2021 LINCOLN NAUTILUS engine overheat

To top up the coolant level do the following:
1. Unscrew the cap slowly. Any pressure
escapes as you unscrew the cap.
2. Add enough prediluted coolant to reach
the correct level.
Note: We do not recommend the use of
recycled coolant.
3. Replace the coolant reservoir cap. Turn the cap clockwise until it contacts the
hard stop.
4. Check the coolant level in the coolant reservoir the next few times you drive
your vehicle. If necessary, repeat step 2.
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.
Service your vehicle 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, as they can cause engine damage
from overheating or freezing:
•
Alcohol.
• Methanol.
• Brine.
• Any coolant mixed with alcohol or
methanol antifreeze.
Do not add extra inhibitors or additives to
the coolant. These can be harmful and
compromise the corrosion protection of the
coolant.
Severe Climates
If you drive in extremely cold climates, you
may need to increase the coolant
concentration above 50%. Note:
A coolant concentration of 60%
provides improved freeze point protection.
Coolant concentrations above 60% decrease
the overheat protection characteristics of
the coolant and could cause engine
damage.
If you drive in extremely hot climates, you
may need to decrease the coolant
concentration to 40%.
Note: Coolant concentrations below 40%
decrease the freeze and corrosion protection
characteristics of the coolant and could
cause engine damage.
Coolant Change
Change the coolant at specific mileage
intervals. Refer to the scheduled
maintenance information.
See Normal
Scheduled Maintenance (page 463).
Note: Dispose of used coolant in the
appropriate manner.
Follow your community's regulations and
standards for recycling and disposing of
automotive fluids.
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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.
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 could
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.
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3. If this is not possible, wait for a short
period of time 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).
2. Leave the engine running until the coolant temperature gauge needle
returns to the normal position. If the
temperature does not drop after several
minutes, follow the remaining steps.
3. Switch the engine off and wait for it to cool. Check the coolant level.
4. If the coolant level is at or below the minimum mark, add prediluted coolant
immediately.
5. If the coolant level is normal, restart the engine and continue.
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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.
You can drive high performance vehicles in
such a way that may lead to higher oil
consumption including extended time at high
engine speeds, high loads, engine braking,
hard cornering maneuvers, track and off-road
usage. Under these conditions, oil
consumption of approximately 1 quart per
500 miles (1 liter per 800 km) is possible.
Check the engine oil level at every refueling
and adjust to maintain proper levels to avoid
engine damage.
It is important to rely upon your dealership
to properly diagnose and repair your vehicle. We strongly recommend only using our
genuine or our authorized re-manufactured
replacement parts engineered for your
vehicle.
Additives and Chemicals
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. Have discolored
fluids that also show signs of overheating or
foreign material contamination checked
immediately. Make sure to change the 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 our
approved flushing chemical.
Owner Checks and Services
Make sure you perform the following basic
maintenance checks and inspections. Check Every Month
The air filter restriction gauge. 1
The engine oil level.
Function of all interior and the exterior lights.
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