Loaders can be divided into power system, mechanical system, hydraulic system and control system. As an organic whole, the performance of loader is not only related to the performance of mechanical parts of working device, but also related to the performance of hydraulic system and control system. Power system: The original power of loader is usually provided by diesel engine. The diesel engine has the characteristics of reliable operation, hard power characteristic curve, fuel economy and so on. It meets the requirements of bad working conditions and changeable load of loader.