1. The digger moves right and the bucket does not move, the moving arm and the bucket pole move slowly.
According to the response of the owner of the excavator, after replacing the seal of the control valve assembly, the defect appears. After measurement, the pressure of the pump bucket is 1.5 Mpa, which is much lower than the normal value of 28.5 Mpa.
When preparing for two-way AC valves, it was found that there was a plug on the wrong side of the valve orientation, while the original plug orientation was installed with a valve. The machine is normal after correctly communicating with each other. After the original repairman replaced the seal of the control valve assembly, the valve and the plug position of the group of valves were reversed.
2. After refitting the excavator to lengthen the arm, the whole vehicle is slow and weak.
The pilot pump oil seal has just been replaced by the host, but it has been working normally for ten minutes after the replacement, and then suddenly it will not work. According to this situation, the lack of pilot pressure is the primary question.
After testing, the pilot pressure is very low and the pilot pump is decided to differentiate.
It is found that the skeleton oil seal of the input shaft of the pilot pump has been extruded. There are two reasons for this: one is the installation problem, the other is that the pressure is too high.
Continuous differentiation found that the oil seal direction of the pilot pump is reversed. This is the reason for the trouble. When the skeleton oil seal is first working, it is not completely damaged, but it can still work normally. Because the skeleton oil seal can only accept low pressure, the oil seal is quickly damaged, resulting in the leakage of the pilot pressure oil from the damaged place.
3. After refitting the excavator to lengthen the arm, the piston rod of the bucket rod cylinder retracts actively after the engine starts, and other actions are normal.
After checking, one other action is normal; the bucket rod sinks faster after the second lifting starting arm. The fault of AC bucket rod is still the same after catheterization. It is stated that the fault is in the control valve or bucket rod cylinder, based on the principle of easy first and difficult later.
The control valve stem was disassembled and checked. It was found that the valve stem was stuck in the retracted position of the piston rod. The valve stem was removed after being stirred by a rubber Hydra head and a copper rod. It can be seen that there are shining iron poles, the connection bucket rod sinks faster. The root cause of the defect was the pull of the cylinder of the extended arm bucket rod, which was confirmed after the bucket rod cylinder was dismantled and inspected.
The above news is that our long arm excavator is organized and released. We hope to help you with our website: http://www.rbaras.com!