The failure phenomenon of the excavator walking has no idle speed: after 8000 hours of the work of a Hyundai excavator, there is no automatic idle speed fault for 8000 hours. When the automatic idle speed function is opened, the speed of the engine can not be raised from the idle to the target speed.
The possible reasons for the failure are: failure of running automatic idle speed pressure switch, obstruction of running pilot pressure orifice, failure of main control unit (CPU), failure of instrument panel or wiring harness.
The failure steps and reasons of Hyundai R225LC-7 type excavator walking without automatic idle speed are analyzed.
There is no change in the CO 6 and CO 7 harness to the debugger, indicating that the main control unit (CpU) and the wiring harness have no problem; the automatic idle speed is controlled by the instrument, and the automatic idle speed of the working device can be controlled, indicating that the dashboard is normal; the SW of the downlink pressure switch is 1, and the pressure meter is connected at the A point to move around. It is found that the pressure (normally close to or equal to the pilot pressure) is close to zero when it is done. The analysis considers that the fault is at the throttle hole or the oil filter. Remove the side throttle hole of the main control valve, find the throttle hole to be blocked. The test machine is normal by using compressed air to blow through the hole (07mm) and cleaning the oil filter. The main cause of the failure is the hydraulic system. The maintenance is not carried out according to the relevant regulations of the manufacturer. Because the maintenance time of the filter element is prolonged, the oil is polluted, resulting in failure.
In Leshan Jingyan County, a small wharf is about to be built on the riverside of the Yangtze River, which is mainly used for transportation of sand. The current work of the Hyundai R225LC-7 excavator is to build a gate for the wharf, which is 100 meters long, 2 and 30 meters wide, mainly for drainage. When the water is rising, the gate is opened and the water can be drained into the other side of the gate. In this way, the embankment was strengthened to prevent the dikes from being washed out by the river. They built a body shield for the dam. Although the Hyundai R225LC-7 type excavator appeared during the operation, the excavator walked without automatic idling and delayed the project progress, but immediately after the failure, it was put into the construction of the gate as maintenance. I am very proud of the maintenance staff.
