2008 Mercury Mountaineer engine overheat

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 in vehicles originally equipped with Motorcraft Premium Gold
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%.
•Increased engine coolant concentrations above 60% will
decrease the overheat 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
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%.
•Decreased engine coolant concentrations below 40% will
decrease the corrosion protection characteristics of the engine
coolant and may cause engine damage.
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•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 (4.6L V8 engine only)
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.
Fail-safe cooling and engine oil overheat mode (4.6L V8 only)
If the engine coolant and/or engine oil overheat, the vehicle’s fail-safe
modes will reduce engine power to limit engine damage, even with a
total loss of coolant. The vehicle’s range and/or speed will be reduced,
depending on vehicle load, terrain, and outside temperatures.
The instrument cluster provides warnings for each mode.
•Fail-Safe Cooling Mode:The
(Service engine
soon),
(Engine oil pressure), and(Engine coolant
temperature) indicators will be on.
Along with these warning indicators, the engine coolant temperature
gauge will read in the Hot (H) area.
If the engine coolant reaches even hotter temperatures, fail-safe
cooling mode limits engine power more and disables air conditioning.
The engine will switch to alternating cylinder operation to help cool
the engine. The engine will run rough in this mode.
If continued operation increases the engine coolant temperature to a
critical range, the engine will shut down. Steering and braking effort
will increase. Once engine coolant temperature cools, the engine can
be restarted.
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•Engine Oil Overheat Mode:The(Engine coolant temperature)
indicator will be on. The instrument cluster has no separate oil
temperature indicator.
Along with the
(Engine coolant temperature) indicator, the engine
coolant temperature gauge will read in the Hot (H) area.
Oil overheat can be triggered in severe driving conditions, such as
towing heavy loads over mountainous terrain in extreme hot
temperatures. As oil temperature increases, engine and vehicle speed
will be limited. The transmission will also shift differently.
When the engine oil has cooled, the vehicle will perform normally.
When fail-safe cooling mode is activated
You have limited engine power when in the fail-safe mode, so drive the
vehicle with caution. Remember that the engine is capable of completely
shutting down automatically to prevent engine damage, therefore:
1. Pull off the road as soon as safely possible and turn off the engine.
2. Arrange for the vehicle to be taken to an authorized dealer.
3. If this is not possible, wait approximately 15 minutes for the engine to
cool.
4. Check the coolant level and replenish if low. Look for coolant leakage
in the engine compartment and under the vehicle.
Never remove the coolant reservoir cap while the engine is
running or hot.
5. Restart the engine and take your vehicle to an authorized dealer.
Driving the vehicle without repairing the engine problem
increases the chance of engine damage. Take your vehicle to an
authorized dealer as soon as possible.
FUEL FILTER
For fuel filter replacement, see your authorized dealer. Refer to
scheduled maintenance informationfor the appropriate intervals for
changing the fuel filter.
Replace the fuel filter with an authorized Motorcraft part. The
customer warranty may be void for any damage to the fuel system
if an authorized Motorcraft fuel filter is not used.
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