Car Engine Coolant
Car engine coolant is essential for the proper operation of every internal combustion engine. Hundreds of small explosions are created every second inside the cylinders as the spark plugs ignite the fuel and air mixture. The tremendous amount of heat generated needs to be removed to protect the other engine parts from being damaged by overheating. This is done by cycling the coolant between the engine and the radiator, where the heat is removed. Coolant is mostly water mixed with antifreeze, with a small amount of corrosion inhibitor. The two main types of antifreeze are ethylene glycol and propylene glycol.
The cooling system used in most cars is comprised of a radiator, pump, reservoir, coolant and pipes. A complex network of tiny channels inside the engine allows the coolant to absorb heat from the surrounding metal. The coolant is moved around the pipes and channels by the pump, which is turned by a drive belt connected to the crankshaft. The coolant is pumped to the radiator where the heat is released to the outside air, before returning to the engine. The reservoir allows the level of coolant to be checked and topped up when necessary.
Water is the most basic type of car engine coolant, but plain water should never be used in cold climates. Water expands when it freezes and this could easily crack the metal pipes and joints in the cooling system. Antifreeze substantially lowers the freezing point of water and also raises its boiling point slightly. Ethylene glycol is the most widely used antifreeze but it is also toxic and can be fatal if swallowed. Propylene glycol is often called non-toxic antifreeze because it is far less toxic than ethylene glycol. All coolants should be kept out of reach of children because the antifreeze has a sweet taste and could be mistaken for soft drink.
Corrosion inhibitors are also added to car engine coolant to protect the engine, radiator and other metal parts. Inhibitors are chemical compounds that bond to the metalwork and reduce the rate of decay. Dye is also added to the coolant for identification and safety purposes. Both types of antifreeze are colorless which makes it difficult to tell them apart from plain water, so the dye helps prevent illness from accidental consumption. Coolant is usually dyed green or red but some brands use a unique color for marketing purposes.
Car engine coolant needs to be changed every two years to ensure that it will protect the engine. Changing the coolant is a simple and inexpensive task that can be done at home by most people. The additives in coolant are toxic so contact with the skin and clothing should be avoided. Seek immediate medical help if coolant is ingested. Coolant should not be disposed of in the garden or poured down the drain. Instead, place it in a sealed container and take it to a waste disposal facility. Many service stations also take waste coolant, as well as engine oil and old batteries.
Changing the car engine coolant is a simple but messy task that takes about half an hour. Wait until the engine is cold and then open the radiator cap. Place a large container under the radiator and open the drain plug to allow the coolant to flow out. Flush the rest of the coolant out by filling the system with plain water and running the engine for a few minutes, making sure to first replace the cap and drain plug. Drain this water out and replace the drain plug, then fill the radiator with new coolant. Most cars use a mixture of half coolant and half water, but those in very cold climates need more coolant than water.
