When using for the first time, exhaust is required. (When using, please place the oil pump on the ground as shown in the picture.) The first step is to loosen the pressure relief valve of the compressor counterclockwise. The second step is to lower the white handle of the air compressor 20-30 times (at this time, the oil cylinder of the compressor does not work). Step three, tighten the pressure relief valve clockwise and slightly. Do not tighten it too tightly, as there is a ball valve inside. Tightening it too tightly will press the ball valve into the cylinder, resulting in no pressure phenomenon. If there is still no force, you can check the oil pipe connection. The tip of the oil pipe connecting the oil cylinder needs to be inserted first, then the screw needs to be tightened, as shown in Figure 3. Otherwise, the oil in the oil pump cannot reach the oil cylinder and will not generate pressure If it still cannot be used, please do not disassemble the hydraulic components (including the pressure relief valve) by yourself. Please contact our online customer service between 9-17 pm during working hours!!! The installation diagram of the oil gauge requires two wrenches to tighten. There is a sealing ring (transparent color) at the connection between the oil gauge and the oil cylinder. Please ensure that it is installed inside and do not discard it.