In a well maintained cooling system the thermostat will last for many years. As coolant ages, the additives that prevent corrosion are depleted. This causes a huge amount of damage to the system and can cause thermostats to stick. If the thermostat sticks open, the engine runs too cold and waste fuel.
http://www.agcoauto.com/content/news/p2_articleid/191
How a Thermostat Works. 1  When the engine is cold, the thermostats is normally closed; restricting flow to the radiator allowing the engine to “warm up”. 2  As the engine warms, the increase in heat causes the wax to melt and expand, pushing against a piston inside a rubber boot.
http://www.stant.com/index.php/english/products/consumer-products/thermostats/abcs-thermostats/
A thermostat fails “open” if the return spring breaks or debris prevents the thermostat valve from fully seating or closing; allowing a steady flow of coolant to the radiator, overcooling the engine. 1  This results in poor warm up and heater performance, increased engine emissions and reduced fuel economy.
http://www.stant.com/index.php/english/products/consumer-products/thermostats/abcs-thermostats/
The problem with a low temp thermostat then for regular driving is that there are times when the car will be running at a temperature lower than it's design intended. The result is increased wear on the engine's internals.
http://www.tuneruniversity.com/blog/2012/04/low-temp-thermostats-whats-the-advantage/
Once you're moving, on the highway, with a 160 degree thermostat on a cooler day you could be cruising at 160-180 degrees (opening temp->designed operating temp). This is possible because the load on the engine is low and the outside temps are low. Therefore, the thermostat opening temp maters somewhat here.
http://www.tuneruniversity.com/blog/2012/04/low-temp-thermostats-whats-the-advantage/
Many thermostats have a “jiggle pin” or “check valve” that allows trapped air in the cooling system to pass through the thermostat and be released from the system. If a Stant thermostat does not have a jiggle pin, it will have a bleed notch” or other method of removing air from the system.
http://www.stant.com/index.php/english/products/consumer-products/thermostats/abcs-thermostats/
NEXT PAGENEXT. ­. ­Any liquid-cooled car engine has a small device called the thermostat that sits between the engine and the radiator. The thermostat in most cars is about 2 inches (5 cm) in diameter. Its job is to block the flow of coolant to the radiator until the engine has warmed up.
http://auto.howstuffworks.com/question248.htm
The biggest misunderstanding about thermostats is that people believe they make the engine run cooler. They don't necessarily do that. The cooling system and load on the engine determines how hot the engine gets, the thermostat fully open will still be the mercy of the coolant system's ability to remove heat.
http://www.tuneruniversity.com/blog/2012/04/low-temp-thermostats-whats-the-advantage/
Cooler thermostats. Pretty much every hop-up guide for every car out there lists switching to a cooler thermostat as one of the first mods you should do to increase performance. The reasoning behind it is that engine will run cooler, and the cooler the engine the more power it will make. This is true to a certain extent, but it's not as simple as that. In modern cars I think it's a bad idea to run a cooler thermostat without doing a little homework first. First of all, most new cars have a much more sophisticated method for regulating heat than they did back in the day when engine temperature was solely controlled by the thermostat and and engine-turned fan.
http://hotrodscott.blogspot.com/2007/08/cooler-thermostats.html
When a thermostat sticks closed the engine will overheat. Overheating causes cylinder heads to expand greatly. This has the effect of crushing the cylinder head gasket and can crack the head[s]. Pistons also expand and gall the cylinder walls. Overheating, even for a short while can severely damage the engine.
http://www.agcoauto.com/content/news/p2_articleid/191
why use a cooler thermostat in a car engine
The cooler thermostat in a car engine is to block the flow of coolant to the radiator until the engine has warmed up. A cooler thermostat is used in a car engine to block the flow of coolant to the radiator until the engine has warmed up.