Reasons for Air Always Present in the Radiator?

[ElisaLee]

This situation may occur due to cracks in the engine's cylinder block or cylinder head gasket, which can allow high-pressure gases from the engine to enter the coolant, resulting in air in the radiator. The car's engine is water-cooled, and the water-cooled engine relies on the continuous circulation of coolant for heat dissipation. More related information is as follows: 1. The coolant has two circulation paths within the engine: one is the major circulation, and the other is the minor circulation. When the engine is just started, the temperature is relatively low, and the coolant undergoes minor circulation. During minor circulation, the coolant does not pass through the engine's radiator for heat dissipation, which helps the engine warm up quickly. 2. The coolant needs to be replaced regularly. If not replaced for a long time, the freezing point of the coolant may rise, and the boiling point may decrease, which can affect the normal operation of the engine.