2038174 Excavator Hydraulic Parts Drive Shaft for ZX120 ZX120-3 ZX130-5A ZX130-5G ZX135US-5B

Part number 2038174 is a specialized part number for the hydraulic pump drive shaft (also known as the drive shaft) of Hitachi's original excavator. This transmission shaft is a key power transmission component that connects the engine flywheel with the hydraulic main pump. According to the general information of Hitachi excavator accessories, it is mainly suitable for medium to large hydraulic excavators in the Hitachi ZX series and EX series. Common models include ZX200-3, ZX210LC-3, ZX240-3, ZX330, ZX470 and other ZX series models, as well as EX200, EX300, EX400 and other EX series models. This part is specially designed for the original factory vehicle, and its original part number is 2038174. It must be verified based on this during procurement.

The transmission shaft is the "power link" of the hydraulic system, and its core function is to efficiently and smoothly transmit the high torque rotational power of the engine to the hydraulic pump, driving the entire hydraulic system to work. As an original component, it is precision forged from high-quality alloy steel (such as 40Cr or 42CrMo) and undergoes quenching and tempering treatment and surface high-frequency quenching, possessing extremely high torsional strength, fatigue resistance, and surface hardness. The two ends of the shaft are machined with high-precision splines or flanges to ensure seamless and highly rigid connection with the engine flywheel and hydraulic pump input shaft. Strict dynamic balance correction is its key attribute, which can effectively suppress the vibration and noise generated during high-speed rotation, and protect the bearing life of the engine and hydraulic pump.

The maintenance core of this transmission shaft lies in regular inspection, maintaining alignment accuracy, and standardized fastening. Every 2000 working hours or annually, the transmission shaft spline should be shut down to check for wear, visible bending or cracks in the shaft body, and a torque wrench should be used to check whether the tightening torque of all connecting bolts has reached the specified value. Alignment adjustment: the coaxiality deviation between the engine and the hydraulic pump is the main cause of early damage to the transmission shaft. After replacing the engine floor mat, repairing the hydraulic pump, or disassembling the drive shaft, it is necessary to use a dial gauge to recalibrate the coaxiality of the two (radial and axial runout are usually required to be ≤ 0.1mm).