LINCOLN NAUTILUS 2021 Owners Manual
Manufacturer: LINCOLN, Model Year: 2021, Model line: NAUTILUS, Model: LINCOLN NAUTILUS 2021Pages: 579, PDF Size: 6.9 MB
Page 341 of 579

Engine coolant reservoir. See Checking the Coolant (page 340).
A
Brake fluid reservoir.
See Checking the Brake Fluid (page 218).
B
Battery.
See Changing the 12V Battery (page 345).
C
Power distribution box.
See Accessing the Under Hood Fuse Box (page 316).
D
Air filter assembly.
See Changing the Engine Air Filter (page 344).
E
Engine oil dipstick.
See Engine Oil Dipstick Overview (page 338).
F
Engine oil filler cap.
See Adding Engine Oil (page 338).
G
Windshield washer fluid reservoir.
See Adding Washer Fluid (page 118).
H
337
2021 Nautilus (CD9) Canada/United States of America, enUSA, Edition date: 202011, First-Printing Maintenance
Page 342 of 579

ENGINE OIL
Engine Oil Dipstick Overview - 2.0L
Minimum.
A
Nominal.
B
Maximum.
C Engine Oil Dipstick Overview - 2.7L
Minimum.
A
Nominal.
B
Maximum.
C
Checking the Engine Oil Level
1. Make sure that your vehicle is on level ground.
2. Check the oil level before starting the engine, or switch the engine off after
warming up and wait 10 minutes for the
oil to drain into the oil pan. 3. Remove the dipstick and wipe it with a
clean, lint-free cloth.
4. Reinstall the dipstick and make sure it is
fully seated.
5. Remove the dipstick again to check the oil level.
Note: If the oil level is between the maximum
and minimum marks, the oil level is
acceptable. Do not add oil.
6. If the oil level is at the minimum mark, immediately add oil.
7. Reinstall the dipstick. Make sure it is fully
seated.
Note: The oil consumption of new engines
reaches its normal level after approximately
3,000 mi (5,000 km).
Adding Engine Oil WARNING:
Do not remove the filler
cap when the engine is running.
338
2021 Nautilus (CD9) Canada/United States of America, enUSA, Edition date: 202011, First-Printing MaintenanceE270482 E250320
Page 343 of 579

WARNING: Do not add engine oil
when the engine is hot. Failure to follow
this instruction could result in personal
injury.
Do not use supplemental engine oil additives
because they are unnecessary and could
lead to engine damage that the vehicle
warranty may not cover.
1. Clean the area surrounding the engine oil filler cap before you remove it.
2. Remove the engine oil filler cap.
3. Add engine oil that meets our specifications.
See Capacities and
Specifications (page 402).
4. Reinstall the engine oil filler cap. Turn it clockwise until you feel a strong
resistance.
Note: Do not add oil further than the
maximum mark. Oil levels above the
maximum mark may cause engine damage.
Note: Immediately soak up any oil spillage
with an absorbent cloth. Resetting the Engine Oil Change
Reminder
Use the information display controls on the
steering wheel to reset the oil change
indicator.
From the main menu scroll to:
Action and description
Message
Press the right arrow button,
then from this menu scroll to
the following message.
Settings
Press the right arrow button,
then from this menu scroll to
the following message.
Vehicle
Press the right arrow button,
then from this menu scroll to
the following message.
Oil Life
Press and hold the OK button
until the instrument cluster
displays the following
message.
Hold OK to
Reset
Reset Successful Action and description
Message
When the oil change indicator
resets the instrument cluster
displays 100%.
Remaining Life
{00}%
If the instrument cluster
displays one of the following
messages, repeat the
process.
Not Reset
Reset Cancelled
Engine Oil Capacity and Specification
For filling information, please refer to the
Capacities and Specifications section of your
owner's manual.
See Engine Oil Capacity
and Specification (page 404).
339
2021 Nautilus (CD9) Canada/United States of America, enUSA, Edition date: 202011, First-Printing Maintenance
Page 344 of 579

CHECKING THE COOLANT
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 459).
Note: Make sure that the coolant level is
between the minimum and maximum marks
on the coolant reservoir.
Note: Coolant expands when it is hot. The
level may extend beyond the
MAX mark.
If the coolant level is at or below the
minimum mark, add prediluted coolant
immediately.
Maintain coolant concentration within 48%
to 50%, which equates to a freeze point
between
-29°F (-34°C) and -35°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 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. WARNING:
Do not add engine
coolant when the engine is on or the
cooling system is hot. Failure to follow this
instruction could result in personal injury. WARNING:
Do not add coolant
further than the MAX mark. WARNING: Do not put coolant in the
windshield washer reservoir. If sprayed on
the windshield, coolant could make it
difficult to see through the windshield. 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.
Note: Automotive fluids are not
interchangeable.
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 407). 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 could void
the vehicle Warranty.
Note: If prediluted coolant is not available,
use the approved concentrated coolant
diluting it to 50/50 with distilled water.
See
Capacities and Specifications (page 407).
Using water that has not been deionized
may contribute to deposit formation,
corrosion and plugging of the small cooling
system passageways.
340
2021 Nautilus (CD9) Canada/United States of America, enUSA, Edition date: 202011, First-Printing Maintenance
Page 345 of 579

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.
341
2021 Nautilus (CD9) Canada/United States of America, enUSA, Edition date: 202011, First-Printing Maintenance
Page 346 of 579

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.
342
2021 Nautilus (CD9) Canada/United States of America, enUSA, Edition date: 202011, First-Printing Maintenance
Page 347 of 579

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.
343
2021 Nautilus (CD9) Canada/United States of America, enUSA, Edition date: 202011, First-Printing Maintenance
Page 348 of 579

CHANGING THE ENGINE AIR
FILTER
WARNING: To reduce the risk of
vehicle damage and personal burn injuries,
do not start your engine with the air
cleaner removed and do not remove it
while the engine is running.
When changing the air filter element, use
only the air filter element listed.
See
Capacities and Specifications (page 400).
For turbocharged equipped vehicles: When
servicing the air cleaner, it is important that
no foreign material enter the air induction
system. The engine and turbocharger are
susceptible to damage from even small
particles.
Change the air filter element at the proper
interval. See Scheduled Maintenance (page
459
). Note:
Failure to use the correct air filter
element may result in severe engine
damage. The customer warranty may be
void for any damage to the engine if the
correct air filter element is not used. 1. Release the clamps that secure the air
filter housing cover.
2. Carefully lift the air filter housing cover.
3. Remove the air filter element from the air
filter housing.
4. Wipe any dirt or debris from the air filter housing and cover to make sure no dirt
gets in the engine and to make sure you
have a good seal. 5.
Install a new air filter element. Be careful
not to crimp the filter element edges
between the air filter housing and cover.
This could cause filter damage and allow
unfiltered air to enter the engine if not
properly seated.
6. Install the air filter housing cover.
7. Engage the clamps to secure the air filter
housing cover to the air filter housing.
CHANGING THE FUEL FILTER
Your vehicle has a lifetime fuel filter that
integrates with the fuel tank. It does not need
regular maintenance or replacement.
344
2021 Nautilus (CD9) Canada/United States of America, enUSA, Edition date: 202011, First-Printing MaintenanceE144365
Page 349 of 579

DRIVE BELT ROUTING OVERVIEW
- 2.0L
A. The long drive belt is on the first pulley
groove closest to the engine.
B. The short drive belt is on the second pulley groove farthest from the engine. DRIVE BELT ROUTING OVERVIEW
- 2.7L CHANGING THE 12V BATTERY
WARNING: Batteries normally
produce explosive gases which can cause
personal injury. Therefore, do not allow
flames, sparks or lighted substances to
come near the battery. When working near
the battery, always shield your face and
protect your eyes. Always provide correct
ventilation. WARNING:
When lifting a
plastic-cased battery, excessive pressure
on the end walls could cause acid to flow
through the vent caps, resulting in personal
injury and damage to the vehicle or battery.
Lift the battery with a battery carrier or with
your hands on opposite corners.
345
2021 Nautilus (CD9) Canada/United States of America, enUSA, Edition date: 202011, First-Printing Maintenance E161383 E191903
Page 350 of 579

WARNING: Keep batteries out of
reach of children. Batteries contain sulfuric
acid. Avoid contact with skin, eyes or
clothing. Shield your eyes when working
near the battery to protect against possible
splashing of acid solution. In case of acid
contact with skin or eyes, flush immediately
with water for a minimum of 15 minutes and
get prompt medical attention. If acid is
swallowed, call a physician immediately. WARNING:
Battery posts, terminals
and related accessories contain lead and
lead compounds, chemicals known to the
State of California to cause cancer and
reproductive harm. Wash your hands after
handling
. WARNING:
This vehicle may have
more than one battery. Removing the
battery cables from only one battery does
not disconnect your vehicle electrical
system. Make sure you disconnect the
battery cables from all batteries when
disconnecting power. Failure to do so may
cause serious personal injury or property
damage.
The battery is in the engine compartment.
See
Under Hood Overview (page 334).
Your vehicle has a maintenance-free battery.
It does not require additional water during
service.
For longer, trouble-free operation, keep the
top of the battery clean and dry and the
battery cables tightly fastened to the battery
terminals. If any corrosion is present on the
battery or terminals, remove the cables from
the terminals and clean with a wire brush.
You can neutralize the acid with a solution
of baking soda and water. We recommend that you disconnect the
negative battery cable terminal from the
battery if you plan to store your vehicle for
an extended period.
Note:
If you only disconnect the negative
battery cable terminal, make sure it is
isolated or placed away from the battery
terminal to avoid unintended connection or
arcing.
To maintain correct operation of the battery
management system, if you add any
electrical devices to your vehicle, do not
connect the ground connection directly to
the negative battery terminal. A connection
at the negative battery terminal can cause
inaccurate measurements of the battery
condition and potential incorrect system
operation.
Note: If you add electrical accessories or
components to your vehicle this may
adversely affect battery performance,
durability and the performance of other
electrical systems on your vehicle.
If you replace the battery make sure it
matches the electrical requirements of your
vehicle.
346
2021 Nautilus (CD9) Canada/United States of America, enUSA, Edition date: 202011, First-Printing Maintenance