What You Should Know About Fail-Safe Cooling - Lincoln Navigator 2000 Owner's Manual

• decreased engine coolant concentrations below 40% will
decrease the freeze protection characteristics of the engine
coolant and may cause engine damage.
• 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
symbol will illuminate.
• the
symbol will illuminate.
• the Service Engine Soon
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.
When this occurs the vehicle will still operate. However:
• the engine power will be limited.
• the air conditioning system will be disabled.
Continued operation will increase the engine temperature:
• the engine will completely shut down.
• steering and braking effort will increase.
Maintenance and care
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