4469025 4437197 hydraulpump till Hitachi ZX70 ZX75UR ZX80SB ZX85US ZX75URT ZX80LCK grävmaskin

1. Comprehensive Machine Compatibility
This pump assembly is a direct "bolt-on" replacement for several specialized Hitachi models:

Standard & Long Carriage: ZX70, ZX80LCK

Short Tail & Radius: ZX75UR, ZX85US

Specialized Series: ZX75URT, ZX80SB (Swing Boom)

Part Numbers: 4469025, 4437197 (Interchangeable revisions)

2. Technical Specifications & Features
The 70-85 series pumps are designed to maximize hydraulic efficiency in a compact frame:

Pump Type: Variable Displacement Axial Piston Pump.

Control System: Integrated with Load Sensing (LS) and Pressure Compensation (PC) regulators that adjust output based on real-time joystick demand.

Max Pressure: Rated for continuous operation at 26.5 MPa (265 bar), ensuring consistent breakout force.

Dual-Flow Logic: Designed to handle simultaneous functions (e.g., traveling while operating the boom) without stalling the engine.

3. Why Choose the Original Brand?
For midi excavators like the ZX75 and ZX85, precision is everything. Using an Original Brand pump avoids common aftermarket failures:

Perfect Metering: Original pumps allow for the "fine touch" needed when working around underground utilities. Aftermarket pumps often have "dead zones" in the joystick travel.

Matched Power Curves: These pumps are factory-tuned to the torque output of the Isuzu 4LE2 or 4TNV98 engines. This prevents the "engine lugging" common with uncalibrated units.

Heat Management: Superior metallurgy in the cylinder block and valve plate reduces internal friction, keeping oil temperatures stable during long shifts.

4. Professional Installation Protocol
To ensure the 10,000+ hour service life of your new original pump, follow these mandatory steps:

Case Priming (Mandatory): Fill the pump housing with clean hydraulic oil through the highest case drain port before starting the engine. A "dry start" will destroy the internal bronze slippers instantly.

System Decontamination: If the previous pump failed mechanically (sending metal into the oil), you must flush the hydraulic tank and clean the oil cooler.

Filtration: Always install a new suction strainer and high-pressure return filter. Use ISO VG46 anti-wear hydraulic oil.

Air Purge: After startup, run the engine at low idle for 10 minutes. Slowly cycle all cylinders to their limits to purge air from the circuit.

5. Frequently Asked Questions (FAQ)
Are the 4469025 and 4437197 parts fully interchangeable? Yes. 4469025 is typically the more recent engineering revision, offering updated seal designs and improved internal tolerances over the 4437197 version.

How can I verify if the pump is an "Original Brand"? Genuine units feature a data plate with the Hitachi or Hitachi Astemo (Nachi) logo. The casting should be clean and smooth, and the pump will arrive with high-quality protective shipping plugs in all ports.

What is the expected shipping time? We prioritize "Machine Down" situations. Global express shipping via DHL, FedEx, or UPS usually takes 3 to 7 business days to reach your location.

Does this pump include the regulators? Yes, our Original Brand New pumps are sold as complete assemblies, including the pre-calibrated LS and PC regulators.