2011 LINCOLN NAVIGATOR engine overheat

5. Fill the coolant reservoir slowly with the proper coolant mixture, to
within the COLD FILL RANGE or the FULL COLD level on the reservoir.
If you removed the radiator cap in an overflow system, fill the radiator
until the coolant is visible and radiator is almost full.
6. Replace the cap. Turn until tightly installed. Cap must be tightly
installed to prevent coolant loss.
After any coolant has been added, check the coolant concentration (refer
toChecking engine coolant). If the concentration is not 50/50
(protection to –34°F/–36°C), drain some coolant and adjust the
concentration. It may take several drains and additions to obtain a 50/50
coolant concentration.
Whenever coolant has been added, the coolant level in the coolant
reservoir should be checked the next few times you drive the vehicle. If
necessary, add enough 50/50 concentration of engine coolant and
distilled water to bring the liquid level to the proper level.
If you have to add more than 1.0 quart (1.0 liter) of engine coolant per
month, have your authorized dealer check the engine cooling system.
Your cooling system may have a leak. Operating an engine with a low
level of coolant can result in engine overheating and possible engine
damage.
Recycled engine coolant
Ford Motor Company does NOT recommend the use of recycled engine
coolant since a Ford-approved recycling process is not yet available.
Used engine coolant should be disposed of in an appropriate
manner. Follow your community’s regulations and standards for recycling
and disposing of automotive fluids.
Coolant refill capacity
To find out how much fluid your vehicle’s cooling system can hold, refer
toMaintenance product specifications and capacitiesin this chapter.
Fill your engine coolant reservoir as outlined inAdding engine coolant
in this section.
Severe climates
If you drive in extremely cold climates (less than –34°F [–36°C]):
•It may be necessary to increase the coolant concentration
above 50%.
•NEVER increase the coolant concentration above 60%.
Maintenance and Specifications
308
2011 Navigator(nav)
Owners Guide, 1st Printing
USA(fus)

•A coolant concentration of 60% will provide freeze point
protection down to -62°F [-52°C]. Increased engine coolant
concentrations above 60% will decrease the overheat
protection characteristics of the engine coolant and may cause
engine damage.
•If available, refer to the chart on the coolant container to
ensure the coolant concentration in your vehicle will provide
adequate freeze protection at the temperatures in which you
drive in the winter months.
If you drive in extremely hot climates:
•It is still necessary to maintain the coolant concentration
above 40%.
•NEVER decrease the coolant concentration below 40%.
•A coolant concentration of 40% will provide freeze point
protection down to -12°F [-24°C]. Decreased engine coolant
concentrations below 40% will decrease the corrosion/freeze
protection characteristics of the engine coolant and may cause
engine damage.
•If available, refer to the chart on the coolant container to
ensure the coolant concentration in your vehicle will provide
adequate protection at the temperatures in which you drive.
Vehicles driven year-round in non-extreme climates should use a 50/50
mixture of engine coolant and distilled water for optimum cooling system
and engine protection.
What you should know about fail-safe cooling
If the engine coolant supply is depleted, this feature allows the vehicle to
be driven temporarily before incremental component damage is incurred.
The “fail-safe” distance depends on ambient temperatures, vehicle load
and terrain.
How fail-safe cooling works
If the engine begins to overheat:
•The engine coolant temperature gauge will move to the red (hot)
area.
•The engine coolant temperature
symbol will illuminate.
•The
indicator light will illuminate.
If the engine reaches a preset over-temperature condition, the engine
will automatically switch to alternating cylinder operation. Each disabled
cylinder acts as an air pump and cools the engine.
Maintenance and Specifications
309
2011 Navigator(nav)
Owners Guide, 1st Printing
USA(fus)