1. First check whether the adjusting rod nut on the drain valve is loose, whether the tractor cable is loose with the drain valve, and the tractor cannot pull the drain valve core to cause undraining.
2. If the fixing nut is not loose or the cable is not loose, the tractor may be damaged and the drain valve core cannot be opened. The tractor should be replaced at this time.
3. There may be a blockage of debris in the drain valve or a deformation of the drain hose. At this time, first unscrew the drain valve cover and remove the debris.
4. The gap between the drain rod and the rubber valve becomes larger, as long as the gap between the drain rod and the rubber valve is properly adjusted.
5. The spring inside the drain valve is too long or loses its elasticity. Just replace the inner spring.
6. The drainage solenoid valve has too much damping or a small suction force. Remove rust from the electromagnet or replace the drain solenoid valve.