Checking method for fan running and swinging: pull the fan blade back and forth by hand, and observe whether the pulley is loose. If it feels loose, first check whether the fan fastening screws and pulley fastening nuts are loose. If there is no looseness, it means that the bearing is loose, it should be disassembled and replaced, and enough grease should be added.
Check the water pump pressure on your vehicle: With the engine running, hold the hose that connects the cylinder head to the radiator water outlet. When the throttle is raised from idle speed to high speed, if the pressure rises, it means that the water pump pressure is normal; if there is no special feeling, it means that the water pump is insufficient, and the water pump should be removed for maintenance.
Check whether the pump shaft is bent, whether the wear of the journal exceeds the limit, and whether the thread at the end of the shaft is damaged. The bending of the pump shaft should not exceed 0.05mm, otherwise it should be replaced. Check the impeller for severe cavitation, corrosion or cracks. When cracks, severe cavitation and corrosion are found, they should be replaced. Impellers with slight cavitation can be repaired with glue. If scratches and uneven wear are found on the contact surface between the impeller and the water seal, replace it with a new one.
Precautions for car water pump leakage After inspection and repair, the water pump should be assembled in the reverse order of disassembly. When assembling, pay attention to the relative position of the pump body and the connecting pipe, and avoid connecting with the pipe. After the pump has been reinstalled, it should be inspected. When turning the pump shaft, it should be flexible and free from jamming. Fill the water pump with water, block the water inlet and outlet, and turn the pump shaft to prevent water leakage.