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Hitachi EX60-1 EX60-2 4255050 Hydraulic Main Pump Compatible with Hitachi Excavator
Welcome to Longying hydraulic supply. We specialize in providing the heavy-duty EX60-1 EX60-2 Hydraulic Main Pump (Part Number: 4255050 / 4253388), precision-manufactured as an OEM-quality aftermarket replacement compatible with Hitachi excavators and construction machinery.
Engineered to deliver maximum pressure stability and fluid flow efficiency, this hydraulic pump assembly restores original machine speed, smooth movement control, and boom lifting torque under harsh operational conditions. Ideal for fleet owners and repair workshops requiring direct drop-in replacement solutions.
Compatibility Disclaimer: This hydraulic component is an aftermarket replacement part compatible with Hitachi EX60-1 and EX60-2 excavators. All original manufacturer part numbers (e.g., 4255050, 4253388) and brand names are referenced for compatibility and identification purposes only.
Heavy-Duty Working Conditions & Scenarios
Tested under rigorous pressure loads to ensure reliable operation in challenging jobsites:
- Foundation Trenching & Digging: Provides steady oil pressure to eliminate hydraulic sluggishness during continuous bucket loading.
- Demolition & Site Preparation: Resists high pressure spikes caused by sudden hydraulic shock loads.
- Precision Lifting & Pipe Laying: Delivers smooth, non-jerky fluid flow for precise boom and arm control.
- High-Temperature Environments: Built with heat-resistant bronze valve plates and high-grade seals to prevent internal fluid bypass up to 100°C.
Troubleshooting & Repair Solutions for EX60 Hydraulic Pump Issues
Identify common failure symptoms on your machine and prevent severe system failure with our factory-calibrated pump assembly:
- Slow Machine Movement / Power Loss (全车动作发慢/掉压): Severe wear on cylinder block, pistons, and valve plate surfaces causes internal oil bypass. Solution: Complete pump assembly replacement restores original operating flow and high pressure immediately.
- High Hydraulic Oil Temperature / Overheating (热车掉速/高温发热): Excessive internal leakage weakens performance as oil heats up. Solution: Our precision-honed pump internals guarantee tight clearances and thermal efficiency during long shifts.
- Abnormal Cavitation Noise / Knocking (液压泵异响/噪音大): Caused by worn swashplate bearings, air ingress into suction lines, or damaged drive shaft splines. Solution: Pre-assembled units eliminate shaft chatter and cavitation noise.
- Hydraulic Oil Leakage from Shaft Seal (前轴封漏油): Hardened drive shaft seals allow hydraulic fluid to leak into the flywheel housing. Solution: Upgraded high-pressure FKM seals prevent shaft seal blowout.
- Jerky / Unstable Hydraulic Pressure (动作卡顿抖动): Caused by sticking control valves or scored piston shoes. Solution: Fully calibrated control valves ensure fluid, continuous cylinder action.
Popular Machinery Components Cross-Reference
Explore our trending replacement parts across major hydraulic and engine categories:
| Equipment Model (型号放前) | Part Number (零件号居中) | Product Category (品类) | Brand Compatibility (适配品牌在后) |
|---|---|---|---|
| EX60-1 / EX60-2 | 4255050 / 4253388 | Hydraulic Main Pump Assembly | Compatible with Hitachi |
| PC200-8 | 708-2L-00300 / 708-2L-00400 | Hydraulic Swing Motor Assembly | Compatible with Komatsu |
| CAT 330D / C9 Engine | 248-5613 / 386-1769 | Complete Diesel Engine Assembly | Compatible with Cater*pillar |
| CAT 320C / M318C | 191-8390 / 215-9988 | Travel Motor Final Drive Assembly | Compatible with Cater*pillar |
| ZX350-6 | 4653603 / 4638920 | Main Distributing Control Valve (分配阀) | Compatible with Hitachi |
Frequently Asked Questions (FAQ)
Q1: What problems does replacing my EX60-1 EX60-2 hydraulic main pump fix?
A: Installing a new main pump resolves slow hydraulic function, pressure loss when oil heats up (thermal fade), abnormal pump grinding noise, and shaft seal leaks, restoring original excavator working speed.
Q2: Is this hydraulic pump 4255050 a direct fit for Hitachi EX60 excavators?
A: Yes, it is manufactured according to exact OEM mounting dimensions, drive shaft splines, and hose flange ports, ensuring a plug-and-play installation compatible with Hitachi EX60-1 and EX60-2 models.
Q3: How do I know if my hydraulic issue is the main pump or the control valve?
A: If ALL machine functions (boom, arm, bucket, swing, travel) lose power simultaneously—especially when the hydraulic fluid gets warm—the issue is almost always a worn main pump rather than a single valve section.
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