K4V45 Kawasaki Replacement Excavator Hydraulic Main Piston Pump

The K4V45C264R-R2652C high-pressure swashplate axial piston pump manufactured by LIC Hydraulic belongs to the rugged K4V/K3V and NVK45 product families. It is engineered as the primary hydraulic power source for modern mini-to-midi excavators. In terms of mounting pilot dimensions, input spline shaft specifications, SAE port flanges, and regulator control curves, this pump provides 100% drop-in interchangeability with the original Kawasaki and NVK45 equipment.

To withstand the severe mechanical stresses and pressure spikes encountered during intensive digging and simultaneous multi-actuator motion, LIC utilizes premium metallurgic compounds and specialized heat treatment for both the complete pump assemblies and replacement rotary groups (including cylinders, pistons, and valve plates). Every K4V45 unit undergoes 100% full-load simulated excavator condition testing prior to shipment. This ensures reliable volumetric performance under continuous 34.3 MPa workloads, delivering a robust and economical procurement choice for the global B2B heavy equipment aftermarket.

Technical Specifications

Accurate engineering profile based on catalog standards for configuration K4V45C264R-R2652C:

• Product Series: K4V / K3V / NVK High-Pressure Swashplate Axial Piston Pump

• Complete Model Code: K4V45C264R-R2652C

• Nominal Displacement: 45.0 cm³/rev

• Rated Operating Pressure: 34.3 MPa (343 bar)

• Maximum Peak Pressure: 39.2 MPa (392 bar)

• Maximum Continuous Speed: 2600 rpm

• Self-Priming Speed Limit: 2200 rpm (Standard open circuit)

• Control Mechanism: Total Horsepower Control (Constant Power) + Pressure Limiter Control with hydraulic pilot servo actuator

• Input Shaft Format: SAE Standard Spline Shaft

• Rotation Direction: R (Right Hand / Clockwise from shaft end view)

• Component Availability: Complete pump assembly and internal cartridge parts (cylinder block, piston shoes, valve plate, set plate, swashplate assembly)

• Net Unit Weight: Approx. 32.0 kg (70.5 lbs)

Key Technical Advantages

• High-Dynamic Variable Displacement Regulator: LIC optimizes the feedback spring sets and internal pilot spool clearances within the variable control regulator. The micro-ground spool valve pairs ensure the pump’s output curve matches the engine’s power profile. When excavation resistance spikes, the regulator alters the swashplate angle within milliseconds, preventing engine stall.

• Bimetallic Sintered Valve Plate with Anti-Vibration Grooves: The core valve plate consists of a high-strength steel substrate bonded with a friction-reducing copper alloy layer. Precision-engineered fluid decompression slots and fluid dumping holes are machined onto the face. This architecture significantly dampens transient pressure ripples, reducing operational noise by 3-4 dB(A).

• Nitrided Alloy Pistons & High-Density Cylinder Block: The nine piston shoes are fabricated from high-grade chromium alloy steel subjected to multi-stage nitriding and mirror polishing, matched with a high-tensile ductile iron cylinder block. Micro-clearances are calibrated to preserve a stable hydrodynamic oil film at 34.3 MPa, preventing shoe-slipper delamination or cylinder face scoring.

• Heavy-Duty Shock-Absorbing Tapered Roller Bearings: To counter the external radial and axial vibrations typical of excavator powertrains, LIC replaces standard bearings with large-capacity tapered roller bearings. This enhancement secures shaft alignment, absorbs drivetrain vibration, and extends the operational lifespan of the main pump.

Application Areas

The K4V45C264R high-pressure pump and its internal replacement components are utilized extensively across the global B2B construction machinery repair sector:

• Crawler Excavators: Primary hydraulic main pump replacement for 6-ton to 9-ton midi-excavators (e.g., specific Kobelco, Hyundai, and Sany models utilizing Kawasaki or NVK systems).

• Rotary Drilling & Piling Rigs: Delivering high-pressure pilot or auxiliary rotational power to secondary winch and swing systems.

• Wheeled Excavators & Skid Steer Loaders: Serving as the heavy-duty fluid power core for high-frequency open-loop hydraulic circuits.

Expert Maintenance Tips

• Mandatory Pre-Priming Before Startup: When installing a new pump or executing a major overhaul with replacement parts (such as a new cylinder block and pistons), always pre-fill the pump housing with clean hydraulic oil through the topmost case drain port before cranking. Jog the engine several times and idle under zero load for 10 minutes to purge air from the internal chambers and regulators to avoid dry friction.

• Maintain Reservoir Micro-Positive Pressure: Excavator hydraulic loops cycle rapidly. To eliminate the risk of inlet cavitation and destructive pitting during high-RPM transitions, verify that the hydraulic reservoir’s air breather/pressurizer valve is operating properly (maintaining 0.2 to 0.5 bar of positive tank pressure). Inspect and clean suction strainers routinely.

• Enforce Tight Fluid Cleanliness Standards: High-pressure piston pumps operate with precise tolerances and are highly vulnerable to particulate abrasion. Keep system oil cleanliness calibrated to ISO 4406 18/15/12 (NAS Class 7) or cleaner. Micro-particles entering the cylinder-to-plate interface act as abrasives, causing rapid pressure drops and internal leakage.