeting Ford specification ESE-M97B44-A or equivalent. 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 WSS-M97B51-A1. Not all coolant recycling processes meet this Ford specification. Use of such a coolant may harm the engine and cooling system components. Do not mix coolant types.



Coolant Flow Diagram

NOTE: Black arrows indicate hot, white arrows indicate cold.