1. Priority thought was "Waterproof Cooling Fan" No motor lubrication, shaft portion to be lubricated, yesterday I was in this case, the fan is mounted on top of the motor can not drag, but after I removed, the shaft can operate normally, indicating that the motor no broken. How to judge the lack of oil out? After the power is off, you gently struck fan, found the rotation a little stiff, indicating that the oil is gone, but it is very easy to turn freely, indicating oiled, this is another reason not to turn up.
2. Second, you have to consider "Waterproof Cooling Fan" with how long, the motor loss, after the motor bushings wear, it is easy to burn. Motor with a long time, it will also make the motor resistance becomes larger, with a load capacity is low, making it impossible to drive the blades rotate.
3. "Waterproof Cooling Fan" motor overheating can cause deterioration of the motor with a load capacity, low active power of the motor, making it impossible to drive the load.