Cooling System

How an Engine Cooling System Works

Inside your car's engine, thousands of controlled explosions called combustion events caused by igniting fuel / air mixture inside the engine. Spark plugs are used to ignite the fuel / air mixture contained in the cylinders. These explosions are converted into power through the engine while producing a large amount of heat. These high temperatures are controlled with the help of the cooling system. A cooling system consists of a water pump, thermostat, radiator hose, hose clamps, radiator, radiator cap and coolant.



The engine's combustion chamber reaches up to a temperature of four thousand five hundred degrees Fahrenheit. About thirty percent of the fuel is converted into actual power, and about seventy percent is spent into heat. A cooling system protects an engine from damage by transferring heat to the atmosphere by using the radiator. A correct operating temperature is critical for the proper function of the engine. The thermostat controls when coolant is allowed to flow into the radiator and back into the engine. Manufacturers have found that a 195 degree thermostat is optimum for efficiency. Below this threshold the catalytic converter will not work to capacity and will produce increased emissions. Coolant is pumped through the engine block by the water pump where it passes into the radiator. Automatic transmission vehicles utilize a fluid cooler inside the engine coolant radiator. This cooler is use to cool the transmission fluid that has been heated from normal usage.

Engine coolant is used to transfer heat from the engine to the radiator by the cooling system. The radiator removes heat from the coolant by forcing air through the radiator fins. Without coolant your engine will over heat and if left unattended sever engine damage will occur. Coolant colors can vary from green, orange, blue and yellow each having their own protective properties. (Note: coolant and antifreeze refer to the same product, in below freezing, coolant lowers the freeze point hence the name anti-freeze and in warm weather coolant helps raise the boiling point, "coolant")

A water pump is used to circulate water throughout the engine block, cooling and heater systems. The water pump is driven by the engine via multi rib belt in most cases. When a water pump fails it can produce a squeaking or rattling sound. Also, a water pump can leak engine coolant through a relief port that allows coolant to pass when the shaft seal fails. This port is created so engine coolant will not contaminate the shaft bearings causing a worst problem. If a failing or failed water pump is allowed to operate it can cause the engine to over heat or completely fall apart causing cooling system or other sub sequential damage. The water pump circulates coolant continuously, a thermostat is used to control cooling system operation. A water pump is comprised of a main housing body, flange, main shaft, bearings, impeller, seals and a gasket to seal in against the block. When engine RPM increase so does the water pump flow rate. A water pump will typical last between 60,000 and 100,000 miles. When replacing a water pump always insist on high quality replacement parts to avoid premature failure. To check your water pump condition, make sure the engine is off, next grab a hold of water pump flange and try to move it back and forth. There should be little to no play in the main shaft bearing. If excessive play exists the water pump has failed and needs replacement.




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How Does it Work / Radiator Cooling System

* How a thermostat works?
* How to test a thermostat
* Radiator questions
* How to change a radiator
* Coolant condition information
* How does a water pump work?
* How does a clutch fan work?
* Car is making a bubbling noise
* Car is making a chirping sound
* Howling noise from car
* Why is my car making a popping noise?

How an Engine Cooling System Works

Inside your car's engine, thousands of controlled explosions called combustion events caused by igniting fuel / air mixture inside the engine. Spark plugs are used to ignite the fuel / air mixture contained in the cylinders. These explosions are converted into power through the engine while producing a large amount of heat. These high temperatures are controlled with the help of the cooling system. A cooling system consists of a water pump, thermostat, radiator hose, hose clamps, radiator, radiator cap and coolant.

Coolant System Water Pump
Typical Engine Cooling System

The engine's combustion chamber reaches up to a temperature of four thousand five hundred degrees Fahrenheit. About thirty percent of the fuel is converted into actual power, and about seventy percent is spent into heat. A cooling system protects an engine from damage by transferring heat to the atmosphere by using the radiator. A correct operating temperature is critical for the proper function of the engine. The thermostat controls when coolant is allowed to flow into the radiator and back into the engine. Manufacturers have found that a 195 degree thermostat is optimum for efficiency. Below this threshold the catalytic converter will not work to capacity and will produce increased emissions. Coolant is pumped through the engine block by the water pump where it passes into the radiator. Automatic transmission vehicles utilize a fluid cooler inside the engine coolant radiator. This cooler is use to cool the transmission fluid that has been heated from normal usage.

Engine coolant is used to transfer heat from the engine to the radiator by the cooling system. The radiator removes heat from the coolant by forcing air through the radiator fins. Without coolant your engine will over heat and if left unattended sever engine damage will occur. Coolant colors can vary from green, orange, blue and yellow each having their own protective properties. (Note: coolant and antifreeze refer to the same product, in below freezing, coolant lowers the freeze point hence the name anti-freeze and in warm weather coolant helps raise the boiling point, "coolant")

Red and Green Engine Coolant
Red and Green Engine Coolant

A water pump is used to circulate water throughout the engine block, cooling and heater systems. The water pump is driven by the engine via multi rib belt in most cases. When a water pump fails it can produce a squeaking or rattling sound. Also, a water pump can leak engine coolant through a relief port that allows coolant to pass when the shaft seal fails. This port is created so engine coolant will not contaminate the shaft bearings causing a worst problem. If a failing or failed water pump is allowed to operate it can cause the engine to over heat or completely fall apart causing cooling system or other sub sequential damage. The water pump circulates coolant continuously, a thermostat is used to control cooling system operation. A water pump is comprised of a main housing body, flange, main shaft, bearings, impeller, seals and a gasket to seal in against the block. When engine RPM increase so does the water pump flow rate. A water pump will typical last between 60,000 and 100,000 miles. When replacing a water pump always insist on high quality replacement parts to avoid premature failure. To check your water pump condition, make sure the engine is off, next grab a hold of water pump flange and try to move it back and forth. There should be little to no play in the main shaft bearing. If excessive play exists the water pump has failed and needs replacement.

Car Water Pump
Water Pump (appearance will very)

In the beginning, water was used for cooling systems as it is the most efficient fluid to absorb and dissipate heat. The disadvantage of using water is that it freezes and will rust. Then water was mixed with ethylene glycol which worked as an antifreeze element. Not only does the freezing point improve so does the boiling point by adding ethylene glycol. Ethylene glycol can be heated up to 250�F before becoming ineffective. The cooling system is pressurized to 18 psi. to increase coolant boiling point which adds 9 degrees Fahrenheit to the boiling point of the coolant. Coolant is also used to avoid corrosion. An engine thermostat is designed to stop the flow of coolant from the engine to the radiator. This temperature sensitive valve is designed to open when the engine has reached operation temperature (190�-198� F). The operating temperature of 190�-210� F. which is used to help facilitate fuel combustion. When a thermostat fails it will either stop the coolant flow at operating temperature "stick closed" or fail to stop the coolant flow causing the engine to run colder longer than necessary. If the thermostat fails "open" it will cause the coolant to continuously flow through the engine creating a diagnostic trouble code (check engine light) will be set. When a thermostat sticks it will cause the engine to overheat quickly, usually within 5 to 15 minutes of operation. To check for either of these conditions drain coolant and remove thermostat, (under the thermostat housing) if you are unsure of the location of the thermostat on your engine consult a car repair manual. Once you have removed the thermostat inspect the condition of the main body check for any cranks or broken pieces and check the valve to make sure it is closed. If the valve is open the thermostat has failed and needs to be replaced. To check the operation of the thermostat prepare a pot of water on the stove deep enough to cover the thermostat completely. Place the thermostat in the pot of water, turn the stove on a medium/high flame, the thermostat should open right before the water comes to a boil. If the water has boiled and the thermostat valve is still closed the thermostat has failed and needs to be placed.