So, over the years, car thermostats, have not changed much.

In addition, they are fairly basic and continue to do a good job.

But, the job they do, is very important, so they have to function flawlessly. And, the result of it not working, can be very expensive.

So, thermostats open and close, to allow coolant flow when needed.

The thermostat must get the engine, to heat up to its optimum temperature, as quickly as possible. Also, once its at that optimum temperature, it must remain there. So, that the engine runs, at its peak performance. Consequently, the sooner that happens, the more efficient your engine will run. Without, you engine overheating.

Basically Thermostats Have Two Jobs

1- To accelerate engine warm-up time:

  • By blocking the circulation of coolant, between the engine and radiator; until the engine has reached its predetermined temperature.

2- To regulate the engine’s operating temperature:

  • By opening and closing in response, to specific changes in coolant temperature. Therefore, keeping the engine’s temperature, within the desired operating range.

So, How Do Thermostats Control The Flow Of Engine Coolant:

  • When the engine is cold, the thermostat is normally closed; restricting coolant flow to the radiator. As a result, allowing the engine to “warm up”.
  • As the engine warms, the increase in heat, causes the wax to melt and expand. Consequently, pushing against a piston, inside a rubber boot.
  • This forces the piston outward, opening the thermostat. So, coolant can start to circulate, between the engine and radiator.
  • As heat increases, it opens, until engine cooling requirements are satisfied.
  • If the temperature of the circulating coolant begins to drop, the wax element contracts. As a result, allowing spring tension to close the thermostat; which decreases coolant flow through the radiator.

Of course, there are outside influences which; may affect the temperature of the engine as well. The temperature of the environment around you, is a perfect example of this. But, as long as you have a functional thermostat; then it will know when to perform either task.

Choose Your Help Topic Below

Thermostat Issues – Is Your Coolant Flowing Properly

Electronic MAP-Controlled Thermostats – Provide Several Benefits

Thermostat Problems – Will Affect Your Engines Performance

Thank You !