Engine Cooling

WARNING: This page is about a different car, the 2007 Lincoln Mark LT and 2007 Ford Pickup. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION: Vehicle cooling systems are filled with Motorcraft Premium Gold Engine Coolant (yellow color). Always fill the cooling system with the same type of coolant that was drained from the system. Do not mix coolant types. Mixing coolant types degrades the corrosion protection of Motorcraft Premium Gold Engine Coolant, and may result in damage to the cooling system.

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

The cooling system consists of the:

Block heater
Coolant crossover manifold assembly (4.6L, 5.4L)
Degas bottle
Fan blade
Mechanical fan clutch (4.2L)
Electronic fan clutch (4.6L, 5.4L)
Fan shroud
Radiator
Pressure relief cap
Radiator draincock
Upper and lower radiator hoses
Coolant pump
Coolant thermostat

The block heater:

warms the coolant during extreme cold weather conditions.
uses 110V AC electrical source.

The coolant crossover manifold:

provides for coolant flow between the cylinder heads.
houses the thermostat.
has an attachment for the heater hose.

The degas bottle:

holds surplus coolant when hot.
de-aerates the system reducing hot spots.
is the location for service fill.
allows coolant expansion and system pressurization.
replenishes coolant to the system.

The fan blade draws air through the radiator to help cool the system coolant.

The fan clutch controls the fan speed.

The fan shroud directs air flow through the radiator

The radiator:

allows excess heat to be transferred to the air.
cannot be serviced. Install a new radiator.

The pressure relief cap:

provides for cooling system pressurization.
is the location for service fill.

The radiator draincock:

provides for cooling system draining.

The radiator hoses:

allow coolant flow between the engine and the radiator

The coolant pump:

circulates the coolant.

The coolant thermostat:

controls coolant temperature.
allows quicker engine warm-up.

The engine coolant flows:

from the lower radiator hose to the coolant pump.
from the coolant pump to the engine block, the cylinder heads, heater core and PCV fittings.

thermostat closed, the coolant returns to the coolant pump.
thermostat open, the coolant flows back to the radiator for heat rejection.

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, or the engine may be damaged.

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

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:

Add Motorcraft Premium Gold Engine Coolant (yellow color). Do not mix coolant types.
Do not add orange-colored Motorcraft Specialty Orange Engine Coolant. Mixing coolants may degrade the coolant's protection rating.
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.

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

Fig 1: Identifying Coolant Flow Diagram - 4.2L

Courtesy of FORD MOTOR CO.

Item	Part Number	Description
1	18K580	Heater outlet hose
2	18K579	Heater inlet hose
3	18663	Heater coolant outlet tube assembly
4	9424	Upper intake manifold assembly
5	9J447	Lower intake manifold assembly
6	8A520	Coolant outlet tube assembly
7	8575	A/C evaporative and blower assembly
8	6050	LH cylinder head
9	6083	LH cylinder head gasket
10	6010	Cylinder block
11	8A080	Degas bottle
12	6049	RH cylinder head
13	8B273	Lower radiator hose assembly
14	8W005	Degas bottle inlet hose
15	8501	Coolant pump
16	6F008	Engine front cover and oil pump assembly
17	8575	Thermostat
18	8594	Thermostat housing
19	18K579	Heater inlet hose
20	8B274	Upper radiator hose
21	8005	Radiator

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

Fig 2: Identifying Coolant Flow Diagram - 4.6L (2V)

Courtesy of FORD MOTOR CO.

Item	Part Number	Description
1	18K579	Heater inlet hose
2	18K580	Heater outlet hoses
3	18465	Coolant hose
4	8594	Thermostat housing
5	8575	Thermostat
6	8C369	Coolant crossover manifold assembly
7	9A474	PCV fitting
8	9424	Intake manifold assembly
9	18465	Coolant hose
10	18B539	Heater core
11	18663	Coolant outlet tube
12	6049	LH cylinder head
13	6083	LH cylinder head gasket
14	8A080	Degas bottle
15	8C351	Degas bottle outlet hose
16	6010	Cylinder block
17	6881	Oil filter adapter
18	8B273	Lower radiator hose
19	8501	Coolant pump
20	6049	RH cylinder head
21	8W005	Degas bottle inlet hose
22	8005	Radiator
23	8B274	Upper radiator hose

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

Fig 3: Identifying Coolant Flow Diagram - 5.4L (3V)

Courtesy of FORD MOTOR CO.

Item	Part Number	Description
1	8B274	Upper radiator hose
2	18663	Coolant outlet tube
3	18K580	Heater outlet hose
4	18K579	Heater inlet hose
5	8597	Heater manifold tube
6	18456	Heater core
7	8594	Thermostat housing
8	8575	Thermostat
9	8C369	Coolant crossover manifold assembly
10	6049	LH cylinder head
11	8A080	Degas bottle
12	6010	Cylinder block
13	6083	LH cylinder head gasket
14	8C351	Degas bottle outlet hose
15	8B273	Lower radiator hose
16	6881	Oil filter adapter
17	8501	Coolant pump
18	6049	RH cylinder head
19	8W005	Degas bottle inlet hose
20	8005	Radiator