4198956 Original Excavator Hydraulic Pump Pin for ZX200-5A

The original hydraulic pump pin part number 4198956 is a hydraulic pump positioning pin shaft provided by Hitachi Construction Machinery for the ZX200-5A 20 ton hydraulic excavator (with a total working weight of approximately 20.2 tons). This pin is mainly used for the installation and positioning of hydraulic pump assemblies (such as K5V200 or HPV102/118 series variable axial piston pumps) and engine flywheel housings or transmissions, ensuring precise alignment between the pump body and drive components, and preventing abnormal wear, vibration, or oil leakage caused by misalignment. Its universal model is usually directly labeled as 4198956 and is also applicable to other Hitachi ZX series models such as ZX890-5A. It belongs to the standard cylindrical positioning pin and can be interchanged with M5 × 180 pin shafts of the same size specifications. However, to ensure positioning accuracy and reliability, it is strongly recommended to use genuine original parts from the factory.

This product is an original hydraulic pump positioning pin shaft made of high-strength alloy steel (such as 45 # steel or 40Cr), which has undergone quenching and tempering heat treatment and surface galvanizing anti rust treatment. One end has a guide chamfer for easy installation, while the other end may have a snap groove or threaded hole for axial fixation. Pin shaft hardness ≥ 40 HRC, shear strength ≥ 500 MPa, working temperature range -30 ℃ to+120 ℃, suitable for harsh working conditions of excavator hydraulic pumps with high vibration and high load. Its core function is to ensure the coaxiality (error ≤ 0.05 mm) between the hydraulic pump and the driving components, thereby ensuring stable hydraulic system pressure (maximum flow rate of the main pump 2 × 212+30.2 L/min, working pressure 34.3 MPa) and transmission efficiency.

Pre installation inspection: Confirm the clearance between the pin shaft and the pin hole (usually H7/g6, clearance 0.01-0.03mm); Check the surface of the pin shaft for rust, burrs, and cracks. Installation points: Use specialized installation tools or copper rods to gently tap in, and violent hammering is strictly prohibited; Ensure that the pin is fully in place, and if necessary, apply medium strength thread fastener to the threaded end to prevent loosening. Operation monitoring: Check the torque of the hydraulic pump installation bolts (usually 120-150 N · m according to the original factory specifications) and the pin shaft for looseness, wear, and deformation every 500 working hours. Fault diagnosis: If there is abnormal noise or increased vibration in the hydraulic pump, it may be due to poor alignment caused by worn pin shafts; If the pin shaft breaks, it is often due to overload impact or material defects.