2021 LINCOLN NAVIGATOR engine overheat

REDUCED ENGINE PERFORMANCE
WARNING: If you continue to drive
your vehicle when the engine is
overheating, the engine could stop without
warning. Failure to follow this instruction
could result in the loss of control of your
vehicle.
If the engine coolant temperature gauge
needle moves to the upper limit position, the
engine is overheating.
See Gauges (page
127).
You must only drive your vehicle for a short
distance if the engine overheats. The
distance you can travel depends on ambient
temperature, vehicle load and terrain. The
engine continues to operate with limited
power for a short period of time.
If the engine temperature continues to rise,
the fuel supply to the engine reduces. The
air conditioning switches off and the engine
cooling fan operates continually. 1. Gradually reduce your speed and stop
your vehicle as soon as it is safe to do
so.
2. Immediately switch the engine off to prevent severe engine damage.
3. Wait for the engine to cool down.
4. Check the coolant level.
See Engine
Coolant Check (page 383).
5. Have your vehicle checked as soon as possible.
ECONOMICAL DRIVING
Fuel economy is affected by several things
such as how you drive, the conditions you
drive under and how you maintain your
vehicle.
There are some things to keep in mind that
may improve your fuel economy:
• Accelerate and slow down in a smooth,
moderate fashion.
• Drive at steady speeds.
• Anticipate stops; slowing down may
eliminate the need to stop. •
Combine errands and minimize
stop-and-go driving (When running
errands, go to the furthest destination
first and then work your way back home).
• Close the windows for high-speed
driving.
• Drive at reasonable speeds.
• Keep the tires properly inflated and use
only the recommended size.
• Use the recommended engine oil.
• Perform all regularly scheduled
maintenance.
There are also some things you may want to
avoid doing because they reduce your fuel
economy:
• Avoid sudden or hard accelerations.
• Avoid revving the engine before turning
off the car.
• Avoid long idle periods.
• Do not warm up your vehicle on cold
mornings.
• Reduce the use of air conditioning and
heat.
• Avoid using speed control in hilly terrain.
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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.
In case of emergency, you can add a large
amount of water without engine coolant in
order to reach a vehicle service location. In
this instance, qualified personnel:
1. Must drain the cooling system.
2. Chemically clean the coolant system.
3. Refill with engine coolant as soon as possible.
Water alone, without engine 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 additives to
the coolant. These can be harmful and
compromise the corrosion protection of the
coolant.
Recycled Coolant
We do not recommend the use of recycled
coolant as an approved recycling process is
not yet available.
Dispose of used engine coolant in an
appropriate manner. Follow your
community's regulations and standards for
recycling and disposing of automotive fluids.
Severe Climates
If you drive in extremely cold climates:
•
It may be necessary to increase the
coolant concentration above 50%.
• A coolant concentration of 60% provides
improved freeze point protection.
Coolant concentrations above 60%
decrease the overheat protection
characteristics of the coolant and may
cause engine damage.
If you drive in extremely hot climates:
• You can decrease the coolant
concentration to 40%.
• Coolant concentrations below 40%
decrease the freeze and corrosion
protection characteristics of the coolant
and may cause engine damage.
Vehicles driven year-round in non-extreme
climates should use prediluted coolant for
optimum cooling system and engine
protection.
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Coolant Change
At specific mileage intervals, as listed in the
scheduled maintenance information, the
coolant should be changed. Add prediluted
coolant approved to the correct specification.
See Capacities and Specifications (page
440).
Fail-Safe Cooling
Fail-safe cooling allows you to temporarily
drive your vehicle before any incremental
component damage occurs. The fail-safe
distance depends on ambient temperature,
vehicle load and terrain.
How Fail-Safe Cooling Works If the engine begins to overheat,
the coolant temperature gauge
moves toward the red zone:
A warning lamp illuminates and a
message may appear in the
information display. If the engine reaches a preset
over-temperature condition, the engine
automatically switches to alternating cylinder
operation. Each disabled cylinder acts as an
air pump and cools the engine.
When this occurs, your vehicle still operates,
however:
•
Engine power is limited.
• The air conditioning system turns off.
Continued operation increases the engine
temperature, causing the engine to
completely shut down. Your steering and
braking effort increases in this situation.
When the engine temperature cools, you can
re-start the engine. Have your vehicle
checked as soon as possible to minimize
engine damage. When Fail-Safe Mode Is Activated WARNING: Fail-safe mode is for use
during emergencies only. Operate your
vehicle in fail-safe mode only as long as
necessary to bring your vehicle to rest in
a safe location and seek immediate repairs.
When in fail-safe mode, your vehicle will
have limited power, will not be able to
maintain high-speed operation, and may
completely shut down without warning,
potentially losing engine power, power
steering assist, and power brake assist,
which may increase the possibility of a
crash resulting in serious injury. WARNING:
Do not remove the
coolant reservoir cap when the engine is
on or the cooling system is hot. Wait 10
minutes for the cooling system to cool
down. Cover the coolant reservoir cap with
a thick cloth to prevent the possibility of
scalding and slowly remove the cap.
Failure to follow this instruction could result
in personal injury.
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Your vehicle has limited engine power when
in the fail-safe mode, drive your vehicle with
caution. Your vehicle does not maintain
high-speed operation and the engine may
operate poorly.
Remember that the engine is capable of
automatically shutting down to prevent
engine damage. In this situation:
1. Pull off the road as soon as safely
possible and switch the engine off.
2. If you are a member of a roadside assistance program, we recommend that
you contact your roadside assistance
service provider.
3. If this is not possible, wait a short period
for the engine to cool.
4. Check the coolant level. If the coolant level is at or below the minimum mark,
add prediluted coolant immediately.
5. When the engine temperature cools, you
can re-start the engine. Have your vehicle
checked as soon as possible to minimize
engine damage.
Note: Driving your vehicle without repair
increases the chance of engine damage. Engine Coolant Temperature
Management (If Equipped) WARNING:
To reduce the risk of
crash and injury, be prepared that the
vehicle speed may reduce and the vehicle
may not be able to accelerate with full
power until the coolant temperature
reduces.
If you tow a trailer with your vehicle, the
engine may temporarily reach a higher
temperature during severe operating
conditions, for example ascending a long or
steep grade in high ambient temperatures.
At this time, you may notice the coolant
temperature gauge moves toward the red
zone and a message may appear in the
information display. You may notice a reduction in vehicle speed
caused by reduced engine power in order
to manage the engine coolant temperature.
Your vehicle may enter this mode if certain
high-temperature and high-load conditions
take place. The amount of speed reduction
depends on vehicle loading, grade and
ambient temperature. If this occurs, there is
no need to stop your vehicle. You can
continue to drive.
The air conditioning may automatically turn
on and off during severe operating
conditions to protect the engine from
overheating. When the coolant temperature
decreases to the normal operating
temperature, the air conditioning turns on.
If the coolant temperature gauge moves fully
into the red zone, or if the coolant
temperature warning or service engine soon
messages appear in your information display,
do the following:
1.
Stop your vehicle as soon as it is safe to
do so. Fully apply the parking brake, shift
into park (P) or neutral (N).
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Your vehicle is equipped with the Intelligent
Oil-Life Monitor system, which displays a
message in the information display at the
proper oil change interval. This interval may
be up to one year or 10,000 mi (16,000 km).
When the oil change message appears in
the information display, it is time for an oil
change. Make sure you perform the oil
change within two weeks or 500 mi (800 km)
of the message appearing. Make sure you
reset the Intelligent Oil-Life Monitor after
each oil change. See Oil Change Indicator
Reset
(page 381).
If your information display resets prematurely
or becomes inoperative, you should perform
the oil change interval at six months or
5,000 mi (8,000 km)
from your last oil
change. Never exceed one year or 10,000 mi
(16,000 km)
between oil change intervals.
Your vehicle is very sophisticated and built
with multiple, complex, performance systems.
Every manufacturer develops these systems
using different specifications and
performance features. That is why it is
important to rely upon your dealership to
properly diagnose and repair your vehicle. The Lincoln Motor Company has
recommended maintenance intervals for
various parts and component systems based
upon engineering testing. The Lincoln Motor
Company relies upon this testing to
determine the most appropriate mileage for
replacement of oils and fluids to protect your
vehicle at the lowest overall cost to you and
recommends against maintenance schedules
that deviate from the scheduled maintenance
information.
We strongly recommend the use of only
genuine Lincoln, Motorcraft or Lincoln
authorized re-manufactured replacement
parts engineered for your vehicle.
Additives and Chemicals
This owner's manual and the Lincoln
Workshop Manual list the recommended
additives and chemicals for your vehicle. We
do not recommend using chemicals or
additives not approved by us as part of your
vehicle
’s normal maintenance. Please consult
your warranty information. Oils, Fluids and Flushing
In many cases, fluid discoloration is a normal
operating characteristic and, by itself, does
not necessarily indicate a concern or that the
fluid needs to be changed. However, a
qualified expert, such as the factory-trained
technicians at your dealership, should
inspect discolored fluids that also show signs
of overheating or foreign material
contamination immediately.
Make sure to change your vehicle
’s oils and
fluids at the specified intervals or in
conjunction with a repair. Flushing is a viable
way to change fluid for many vehicle
sub-systems during scheduled maintenance.
It is critical that systems are flushed only with
new fluid that is the same as that required
to fill and operate the system or using a
Lincoln approved flushing chemical.
Owner Checks and Services
Make sure you perform the following basic
maintenance checks and inspections every
month or at six-month intervals.
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