What is the composition of antifreeze?
4 Answers
The main components of antifreeze are 50% pure water, 40% methanol, and 10% other substances. Types of antifreeze: Antifreeze is generally divided into three types: ethanol-water type, glycerol-water type, and ethylene glycol-water type. How to choose antifreeze: The basic indicators of antifreeze are the freezing point and boiling point. The freezing points of antifreeze available in the market include -15°C, -25°C, -30°C, -40°C, etc. Generally, it is advisable to choose an antifreeze with a freezing point at least 10°C lower than the lowest temperature in your region. How to replace antifreeze: Before completely replacing the antifreeze, conduct a thorough inspection to check for any signs of leakage or cracks in the pipelines, with a focus on the five-way water pipe. The five-way pipe gets its name from having five connecting interfaces to various parts. Antifreeze flows through the five-way pipe and is then distributed to different parts of the car to function. If there is any leakage of antifreeze in this part, the water pipe should be replaced or the interface should be re-secured as needed. Drain the old antifreeze, then flush the liquid channels with clean water. Add clean water to the antifreeze reservoir and continue to pour water into the reservoir, allowing the water to continuously circulate through the engine cooling system. Then, start the engine and let it idle for 3 to 5 minutes to circulate the water. The water initially flowing out of the reservoir will be slightly pinkish. Continue adding clean water until the water flowing out is clear. Note: Remember to remove the heater hose and drain the water from the heater. After draining for about an hour, add the new antifreeze through the radiator hose, which allows the antifreeze to flow quickly into the radiator. Then, add another bottle of antifreeze to the antifreeze reservoir until it is nearly full. Start the engine and let it run for about 10 minutes. At this point, the coolant level will drop slightly as some air is expelled from the cooling system. Add more antifreeze until it reaches the "MAXT" mark on the reservoir.
The main components of antifreeze are ethylene glycol and water, which are used in most vehicles. Ethylene glycol is used to lower the freezing point, preventing the coolant from freezing, so you don't have to worry about engine damage in winter. Additives are also mixed into the water, such as corrosion inhibitors to prevent metal rusting and antifoaming agents to avoid bubbles affecting heat dissipation. Some brands use propylene glycol instead of ethylene glycol, which is less toxic. Additives also include pH stabilizers to ensure the liquid does not deteriorate. I always check this before autumn and winter. The typical ratio is 50% ethylene glycol and 50% water, which provides a low enough freezing point and high thermal efficiency. When purchasing, check the packaging instructions to ensure the freezing point suits your local weather. Maintenance is simple—replace it every two years to avoid failure and protect the engine.
I understand that the core components of antifreeze are base fluids such as ethylene glycol or propylene glycol, mixed with deionized water and various additives. Ethylene glycol-based antifreeze is cost-effective, while propylene glycol is more environmentally friendly and non-toxic. Among the additives, corrosion inhibitors protect the radiator and engine from rust, and pH regulators maintain liquid stability to prevent system corrosion. The mixing ratio is crucial—when I do DIY car repairs, I often use a test strip to measure concentration. If it's too concentrated, heat transfer efficiency decreases; if it's too diluted, the freezing point won't be sufficient. Additives also include anti-foaming agents to prevent cooling issues, and some contain fluorescent dyes to help detect minor leaks. Regular replacement is recommended to maintain performance, as additives degrade over time and lose effectiveness.
Antifreeze typically contains ethylene glycol as the main component, but leaks can contaminate water sources or harm plants and animals. I prefer environmentally friendly options, such as propylene glycol-based ones, which decompose faster and are safer. Among the additives, corrosion inhibitors prevent rust, but it's essential to choose phosphate-free ones to reduce water pollution. When using, pay attention to the ingredient labels to avoid highly toxic additives. For daily disposal of old fluid, take it to a recycling station; pouring it down the drain is harmful to the ecosystem. During replacement, minimize leakage to protect the environment.
