What kind of water should be added to a water-cooled engine?
3 Answers
Water-cooled engines require antifreeze coolant, not tap water or mineral water. The reasons are as follows: 1. Reason one: Using tap water or mineral water can easily cause scale buildup and rust in the radiator and engine cooling system. 2. Reason two: Antifreeze coolant has higher boiling and freezing points compared to water, which cannot meet the operational requirements of automobiles. Relevant information about antifreeze coolant is as follows: 1. Antifreeze coolant (antifreeze) prevents the coolant from freezing during cold winter parking, which could otherwise crack the radiator and damage the engine cylinder block. Its full name is antifreeze coolant. 2. Chemical composition: Over 95% of antifreeze coolants used domestically and internationally are ethylene glycol-based aqueous solutions. Compared to tap water, ethylene glycol's most notable characteristic is its antifreeze property, whereas water cannot prevent freezing. Additionally, ethylene glycol has a high boiling point, low volatility, moderate viscosity that changes little with temperature, and good thermal stability. Therefore, ethylene glycol-based antifreeze coolant is an ideal cooling solution.
The first time I heard about water-cooled engines, I thought you could just add tap water directly, as simple as watering plants. Later, I realized how wrong I was! A friend told me that the engine cooling system must be filled with specialized antifreeze coolant, not ordinary water. Adding pure water can cause rust and corrosion inside the engine, and in winter, it can freeze, expand, and damage components. I rushed to an auto shop and bought a bottle of green antifreeze, pouring it directly into the radiator while making sure the fluid level wasn’t too high. Remember to check the fluid level regularly—if the color fades, it’s time for a replacement, typically every two years. Doing this ensures the engine runs efficiently and avoids overheating issues. Safety first—don’t cut corners by using water, as repairs from damage will be far more troublesome.
I love tinkering with cars and have tried adding water to the coolant reservoir a few times, with disastrous results. Pure water can corrode radiators and pipes, leading to leaks and part replacements over time. It's best to use a dedicated ethylene glycol-based coolant, which prevents freezing, boiling, and corrosion. I usually opt for a 50% pre-mixed ratio and pour it directly into the reservoir without diluting. In emergencies, a small amount of distilled water can be added temporarily, but it's crucial to switch back to the proper coolant as soon as possible. Coolant also has a lubricating effect, making the water pump more durable. When maintaining your car, always check that the reservoir cap is tightly sealed to prevent air from entering and affecting cooling efficiency.
