If we suddenly have a fault while driving a small loader, the quickest way is to do the diagnosis on site. Here are some tips for small loader repair?
1. First understand what abnormal phenomena exist in the small loader; whether the fault is sudden or gradual; whether there is illegal operation, maintenance and repair in use; whether the hydraulic oil grade is correct and replaced; the timing of the fault is It only appears at the beginning of the work or after a certain period of work. Once this information is available, the characteristics of the fault in the hydraulic system can be determined. In general, sudden failures are mostly caused by poorly closed valves due to excessive hydraulic oil or spring breaks; most of the failures occur due to severe component wear or rubber seals and aging of the pipe fittings.
2. Check whether the oil in the small loader tank meets the requirements, whether there are bubbles or discoloration (the noise, vibration and creep of the machine are often related to a large number of bubbles in the oil); oil leakage at the sealing part and the street of the pipe The situation; the pressure gauge and the oil temperature gauge indicate changes in the value during the work; the fault location has no damage, the connection gradually falls off and the fixing member loosens. When there is a fault in the leakage of hydraulic oil, after eliminating the insufficient or uneven torque of the forbidden bolt, check whether the pressure is over-limit before replacing the oil seal that may be seriously worn or damaged. When installing the oil seal, the type and quality of the oil seal should be checked and assembled accurately.
3. Check the pipeline or components of the hydraulic system of the small loader for vibration, shock and abnormal oil temperature rise. If you touch the pump casing or hydraulic parts by hand, you can judge whether the hydraulic system has abnormal temperature rise according to the degree of heat and cold, and determine the cause and location of the temperature rise. If the pump casing is overheated, the pump is leaking heavily or sucking in air. If the vibration is abnormal, it may be that the rotating parts are not well balanced, the fastening screws are loose, or there is gas in the system.
4. When only a certain circuit or a certain function is lost in the hydraulic system of the small loader, it can be exchanged with the same (or related) function oil circuit to further determine the fault location. If the excavator has two independent working circuits, each circuit has its own components. When one circuit fails, the other pump can be connected to the circuit by exchanging the high pressure oil pipe. If the fault is still on one side. , indicating that the fault is not on the pump, the other components of the loop should be checked; otherwise, the fault is on the pump. Another example is the travel device of an excavator. When there is a fault that one side can walk and the other side cannot walk or automatically deflect, the two newly purchased motor tubes can be reversed to determine whether the faulty part is on the motor or in the reversing valve. .