What is the purpose of the automotive thermostat?

The automotive thermostat is what regulates the temperature and coolant flow within your automotive cooling system. Its job is to block the flow of coolant in the engine after a cold start, which allows the engine to heat up quickly.

The thermostat has a temperature sensitive wax pellet inside, that melts as the engine coolant reaches a certain temperature. As the wax melts it expands allowing the automotive thermostat to open. Once open, the engine coolant can circulate through the rest of the cooling system.

Once the engine is at its proper operating temperature, the fans operate to pull outside air through the radiator to cool down the coolant as it circulates through. As the coolant cools down, the wax contracts again causing the thermostat to close slightly, thus regulating
temperature and flow.

Generally, an automotive thermostat will rarely fail. The most common cause of failure would be that the internal piston of the thermostat sticks on the shaft, not allowing it to open or close. This is the result of lack of maintenance. We recommend regular coolant changes by draining and refilling the system, and adding conditioners to keep it clean. If this is done on a regular basis, you probably will never need to flush it.

Why pay a repair shop $90.00 per hour to do this when you can do it yourself very easily. A gallon of coolant and conditioners (HIGHLY RECOMMENDED!!) will cost less than $20.00, and will help prevent cooling system and automotive thermostat failures. What happens to coolant over time from its interaction with oxygen, and other chemical contacts within the engine makes it become acidic. Since most of todays engines are comprised of mostly aluminum components, this acidity can be quite a problem.

What is the purpose of the automotive thermostat?

Due to the fact that coolant is environmentally hazardous, you must collect and properly dispose of your used coolant. DO NOT – I REPEAT – DO NOT flush with a garden hose. That will not be necessary if you drain and fill on a regular basis. If there is sludge or foreign material in your automotive cooling systems you will want to consult a professional.

The first thing to remember before any automotive repair or service is SAFETY FIRST!

Never remove the radiator cap on a hot engine, and when you do open the system always use a rag to sheild yourself from spray.

You will need a few items prior to draining and refilling your automotive cooling system.

a) Protective eyewear to prevent a splash from entering your eyes.

b) A pair of rubber gloves.

c) About three empty one gallon milk jugs for disposal.

d) A drain pan to collect the drained coolant.

e) A gallon of replacement coolant (be sure it is the correct type).

f) Conditioners to keep cooling system in shape for next six months.

Procedure to drain and refill your automotive cooling systems:

Start with a cold engine and locate the petcock on the radiator, usually on the lower section of the drivers side. Position the drain pan directly under the petcock, loosen the petcock and allow the coolant to drain out (this should take about 15 minutes before it stops dripping). Tighten the loose petcock to allow you to refill the system. Pour the used coolant into your empty milk jugs and dispose of properly. Now refill the radiator with your 50/50 coolant/water mixture, and the conditioners that I recommended.

Your automotive cooling systems are good for another six months, and you saved money on wear and tear on your automotive thermostat as well as the rest of the components in your system. You will save a substantial amount of money if you follow this practice. Automotive cooling systems need to be maintained but it isn’t very hard to do. And it will save you money — that’s the main thing!