The Ins And Outs of an Engine Cooling System

Matt SomersStarred Page By Matt Somers, 5th Jun 2013 | Follow this author | RSS Feed
Posted in Wikinut>Guides>Transport>Repair and Maintenance>Cars

How the car's engine is kept cool, helping your vehicle to last longer, drive smoother, and emit less pollutant fumes.

How an Engine's Cooling System Works

Engines have been vastly improved in terms of producing less heat while providing more power, but they still require a separate cooling system to keep them operating at peak performance. Only 70% of the fuel in your vehicle is converted to mechanical energy; the remaining 30% becomes heat.

Your car cooling system does more than transfer the engine’s heat to the air. A car engine actually performs at its best at a relatively high temperature. When the engine and its parts are cold, components wear out faster, making the engine less efficient and thereby creating more pollutant fumes from your exhaust. The cooling system needs to be able to cool the engine enough, and maintain it at a constant temperature.

Each engine has a particular prime temperature when the combustion chamber is hot enough to vaporize fuel. Better engine combustion reduces emissions. At 200 degrees Fahrenheit, or about 93 degrees Celsius, the engine oil is at a desirably thin consistency, meaning it provides better lubrication for the engine’s moving pistons. This can extend their lifespan.

Engine cooling techniques

There are two types of engine cooling techniques – “air” and “liquid”.

The air cooling method, which is used mostly in older models, uses aluminium fins attached to the engine to dissipate and conduct heat away from the cylinder, aided by the directional force and added cooling of a powerful fan.

Liquid Cooling Method

The liquid cooling method is more common in modern cars. It’s also used in trains, aircrafts and even in energy-generating plants. It involves using an engine coolant, which may be either oil- or water-based, to transfer heat away from the engine. The coolant is circulated through pipes and passageways that surround the engine. On its trip around the engine, it absorbs the heat from the engine, as opposed to simply being heated and leaving the engine at the same temperature. It’s then sent to the radiator, or “heat exchange”, where it’s cooled before being re-circulated around the engine.

There is another type of engine cooling technique that is used only by high-efficiency engines known as adiabatic. In this method, the engine simply cools via accidental heat loss from the engine to the atmosphere or to other parts around it.

The thermostat

The radiator and cooling liquid don’t achieve the job of cooling on their own though. A wax-pellet type thermostat controls a valve to manage the engine’s temperature. This valve begins to open as the car reaches its optimum performance temperature. It will open as wide as possible to let out excess heat when the engine is under extreme strain – for example, if you’re driving slowly up a steep hill on a hot day and with a heavy load. Under such conditions the engine is at almost maximum output with little to no natural airflow coming into the car.

Prolonging the life of your car

If you keep a close eye on the fan, thermostat, radiator and pressure-release valve, and keep your engine cooling liquid topped up, your car will drive smoother, be better for the environment, and go for a lot longer.


Engine Coolant, Engine Parts, Radiator

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author avatar Matt Somers
I love reading and writing about different topics. I'm interested in anything to do with art, history, travel and sports.

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author avatar Johnny Knox
5th Oct 2013 (#)

Very interesting article and some valuable advice.

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