The failure of hydraulic system is often the result of the comprehensive influence of many factors, so before analyzing the failure, it is necessary to understand the principle and characteristics of the entire hydraulic system, and then judge according to the failure phenomenon. There are both missing parts and testing instruments on the construction site. There are some tricks to find the cause of the fault. The most common method is to reverse the component and remove the load. If the component is reversed and the fault is also reversed, it proves that the component has a problem; load, the fault disappears, and the problem is understood.

　　In short, it is necessary to narrow down the scope of the fault step by step in a purposeful and directional way, to determine the fault area, location or a certain hydraulic component, and to avoid random dismantling and repairing. It is necessary to avoid the blindness of the analysis, because the oil flow in the hydraulic pipeline, the movement of the parts inside the hydraulic parts, and the damage of the seals are intangible and invisible. Statistics show that more than 70% of hydraulic system failures come directly or indirectly from improper maintenance or contamination of hydraulic oil. Therefore, it is very important to maintain the cleanliness and good maintenance of hydraulic oil.

　　Causes of common faults in the hydraulic system and simple troubleshooting methods:

　　Fault 1: Oil leakage and oil leakage in the oil circuit

　　1. Causes: (1) The hose or steel pipe burst, (2) The steel pipe is not strong, (3) The seal is damaged or not installed, (4) The joint is not tightened or loose, (5) The hydraulic joint has bump marks.

　　2. Elimination methods: (1) replace with new parts, (2) grind and repair, (3) renew and fasten.

　　Fault 2: Excessive noise

　　1. Causes: (1) The pipeline leaks, (2) The components or pipelines are not fixed well, resulting in vibration, (3) The oil level of the fuel tank is too low, (4) The speed control valve or overflow valve is unstable.

　　2. Elimination method: (1) tighten the joint or replace the seal, (2) clean or replace the valve, (3) add hydraulic oil.