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when a thermostat fails, it stops all water flow. the engine heats up but the radiator stays cold. start car, watch temp needle on dash. when engine temp reading is in mid-range, shut off car, go feel radiator with hand. if very warm or hot, thermosat probably okay. if cool or room-temp to the touch, thermostat is failed shut. My way: drain the coolant, remove the thermostat housing, pull out the thermostat and look at it. is it shut? if it is, it is bad, and replace it. put good one in, carefully clean thermostat housing with soap, water, scrape off scale with razor blade, NOT CUTTING INTO ALUMINIM sealing surface, apply RTV red to a thoroughly degreased and scraped surface on the engine, and re-install thermostat housing. re-tighten fasteners 24-hours later to take up slack in RTV as it sets.

when a water pump fails, it begins to leak coolant out of a small weep-hole on the pump body, to show that its seal has failed. It then starts to make a squealing or chirring noise, and then, when it seizes, it breaks the drive belt and makes a horrible, unmistakable noise like the roof of the car being torn off. If the pump turns quietly and normally, it works just fine.

when the coolant is low due to a small leak, the system is not always refilled correctly, and can look like it is not cooling after it was just filled (but incorrectly, with lots of trapped air still in the system).

If your cooling system was ever over-heated, fully and seriously, the thermostat was probably damaged. It should be replaced ($10) to avoid the fun and excitement of blowing the head gasket ($550).

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โˆ™ 2015-07-16 18:26:20
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Q: How do you tell if a 1989 Mercury Cougar needs a water pump or thermostat?
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Where is the thermostat located on a 1999 Mercury Mystique?

The thermostat for a 1999 Mercury Mystique is inside of the top water inlet. Remove the top radiator hose from the engine, and then inlet can be removed to get to the thermostat.

How do you change out the thermostat in 2000 Mercury Villager Estate?

Remove the water supply hose from the top of your 2000 Mercury Villager thermostat housing. Remove the thermostat housing retaining bolts. The old thermostat will simply lifts out. Drop in the new thermostat and reverse the process.

What causes a 1993 Mercury Cougar to keep running hot after 15 to 30 minutes when you can find no leaks and the thermostat has been replaced?

Bad cooling fan or thermal relay. Bad water pump, clogged radiator.

How much does a water pump cost on a 1995 Mercury Cougar?

Call your local parts store.

What is connected to the thermostat on a 1995 mercury villager?

depends is it the thermostat housing or the gasket. it is either connected to the hose or the water pump

How do you replace the water pump on a 1999 Mercury Cougar?

Take off old water pump and put on new very easy.

Do you use dex-cool anti-freeze in your 1996 Mercury Cougar?

( No ) a 1996 Mercury Cougar came from the factory with a 50 / 50 mix of distilled water and GREEN color antifreeze ( meeting Ford specification ESE-M97B44-A )

How can you tell if a fuse or thermostat or water pump needs to be replaced on a 1995 Mercury Tracer when the warning comes on when it is started and the engine overheated with water in the radiator?

Check engine. Is radiator really full? Does the rad. fan come on? Is the fan belt on water pump tight? If these things are ok, you probably need a new thermostat.

You have water coming out of your exhaust on a 1995 mercury cougar?

For some reason the gas is not completely combusting causing water to be expelled in the exhaust pipe.

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