During the daily maintenance of excavator rental, the problem of replacing hydraulic oil is occasionally encountered. Replacing hydraulic oil is not simple, and a certain method needs to be mastered. The following is a brief introduction of the preparation for the replacement of hydraulic oil.
1. Purchase oil for hydraulic system of vehicle. (Hydraulic tank volume 2. Five times), filter element, washing oil, 3kg flour, rope, oil plug of closed hydraulic tubing, a steam pump and empty oil barrel of size, etc. Prepare a normal excavator. Lift the arm of the oil-changing excavator to the highest point, and the engine will be extinguished when the bucket bar and bucket receive the interior point (all the cylinder bars of the boom cylinder, bucket cylinder and bucket cylinder reach the apex).
2. Hydraulic tank cleaning: all the hydraulic oil in the tank is discharged, the hydraulic filter element is withdrawn, and the pipeline between the pump and the tank is dismantled from the interface of the pump, and the oil in the pipeline is discharged. Flush the hydraulic tank and pipeline with washing oil. Clean the inside of the hydraulic tank with medical sandcloth. The flour is kneaded and stretched into three parts. The inside of the hydraulic tank, especially the corners of the tank and the filter cartridge, is cleaned three times with the dough.
Occasionally, in the course of daily operation, the slow movement of the elongated arm of excavator occurs. What is the reason for this situation? We can consider it from the following aspects.
1. The upper arm and the lower arm can not lift and extend. This fault is basically caused by the damage of crankshaft sensor of the upper arm and the lower arm. This sensor functions as a common potentiometer to sense the angle of the working arm and prevent overoperation from overturning or collision.
2. If the sensor fails or the line is short-circuited, the above-mentioned failures will occur. The sensor is not easy to purchase. The solution is to replace the sensor with two resistors, which can also make the excavator work normally, but will lose the protection function.