2023 FORD F650/750 radiator cap

Note: Do not use stop leak pellets, cooling
system sealants, or non-specified additives
as they can cause damage to the engine
cooling or heating systems. Resulting
component damage may not be covered by
the vehicle Warranty.
It is very important to use prediluted
coolant approved to the correct
specification in order to avoid plugging the
small passageways in the engine cooling
system. See Cooling System Capacity
and Specification (page 297). Do not mix
different colors or types of coolant in your
vehicle. Mixing of engine coolants or using
an incorrect coolant may harm the engine
or cooling system components and may
not be covered by the vehicle Warranty.
Note: Coolants marketed for all makes and
models may not be approved to Ford
specifications and may cause damage to
the cooling system. Resulting component
damage may not be covered by the vehicle
Warranty.
If the coolant level is at or below the
minimum mark, add prediluted coolant
immediately.
For vehicles with overflow coolant systems
with a non-pressurized cap on the coolant
recovery system, add coolant to the
coolant recovery reservoir when the engine
is cool. Add prediluted coolant to the
maximum level. For all vehicles which have
a coolant degas system with a pressurized
cap, or if it is necessary to remove the
coolant pressure relief cap on the radiator,
follow these steps to add engine coolant:
1. Turn the engine off and let it cool.
2. Unscrew the cap slowly. Any pressure
escapes as you unscrew the cap.
3. Fill the coolant reservoir slowly with
prediluted engine coolant to within the
minimum and maximum range on the
engine coolant reservoir. If you
removed the radiator cap in an
overflow system, fill the radiator untilthe coolant is visible and the radiator
is almost full. If coolant is added to
bring the level within the minimum and
maximum range when the engine is not
cold, the system may remain under
filled.
4. Replace the coolant reservoir cap, turn
it clockwise until you feel a strong
resistance.
5. Check the coolant level in the coolant
reservoir the next few times you drive
your vehicle. If necessary, add enough
prediluted engine coolant to bring the
coolant level to the proper level.
Note:If prediluted coolant is not available,
use the approved antifreeze concentrate
diluting it to 50/50 with distilled water. See
Cooling System Capacity and
Specification (page 297). Using water that
has not been deionized may contribute to
deposit formation, corrosion or plugging of
the small cooling system passageways.
If you have to add more than 1.1 qt (1 L) of
engine coolant per month, have your
vehicle checked as soon as possible.
Operating an engine with a low level of
coolant can result in engine overheating
and possible engine damage.
Note:During normal vehicle operation, the
coolant may change color from orange to
pink or light red. As long as the coolant is
clear and uncontaminated, this color change
does not indicate the coolant has degraded
nor does it require the coolant to be drained,
the system to be flushed, or the coolant to
be replaced.
In case of emergency, you can add a large
amount of water without prediluted
coolant in order to reach a vehicle service
location. On arrival do the following:
1. Drain the cooling system.
2. Chemically clean the cooling system.
We recommend Motorcraft Premium
Cooling System Flush.
234
Maintenance

3. Refill with prediluted coolant as soon
as possible.
Water alone, without prediluted coolant,
can cause engine damage from corrosion,
overheating or freezing.
Do not use the following as a coolant
substitute:
• Alcohol.
• Methanol.
• Brine.
• Any coolant mixed with alcohol or
methanol antifreeze.
Alcohol and other liquids can cause engine
damage from overheating or freezing.
Do not add extra inhibitors or non-specified
additives to the coolant. These can be
harmful and compromise the corrosion
protection of the coolant.
Engine and Secondary Cooling
System Refill Procedure
The following procedure should be used
when refilling the engine or secondary
cooling systems after it has been drained
or become extremely low:
1. Before you remove the cap, turn the
engine off and let it cool.
2. When the engine is cool, wrap a thick
cloth around the cap. Slowly turn cap
counterclockwise until pressure begins
to release.
3. Step back when the pressure releases.
4. When you are sure that all the pressure
has been released, use the cloth to turn
the cap counterclockwise and then
remove it.
5. Slowly add prediluted engine coolant
to the coolant reservoir until the
coolant level is within the minimum
and maximum range as listed on the
reservoir.
6. Reinstall the pressure relief cap.7. Start and run the engine at 2000 rpm
for 2 minutes.
8. Shut engine off, and remove the
pressure relief cap as previously
outlined.
9. If required, add prediluted engine
coolant to the coolant reservoir until
the coolant level is within the minimum
and maximum range as listed on the
reservoir.
10. Engine cooling system: Repeat steps
5 through 9 until the coolant level has
stabilized (is no longer dropping after
each step) and the upper radiator
hose at the radiator is warm to the
touch (indicating that the engine
thermostat is open and coolant is
flowing through the radiator).
11. Check the secondary cooling system.
Repeat steps 1 through 10 until the
coolant level has stabilized (is no
longer dropping after each step) and
the lower passenger side of the
secondary radiator is warm to the
touch (indicating secondary
thermostat is open and coolant is
flowing through the entire system).
12. Check the coolant level in both
systems before you drive your vehicle
the next few times.
13. If necessary, add prediluted engine
coolant to the coolant reservoirs until
the coolant level is within the
minimum and maximum range as
listed on the reservoir. After any
coolant has been added, check the
coolant concentration.
Recycled Coolant
We do not recommend the use of recycled
coolant as an approved recycling process
is not yet available.
235
Maintenance

It is very important to use prediluted
coolant approved to the correct
specification in order to avoid plugging the
small passageways in the engine cooling
system. See Cooling System Capacity
and Specification (page 298). Do not mix
different colors or types of coolant in your
vehicle. Mixing of engine coolants or using
an incorrect coolant may harm the engine
or cooling system components and may
not be covered by the vehicle Warranty.
Note: Coolants marketed for all makes and
models may not be approved to our
specifications and may cause damage to
the cooling system. Resulting component
damage may not be covered by the vehicle
Warranty.
If the coolant level is at or below the
minimum mark, add prediluted coolant
immediately.
For vehicles with overflow coolant systems
with a non-pressurized cap on the coolant
recovery system, add coolant to the
coolant recovery reservoir when the engine
is cool. Add prediluted coolant to the
maximum level. For all vehicles which have
a coolant degas system with a pressurized
cap, or if it is necessary to remove the
coolant pressure relief cap on the radiator,
follow these steps to add engine coolant:
1. Turn the engine off and let it cool.
2. Unscrew the cap slowly. Any pressure
escapes as you unscrew the cap.
3. Fill the coolant reservoir slowly with
prediluted engine coolant to within the
minimum and maximum range on the
engine coolant reservoir. If you
removed the radiator cap in an
overflow system, fill the radiator until
the coolant is visible and the radiator
is almost full. If coolant is added to
bring the level within the minimum and
maximum range when the engine is not
cold, the system may remain
underfilled.4. Replace the coolant reservoir cap. Turn
the cap clockwise until it contacts the
hard stop.
5. Check the coolant level in the coolant
reservoir the next few times you drive
your vehicle. If necessary, add enough
prediluted engine coolant to bring the
coolant level to the proper level.
Note:If prediluted coolant is not available,
use the approved antifreeze concentrate
diluting it to 50/50 with distilled water. See
Cooling System Capacity and
Specification (page 298). Using water that
has not been deionized may contribute to
deposit formation, corrosion or plugging of
the small cooling system passageways.
If you have to add more than 1.1 qt (1 L) of
engine coolant per month, have your
vehicle checked as soon as possible.
Operating an engine with a low level of
coolant can result in engine overheating
and possible engine damage.
Note:During normal vehicle operation, the
coolant may change color from orange to
pink or light red. As long as the coolant is
clear and uncontaminated, this color change
does not indicate the coolant has degraded
nor does it require the coolant to be drained,
the system to be flushed, or the coolant to
be replaced.
Note:In case of emergency, you can add a
large amount of water without coolant in
order to reach a vehicle service location.
Water alone, without coolant, can cause
engine damage from corrosion, overheating
or freezing. When you reach a service
location, you must have the cooling system
drained, flushed and refilled using the
correct specification prediluted coolant or
antifreeze concentrate. See Cooling
System Capacity and Specification (page
298).
239
Maintenance