Ford F-650 2018 Owner's Manual page 202

WARNINGS
Do not put coolant in the windshield
washer reservoir. If sprayed on the
windshield, coolant could make it
difficult to see through the windshield.
To reduce the risk of personal injury,
make sure the engine is cool before
unscrewing the coolant pressure
relief cap. The cooling system is under
pressure. Steam and hot liquid can come
out forcefully when you loosen the cap
slightly.
Do not add coolant further than the
MAX mark.
When the engine is cold, check the
concentration and level of the coolant at
the intervals listed in the scheduled
maintenance information. See Scheduled
Maintenance (page 320).
Note: Make sure that the coolant level is
between the MIN and MAX marks on the
coolant reservoir.
Note: Coolant expands when it is hot. The
level may extend beyond the MAX mark.
Maintain coolant concentration within
48% to 50%, which equates to a freeze
point between -30°F (-34°C) and -34°F
(-37°C). Coolant concentration should be
checked using a refractometer. We do not
recommend the use of hydrometers or
coolant test strips for measuring coolant
concentration.
Adding Coolant
WARNINGS
Do not add engine coolant when the
engine is hot. Failure to follow this
instruction could result in personal
injury.
Never remove the coolant reservoir
cap when the engine is running or
hot.
F650750 (TBC) , enUSA, Edition date: 201708, First Printing
Maintenance
Note: Automotive fluids are not
interchangeable. Do not use coolant or
windshield washer fluid outside of its
specified function and vehicle location.
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 Capacities and
Specifications (page 269). 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.
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