Clean the radiator in the washing pool and remove it. Wash and dry the external dirt with clean water and compressed air, and place it in a place containing 10% caustic soda? In a 15% (mass fraction) water solution container, heat it at 80~90t, let the radiator soak for about 30min, take it out and put it into a clean water tank for cleaning.

　　Check for radiator leakage by installing a radiator detector on the radiator cap and applying a pressure of 120~180kPa to the radiator to check for coolant leakage. If there is leakage, it must be repaired.

　　Check the radiator cap and exhaust valve. Install the radiator detector on the radiator cap or drain cap, and pump the pressure detector until the exhaust valve opens. Check its sealing performance and the opening pressure of the exhaust valve. When the standard value is 75~105kPa, the valve should be in an open state. When the pressure on the cover is below the limit value of 60kPa, the pressure should not drop sharply. If the limit value is not met, replace the cover.

　　Check the quality of the coolant by touching the coolant in the radiator with your fingers to check the oil content and scale layer in the coolant.