After the hydraulic pump is installed, it must be filled with clean hydraulic oil through the oil drain port on the tie shell before starting for the first time, otherwise it cannot be started. After installing the hydraulic pump and motor and connecting the system correctly, inject clean oil into the pump or motor, remove the upper drain pipe, and tighten the joint after seeing the oil flow out. The starting of the hydraulic pump has the following contraindications:

1. Rotate the coupling by hand to check the state of the pump shaft. It is forbidden to have uneven force during rotation, loose installation, and two couplings with different shafts.

2. It is forbidden that the rotation direction of the pump motor does not match the specified rotation direction. For hydraulic pumps with reversible oil flow (such as servo variable pumps), it is also necessary to check whether the indication direction of the dial is consistent with the direction of the oil inlet and outlet (when the oil inlet and outlet are as indicated on the pump, the pointer should be on the scale. the forward direction of the disk, and vice versa).

3. There should be an empty load circulation circuit in the hydraulic system. It is forbidden to start or stop the hydraulic pump at full load, otherwise the service life of the hydraulic pump will be reduced and the motor will be overloaded. The adjustment pressure of the relief valve in the hydraulic system should not be greater than 35.0MPa.

4. When the hydraulic pump is started, it is forbidden to start once and then run continuously. The start button should be turned on and off several times to confirm that the oil flow direction is correct and the sound of the hydraulic pump is normal before running continuously.

5. When starting the engine, make sure that the hydraulic pump control handle is in the neutral position, and it is forbidden for the engine to enter the working state immediately. The engine should be idled for 3 to 5 minutes before entering the working state.

6. It is forbidden to start the hydraulic pump for the first time. There is no discharge path for the air in the hydraulic pump. For some hydraulic pumps, such as vane pumps for vehicles, due to the large internal leakage of the pump, it is difficult to discharge the air in the system when the pump is started for the first time, resulting in poor suction of the hydraulic pump. This is even more the case with the valve. Change the Y-Cui reversing valve to an M-type reversing valve that can discharge air from the outlet of the hydraulic pump. Of course, it can also be solved by loosening the relevant joint of the hydraulic pump outlet.

7. The starting of the hydraulic pump with load means that at the moment of starting, the rotor of the hydraulic pump changes from static to rotating. At the same time, the pressure of its suction chamber drops, and its discharge chamber must establish a pressure corresponding to the load. This state is quite unfavorable to the hydraulic pump, especially the plunger pump, which often leads to the damage of the hydraulic pump. When starting with load is unavoidable, corresponding measures should be taken. In some hydraulic systems, it is unavoidable to start the hydraulic pump with load. In this case, corresponding measures should be taken. For example, by properly designing the hydraulic circuit, the pump can be started with another non-loaded hydraulic pump before starting. The corresponding differential pressure is established to balance the external load before starting the pump. And after the hydraulic pump starts and runs normally, the working pressure of the pump started without load is smoothly transitioned to the pump.