Kawasaki Hydraulikpumpe für Kobelco SK120-5.5 Midibagger

SK120‑5.5 Hydraulic Pump for Excavator spare parts Main Hydraulic pump OEM

Product Overview

This OEM‑grade variable displacement axial piston main pump serves as the core hydraulic power source for Kobelco SK120‑5.5 medium crawler excavator. It converts engine mechanical energy into high‑pressure adjustable hydraulic flow to drive boom, arm, bucket, travel assembly and swing motor to complete all excavation actions. This machine is widely applied in urban earthwork, foundation excavation, road renovation and material stacking projects. Under long‑term variable‑load construction and harsh site conditions, internal core components including cylinder block, piston assembly, valve plate and slipper will gradually suffer fatigue wear. Typical failure manifestations cover insufficient digging force, slow cylinder response, continuous hydraulic oil overheating, harsh knocking noise from pump housing and serious internal leakage. Manufactured strictly according to original OEM drawing standards, this main pump supports direct drop‑in replacement for worn original unit, restores the machine’s original working capacity, and effectively avoids secondary damage to multi‑way valve, hydraulic motor and other high‑cost hydraulic components.

Core Advantages

1. High‑durability friction pair adapts to medium excavator complex working cycles
Key friction contact components adopt high‑strength alloy steel and receive professional surface quenching treatment. Optimized surface hardness improves anti‑abrasion performance against tiny metal debris and impurity particles mixed in hydraulic oil. It can output stable pressure and flow under frequent compound actions, continuous heavy‑load excavation and intermittent idling conditions in urban construction sites.

2. Pre‑calibrated power regulator matches original machine power matching curve
The built‑in pressure‑flow regulator is debugged according to OEM original parameters. It reasonably distributes engine power between travel system and working devices, lowers overflow energy loss and suppresses excessive system heat accumulation. Operators can obtain smooth and coordinated movements during digging, lifting and slewing without obvious power lag or action stuttering.

3. Full dimensional interchangeability shortens on‑site repair downtime
Mounting hole layout, input spline specification, inlet‑outlet oil port dimension and regulator installation position are fully consistent with original pump. Maintenance technicians can complete pump replacement directly on‑equipment without additional machining, cutting or pipeline refitting. It greatly reduces machine stand‑still loss for repair workshops, project fleets and global spare‑parts distributors.

4. Precisely controlled assembly clearance minimizes internal bypass leakage
Each mating component passes fine grinding processing. Assembly gaps are strictly controlled within OEM tolerance scope. It obviously improves internal leakage caused by component wear, resolves common faults such as weak digging power and slow implement movement, and prolongs maintenance cycle of the whole hydraulic system.

5. Reliable OEM‑level solution for medium‑size excavator maintenance supply chain
With stable field durability and reasonable procurement cost, this hydraulic pump fits well for Kobelco equipment owners, local repair garages and overseas spare‑part wholesalers. It provides dependable support for overhaul and maintenance projects of SK120‑5.5 excavator units.

Manufacturing & Quality Control

Our production base specializes in manufacturing main hydraulic pumps for medium construction excavators. Complete quality control workflow includes incoming raw‑material inspection, key component dimension verification, heat‑treatment hardness testing, sub‑assembly screening and finished‑product hydraulic bench test. Every finished pump must pass pressure‑holding test, flow detection and noise check before shipment to eliminate defective units. After anti‑rust preservation treatment, pumps are wrapped with shock‑absorbing cushion materials and packed in export‑qualified wooden cases, preventing collision deformation and moisture corrosion during cross‑border sea‑land transportation. Sample testing order, small‑batch trial purchase and large‑volume bulk order are all acceptable for worldwide clients.

Frequently Asked Questions
Q1: What abnormal phenomena mean main pump inspection or replacement?
A: If your SK120‑5.5 excavator shows obvious insufficient digging capacity, slow boom and bucket response, persistent high hydraulic oil temperature, harsh knocking noise from pump compartment, and these problems cannot be eliminated by adjusting regulator or replacing filter elements, you need to inspect or replace the main hydraulic pump.

Q2: Can this OEM pump be directly installed on SK120‑5.5 excavator?
A: It is engineered as OEM‑grade direct replacement for SK120‑5.5 main pump assembly. Please double‑check your old pump part number and machine configuration before placing order. Different production batches may be equipped with different pump assemblies even for the same excavator model.

Q3: What critical steps should be completed after finishing hydraulic pump replacement?
A: Thoroughly clean hydraulic oil tank, replace all matching hydraulic filter elements and fill with hydraulic oil that meets Kobelco specification. Fully bleed trapped air inside hydraulic pipelines after installation. Conduct low‑speed no‑load running‑in firstly, then carry out gradual load test; do not execute heavy‑duty full‑load operation immediately after pump installation.

Q4: Description for product warranty scope
A: Our warranty covers defects caused by raw‑material flaw and manufacturing error. Damage induced by hydraulic oil contamination, improper oil viscosity, foreign matter entering pump interior, long‑time over‑load operation and incorrect installation procedure is excluded from warranty coverage. Please perform overhaul work complying with Kobelco official service manual.