Check the hydraulic system to see if the solenoid valve have to be cleaned, and whether the regulating valve is blocked. Generally, the hydraulic pressure is lowered by its own weight, and the speed is controlled by the flow regulating valve.
It may also be due to the intake of air in the oil cylinder, so why the oil cylinder does not work due to air intake ? In fact, it is very simple. Everyone knows that the hydraulic oil cylinder is piston type. When the cylinder is air intake, the gas will run along the inner wall of the cylinder, through the oil seal to the other end of the cylinder. There is space in the cylinder, and the hydraulic oil no longer enters the cylinder, so the cylinder will not work.
How does the gas get in? There are many reasons. There may be too little oil when you adjust the sawing machine, the oil pump sucks in gas, there are too many oil connections, there may be gas in the middle, and so on !
How to solve this problem is also very simple. Loosen the screw on the top of the oil cylinder, turn on the oil pump, press the up and down buttons to let the gas out of the oil cylinder, and then tighten the screw! There are no screws at the top of the oil cylinder. In this case, one of the oil paths can be opened to make the oil pump work and discharge the gas !