1. It is normal when the engine is cold, but it is slow when the engine is hot, and the digging is weak
The internal parts of excavator hydraulic pump are seriously worn. If it is used continuously, it is likely to lead to serious damage and failure of hydraulic pump, which indicates that the hydraulic pump has reached the degree that most areas need to be repaired. All worn parts in the pump must be replaced, and then the standard condition of hydraulic pump can be restored only after it is reassembled and debugged on the imported calibration bench.
2. The operation valve is not stable
When the guide rod and the valve stem fail to move, they need to be cleaned or grinded with abrasive for several times, but the maximum fit clearance between the valve stem and the valve body is 0.015mm. When the spring or other parts are damaged, they should be replaced with new spare parts, but they should be washed with gasoline and filled with lubricating oil before assembly.
3. After the control valve is opened, the valve stem is stuck
When dirt is mixed between the valve stem and the valve body, it is easy to cause the valve stem to be stuck. Pull the handle back and forth, and replace the control valve if necessary. This fault is very likely to cause an accident, because the handle has been pulled to the off position, but the control mechanism has not been disengaged. If the boom is lifted, it will turn over behind the excavator. At this time, the main clutch must be immediately disengaged, the power must be cut off, and the brake must be used.
