What is Coolant?
2 Answers
Coolant, fully known as antifreeze coolant, refers to a cooling liquid with antifreeze properties. Its function is to carry away the heat from the engine through circulation, helping to maintain the engine temperature at around 90 degrees Celsius. This ensures high thermal efficiency, smooth operation, and strong power output from the engine. Since coolant remains in liquid form during winter without freezing, it prevents the backflow and freezing of engine condensate, thereby protecting the engine and its pipelines. Hence, it is also called antifreeze. The functions of coolant include corrosion prevention, cavitation and leakage prevention, radiator boil-over prevention, scale prevention, and freeze protection, ensuring the cooling system remains in optimal working condition and maintaining the engine's normal operating temperature.
I remember my first coolant change was when I was an apprentice at the auto repair shop. The master pointed at that bucket of pink liquid and said, 'This is the engine's fever reducer!' It's actually just a mixture of water and ethylene glycol, preventing freezing in winter and boiling in summer. Once, a customer's radiator boiled over, and when we opened the engine, the water channels were full of rust—this is what happens when you use tap water. Nowadays, the green, blue, and red liquids sold in supermarkets differ in their additive formulas, with the organic acid type being the most corrosion-resistant. Remember to change it every two years or 40,000 kilometers, or else you might end up like my old Jetta, which blew a head gasket and cost over 3,000 yuan to fix. When washing the car, take a quick glance at the auxiliary tank's level line—if it's low, top it up with the same color liquid, as mixing can cause crystallization.
