What is the reason for the leakage of antifreeze in the water tank?

Coolant is a kind of liquid with antifreeze function, and its full name should be called antifreeze. It can prevent the radiator and engine from expanding and damaging the cylinder block due to the freezing of coolant when parking in cold season. However, there is a common misunderstanding that needs to be corrected: antifreeze is not only suitable for winter, but also for the whole year. Generally speaking, antifreeze is stored in the oil tank, but this may be because your oil tank is broken. There are several reasons for the decrease of automobile coolant: 1. Under normal circumstances, the liquid level of the coolant tank should remain basically unchanged. It has been in operation for several years, which should include checking the leakage problem every time. The method of inspection is actually very simple. First, see if there is a watermark of antifreeze in the parking space corresponding to the ground and the fuel tank. Then look up from the front lower part of the car. If there is water mark on the lower part of the oil tank or pipeline, it means there is leakage and needs to be checked. 2. Loud fan sound is also related to the fuel tank temperature. When the temperature of the water tank exceeds a certain temperature, the fan starts to work. If the temperature of the water tank is not high, the fan does not need to reduce the working sound. 3. If the water leakage can be eliminated, it may be that the antifreeze used in the 4S shop is diluted too much and the content is insufficient. The concentration of antifreeze must be increased. The best ratio is half antifreeze and half water, and it can be used for a long time without antifreeze (1-2 years or more). It is obviously not enough for 4.4S stores to only have 10% or 20% antifreeze. Their purpose may be to earn more maintenance fees.