4723333 Original Excavator Gear Pump for ZX180W-7

The Hitachi excavator gear pump (part number: 4723333) is a critical component in hydraulic systems that provides a stable oil source for auxiliary circuits or pilot systems. According to industry accessory information, this gear pump, as a universal auxiliary pump, is widely compatible with multiple series of Hitachi excavators, especially the ZX series models with small and medium tonnage, such as ZX120, ZX200, ZX210, ZX240, ZX330, etc. At the same time, this part number is often circulated in the accessory market as a universal part number, compatible with some old EX series models.
 

This gear pump belongs to the external meshing quantitative pump and is a power component in the hydraulic system. Its core function is to convert the mechanical energy of the engine into hydraulic energy, providing stable low-pressure oil flow for the excavator's pilot control system, swing brake release, fan drive, or other auxiliary functions. As an original or high-quality substitute, it is usually made of high-strength alloy steel gears and cast iron pump bodies precision machined, with characteristics such as compact structure, reliable operation, and strong anti pollution ability. The key performance parameters typically include: rated displacement (such as 10-30 cc/rev), rated pressure (usually 2.5-4 MPa), maximum speed, and inlet and outlet thread specifications.

Every 1000 hours, the outlet flow rate and pressure of the pump can be considered for testing. If there is a significant decrease, the internal wear condition needs to be checked. When disassembling and repairing, all parts need to be cleaned, and the gear tooth surface, pump body inner wall, and side plate should be checked for scratches or excessive wear. If necessary, the gears and shaft sleeves should be replaced in pairs. During installation, ensure that the coupling is well aligned and tighten the installation bolts to the standard torque. Maintaining clean oil and good system sealing is the key to extending the service life of gear pumps.