The water tank of Changan pickup truck is located on the left side of the engine. The method of exhausting the fuel tank is as follows: after replacing the coolant, set the ignition switch to the 2nd position; turn on the vehicle heater and adjust the temperature to the highest level; then maximize the air volume and step on the accelerator for 15 seconds to start exhausting. The coolant replacement process is divided into the following steps: 1. Fasten the water tank cover, remove the water tank water pipe, and release the coolant. 2. Insert the rubber tube connecting the water pipe into the water inlet of the water tank, open the tap, and allow tap water to continuously flow through the engine cooling system. 3. During the flushing operation, the engine needs to be idle and the above operation is maintained until water comes out of the water tank. Turn off the tap, wait until there is no water in the cooling system, and then close the water tank drain valve. 4. Pour coolant from the water inlet of the water tank and fill the water tank with coolant. Loosen the fuel tank cap and add coolant to the "Max" mark. Please be careful not to exceed this line, close the box lid and cover, and then tighten them. 5. Start the engine, rotate at idle speed for 2 to 3 minutes, and then twist the box cover. At this time, the cooling system has eliminated part of the air and the coolant level will drop. Please replenish the coolant until it reaches the "Max" scale. Finally, close the fuel tank cap.