What is the normal range for antifreeze loss?
2 Answers
Antifreeze loss of approximately 10% to 36% is considered normal. Antifreeze, whose full name is antifreeze coolant, is a type of coolant containing special additives. It is primarily used in liquid-cooled engine cooling systems and contains substances such as calcium chloride, methanol, ethanol, ethylene glycol, and glycerin. The functions of antifreeze include: 1. Corrosion prevention; 2. High boiling point; 3. Scale prevention; 4. Freeze protection. The method for replacing antifreeze is as follows: 1. After the engine has cooled, open the car's engine hood; 2. Open the antifreeze reservoir cap; 3. Lift the vehicle and open the radiator drain plug, drain the old antifreeze, then reinstall the drain plug; 4. Lower the vehicle and pour new antifreeze into the antifreeze reservoir.
I've been driving my old Passat for seven or eight years, so I've got some real experience with coolant issues. Normally, it's reasonable to see about half a centimeter of consumption within the marked range every three to five thousand kilometers, especially with the obvious thermal expansion and contraction in summer and winter. But if you top it up and it drops significantly within a month or so, there are basically three possibilities: either the seal on the radiator cap is aging and leaking—check the pipe connections for wet, crystallized residue; or the heater core is leaking internally—watch for pinkish stains on the floor mats; the worst-case scenario is a blown head gasket, which will cause white smoke from the exhaust. Last time, I saw a BMW owner push it until the engine seized, and the repair cost hurt more than replacing ten bottles of coolant.
