For small forklifts, the hydraulic oil should be changed every 2000 working hours or once a year. Because hydraulic oil may be at high temperature when changing oil, please wear protective equipment and handle it carefully to avoid personal injury. The method of replacing hydraulic oil is as follows: \x0d\ 1. Clean up the sundries in the bucket, park the machine in a flat and empty place, put the speed change control handle in neutral position, pull up the parking brake valve button, and install the frame fixed bumper. Start the engine and run at idle speed for 10 minute, during which actions such as lifting the boom, lowering the boom, tilting the bucket forward and tilting the bucket backward are repeated many times. \x0d\2。 Finally, lift the boom to the highest position, tilt the bucket back to the maximum position, and then stop the engine. \x0d\3。 Push back the operating handle of the pilot control valve bucket, so that the bucket rotates forward under its own weight, and the oil in the bucket cylinder is discharged; After the bucket rotates in place, push the control lever of the boom of the pilot valve forward, and the boom will descend under its own weight to discharge the oil in the boom cylinder. \x0d\4。 Turn the pilot oil shutoff solenoid valve switch to the "OFF" position. \x0d\5。 Clean the oil drain below the hydraulic oil tank, unscrew the oil plug, drain the hydraulic oil and fill it with a container. At the same time, unscrew the filler cap to speed up the oil discharge process. \x0d\6。 Remove the oil inlet pipe of the hydraulic oil radiator and drain the residual hydraulic oil in the radiator. \x0d\7。 Remove the top cover of the hydraulic oil return filter from the hydraulic oil tank, take out the oil return filter element and replace it with a new one. Open the filler cap and take out the filler screen for cleaning. \x0d\8。 Take down flange cover, the cleaning port of the oil tank below the oil filler, wash the bottom and wall of the hydraulic oil tank with diesel oil, and finally dry it with a clean cloth. \x0d\9。 Install the oil drain plug of hydraulic oil tank, oil return filter and top cover, oil filler screen, oil tank cleaning port flange cover and oil inlet pipe of hydraulic oil radiator. \x0d\ 10。 Remove the oil return pipe on the hydraulic oil radiator and add clean hydraulic oil from the oil return port of the hydraulic oil radiator. After topping up, install the oil return pipe of hydraulic oil radiator. \x0d\ 1 1。 Inject clean hydraulic oil from the oil filler of the hydraulic oil tank to make the oil level reach the upper scale of the hydraulic oil level gauge, and tighten the oil filler cap.