Coolant, or Antifreeze is typically a 50/50 mixture of water and glycol. The glycol acts as the antifreeze agent and the coolant, keeping the water inside of the radiator from freezing in extreme cold and from boiling over during routine driving. While water is a better heat transferer, the addition of glycol allows the cooling system to maintain a stable level of heat during all driving and weather conditions.
There are only two types of consumer coolants. Separated by the type of glycol used.
Ethylene Glycol, until recently the standard antifreeze. A green toxic liquid that has been reported to cause birth defects, reproductive damage and even death if consumed. Ethylene glycol antifreeeze has a sweet smell and taste with makes it very appealing to animals and small children, and can be fatal if consumed.
Propylene Glycol, A significantly less toxic antifreeze. Very little separates these two in performance, Propylene Glycol is just less toxic, not that small animals and people should consume it, but like alcohol, small doses can be ingested without causeing harm.
Coolant levels should be checked at least once a month. To check them look at your overflow tank under the hood, there are indicators on the side of the tank that show safe levels when cold or hot. If levels are low add coolant to the fill line depending on whether your engine is cold or hot. Make sure to read your owners manual and check which anti-freeze is already in your engine. Green and orange antifreeze do not mix and can cause damage to your engine and it’s cooling system. Some vehicles over flow tanks are pressurized along with the radiator and these can be dangerous to remove while hot. Again check your owners manual to confirm if it’s safe to add coolant while the engine is hot.
Just like every thing else with your vehicle, coolant maintenance is a must. The fluid needs to be checked on a regular basis, at least once a month. Most cars have overflow or recovery tanks that are built in to the coolant system so you can easily see and add to the coolant levels. Remember to only ever add the same type of coolant. Green and Orange coolants to not mix.
Special care must be taken when disposing of anti-freeze because of it’s toxicity. Local autoparts store may provide a disposal service as well as other waste management companies around town. Radiator specific repair facilities are best equiped to handle the waste, and if you’re not a home maintenance repair type, letting a professional flush your coolant might be a better move. Never pour coolant down your sink drain or in the lawn. Always handle it with care.