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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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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?

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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

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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?

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

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When you change a head gasket do you have to change the water pump and the thermostat also?

You might as well change the Thermostat because it is comparatively inexpensive, but test the water pump to see if it needs to be replaced.

How do you know if the thermostat is bad on your 1993 mercury cougar 3.8?

In my experience with my 93 cougar, you can tell that the thermostat is bad by one of two ways. First, it overheats. If it overheats the thermostat is in the closed position and it is not opening up to allow the cooler water to enter the engine. Second, if during the winter the temperature gauge will not move up and the heater is blowing cold air, then the thermostat is stuck in the open position and is not allowing the water in the block to warm up. In either scenario, you should probably replace it. They are really inexpensive and can be replaced with little to no trouble. You will, however, need to drain about a gallon or so of the antifreeze so that the fluid level is below the thermostat housing. When refilling the antifreeze make sure you remove the bolt on the top of the engine so that it will allow the air to escape. Hope this helps.

How do flush radiator in 1999 cougar?

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