How to replace a thermostat in a cooling system on Mercury Mountaineer?

Check the coolant level, drive belt tension, and temperature gauge before blaming the thermostat for cooling issues. If the engine warms up slowly or runs hot without a hot upper radiator hose, the thermostat may be stuck open or closed and need replacing. Don't drive without a thermostat as it affects emissions and fuel economy. To replace, disconnect the negative battery terminal, drain the cooling system, and remove the alternator harness bracket or engine trim cover. Find the thermostat housing by tracing the upper radiator hose to the engine, loosen the hose clamp, and remove the deteriorated hose if needed. Replace the thermostat housing cover if damaged. Remove the fasteners, detach the thermostat cover, remove the thermostat, clean off old gasket residue, fit a new gasket, and secure the thermostat housing cover, then refill the cooling system and start the engine. Let it reach normal temperature and check for leaks and proper functioning.

Genuine Mercury Mountaineer Thermostat

Engine Coolant Thermostat

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6 Thermostats found

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Mercury Mountaineer Thermostat Assembly
Part Number: 7L3Z-8575-B
$19.62 MSRP: $32.00
You Save: $12.38 (39%)
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Product Specifications
- Other Name: Thermostat Assy
- Replaced by: 7L3Z-8575-E
- Warranty: This genuine part is guaranteed by Ford's factory warranty.
Fits the following Vehicles:
- 2002-2010 Mercury Mountaineer | 8 Cyl 4.6L, 8 Cyl 4.6L Romeo SOHC EFI | 5-Speed Automatic Transmission 5R55S, 5-Speed Automatic Transmission 5R55W, 5-Speed Manual Transmission (M5R4), 6-Speed Automatic Transmission (6R80), 6-Speed Automatic Transmission 6R60, Four-Wheel Drive (Full Time) (Left Hand Drive), Four-Wheel Drive (Part Time) (Left Hand Drive), Four-Wheel Drive (Part Time) (Right Hand Drive), Left Hand Drive, Rear-Wheel Drive (Left Hand Drive)
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Mercury Mountaineer Thermostat Assembly
Part Number: 2L2Z-8575-AA
$20.65 MSRP: $33.45
You Save: $12.80 (39%)
Ships in 1-2 Business Days
ADD TO CART
Product Specifications
- Other Name: Thermostat Assy; Thermostat
- Replaces: 1L2Z-8575-AA
- Warranty: This genuine part is guaranteed by Ford's factory warranty.
Fits the following Vehicles:
- 2002-2010 Mercury Mountaineer | 6 Cyl 4.0L SOHC EFI | 5-Speed Automatic Transmission 5R55S, 5-Speed Automatic Transmission 5R55W, 5-Speed Manual Transmission (M5R4), 6-Speed Automatic Transmission (6R80), 6-Speed Automatic Transmission 6R60, Four-Wheel Drive (Full Time) (Left Hand Drive), Four-Wheel Drive (Part Time) (Left Hand Drive), Four-Wheel Drive (Part Time) (Right Hand Drive), Left Hand Drive, Rear-Wheel Drive (Left Hand Drive)
View related parts
Mercury Mountaineer Thermostat Assembly
Part Number: 1L2Z-8575-AA
$20.65 MSRP: $33.45
You Save: $12.80 (39%)
Ships in 1-2 Business Days
ADD TO CART
Product Specifications
- Other Name: Thermostat Assy
- Replaced by: 2L2Z-8575-AA
- Warranty: This genuine part is guaranteed by Ford's factory warranty.
Fits the following Vehicles:
- 2002 Mercury Mountaineer | 6 Cyl 4.0L SOHC EFI | 5-Speed Automatic Transmission 5R55S, 5-Speed Automatic Transmission 5R55W, 5-Speed Manual Transmission (M5R4), 6-Speed Automatic Transmission (6R80), 6-Speed Automatic Transmission 6R60, Four-Wheel Drive (Full Time) (Left Hand Drive), Four-Wheel Drive (Part Time) (Left Hand Drive), Four-Wheel Drive (Part Time) (Right Hand Drive), Left Hand Drive, Rear-Wheel Drive (Left Hand Drive)
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Mercury Mountaineer Thermostat Assembly
Part Number: F7TZ-8575-A
$32.35 MSRP: $53.09
You Save: $20.74 (40%)
Ships in 1-2 Business Days
ADD TO CART
Product Specifications
- Other Name: Thermostat Assy
- Manufacturer Note: Thermostat, SOHC
- Replaced by: YU3Z-8575-AA
- Warranty: This genuine part is guaranteed by Ford's factory warranty.
Fits the following Vehicles:
- 1998-2001 Mercury Mountaineer | 6 Cyl 4.0L | 4AT 4R70W, 5AT 5R55E
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Mercury Mountaineer Thermostat Assembly
Part Number: XL2Z-8575-AB
Product Specifications
- Other Name: Thermostat Assy
- Manufacturer Note: #XL2E 8575-AB (same as XL2Z 8575-AA, except new and improved jiggle pin), FROM 8/9/99
- Replaced by: XR3Z-8575-BA
- Warranty: This genuine part is guaranteed by Ford's factory warranty.
Fits the following Vehicles:
- 1999-2001 Mercury Mountaineer | 8 Cyl 5.0L | 4AT 4R70W, 5AT 5R55E
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Mercury Mountaineer Thermostat Assembly
Part Number: AL2Z-8575-A
Product Specifications
- Other Name: Thermostat Assy
- Replaced by: AL2Z-8575-B
- Warranty: This genuine part is guaranteed by Ford's factory warranty.
Fits the following Vehicles:
- 2006-2010 Mercury Mountaineer | 6 Cyl 4.0L SOHC EFI | 5-Speed Automatic Transmission 5R55S, 5-Speed Automatic Transmission 5R55W, 5-Speed Manual Transmission (M5R4), 6-Speed Automatic Transmission (6R80), 6-Speed Automatic Transmission 6R60, Four-Wheel Drive (Full Time) (Left Hand Drive), Four-Wheel Drive (Part Time) (Left Hand Drive), Four-Wheel Drive (Part Time) (Right Hand Drive), Left Hand Drive, Rear-Wheel Drive (Left Hand Drive)

Mercury Mountaineer Thermostat

The Thermostat on the Mercury Mountaineer controls engine temperature so the vehicle remains under ideal conditions. The closed loop controlling device that is positioned close to the radiator senses the coolant temperature and opens or closes the route of fluid to the radiator. Thus, it helps to turn the cooling on and off, providing cooling that keeps its parts healthy and performance strong. The original designs utilized robust mechanical constructions, like bimetallic strips or wax pellets that expand and contract when subjected to rising heat, which is a simple yet reliable method still applied for normal driving. Subsequent iterations of the Mountaineer series come equipped with digitally monitored units that retain the same wax pellet valve, plus a simple electronic signal for faster feedback. More importantly, plumbing doesn't change, which gives drivers stable readings. The Thermostat, regardless of generation, stands as the key link between cold startup and fully warmed power in order to avoid sluggish behavior and overheating. The consistent Thermostat response is critical because the cooling capacity of the Mercury is balanced around it. As a result, each Mercury Mountaineer delivers smooth trips in different climates. Furthermore, a dependable Thermostat protects the engine of every Mercury Mountaineer. In addition, another Thermostat sensor alerts the driver to any irregularities.

We provide a wide range of Mercury Mountaineer Thermostat at the optimal prices. If you need Mercury Mountaineer Thermostat, you can shop with confidence on our website. All our OEM parts come with a manufacturer's warranty and are delivered to your doorstep with a fast delivery service.

Mercury Mountaineer Thermostat Parts Questions & Experts Answers

Thermostat Assembly
2L2Z-8575-AA
Q: How to replace a thermostat in a cooling system on Mercury Mountaineer?
A:
Check the coolant level, drive belt tension, and temperature gauge before blaming the thermostat for cooling issues. If the engine warms up slowly or runs hot without a hot upper radiator hose, the thermostat may be stuck open or closed and need replacing. Don't drive without a thermostat as it affects emissions and fuel economy. To replace, disconnect the negative battery terminal, drain the cooling system, and remove the alternator harness bracket or engine trim cover. Find the thermostat housing by tracing the upper radiator hose to the engine, loosen the hose clamp, and remove the deteriorated hose if needed. Replace the thermostat housing cover if damaged. Remove the fasteners, detach the thermostat cover, remove the thermostat, clean off old gasket residue, fit a new gasket, and secure the thermostat housing cover, then refill the cooling system and start the engine. Let it reach normal temperature and check for leaks and proper functioning.