Kubota U17-3a KX41-3 KX018-4 KX019-4 RG138-61110 hidraulikus szivattyú Kubota U17-3a KX41-3 KX018-4 KX019-4 minikotró-hoz

1. Product Identification
Component: Main Hydraulic Variable Displacement Axial Piston Pump Assembly

Manufacturer Model Number: Nachi PVD-00B-15P-5G3 (PVD Series Architecture)

Kubota OEM Part Numbers: RG138-61110, RB238-61112, RG138-61114, RG138-61113, RB236-61112 (RG13861110, RB23861112, RG13861114, RG13861113, RB23661112)

Machine Compatibility:

Kubota U17-3a

Kubota KX41-3

Kubota KX018-4

Kubota KX019-4 Mini Excavator

Condition: Genuine Original New / Premium OEM Specification Equivalent

2. Technical Specifications
Pump Type: Variable Displacement Axial Piston Pump with Auxiliary Gear Section

Output Performance: Factory-calibrated flow profile, displacement limits, and operating pressure parameters matched specifically to Kubota 1.5 to 1.9-ton mini excavator circuits.

Integrated Controls: Built-in load-sensing regulators to automatically adjust fluid output based on workload demands, preventing engine lugging during multi-function operation.

Mounting & Drive: Precision mounting flange with heavy-duty input spline shaft designed for direct connection to the engine flywheel dampener drive.

3. Critical Installation Requirements
Hydraulic Pump Housing Priming (Mandatory)
Before starting the engine for the first time, manually pre-fill the pump casing with fresh, clean hydraulic fluid through its highest case drain port. Running an axial piston pump dry—even for a few seconds—will score the valve plate and piston slippers, causing immediate total pressure loss.

Air Bleeding & Initial Startup Procedure
After installation, loosen the top air bleed port on the pump housing. Crank the engine with the fuel supply disabled until bubble-free oil flows out, then re-tighten. Allow the machine to idle under no load for 10 to 15 minutes to clear remaining air in the hydraulic loop.

Fluid & System Decontamination
If replacing a pump that failed mechanically, completely drain and flush the main hydraulic reservoir, flush all feed lines, and clean the oil cooler. Always replace return and suction filter elements before starting up the machine.

Relief Pressure Check
Verify that system main relief pressures match factory specifications upon startup. Improper relief valve settings can cause sluggish hydraulic controls or lead to engine stalling under load.

4. Frequently Asked Questions (FAQ)
Q: Are part numbers RG138-61110, RB238-61112, RG138-61114, RG138-61113, and RB236-61112 interchangeable?
A: Yes. These part numbers represent standard Kubota factory engineering updates, dash revisions, and supersessions across the U17-3a, KX41-3, KX018-4, and KX019-4 model series. All cross-reference to the Nachi PVD-00B-15P platform with identical mounting dimensions and hydraulic specs.

Q: My Kubota KX018-4 stalls the engine or loses speed when performing multi-function movements. Is the main pump failing?
A: Engine stalling or loss of multi-function speed usually indicates that internal pump wear plates have scored or that the pump load-sensing regulators are no longer adjusting properly under load. Replacing the main pump assembly restores factory flow distribution and power balance.

Q: Is this pump supplied complete with the auxiliary gear pump section attached?
A: Yes. The unit comes fully assembled as a single integrated pump assembly, including the main axial piston pump section, factory-set regulator blocks, and the rear gear pump section.

5. Shipping & Logistics
Packaging: Preserved with rust-inhibiting storage oil, fitted with heavy-duty port plugs, and packed inside an export-safe protective crate or box.

Transit Time: Global express air freight via DHL/FedEx/UPS typically delivers within 3 to 7 business days directly to your workshop or job site.