4391321 Boom Cylinder Seal Kit for Hitachi EX750-5 EX800H-5 Excavator
Premium aftermarket 4391321 boom cylinder seal kit engineered specifically for large-class Hitachi EX750-5 and EX800H-5 mining excavators. High-quality heavy-duty seals for reliable leak prevention and robust lifting performance.
Brand: WINSCHEN
Country of Origin: CHINA
Minimum order quantity: 1 SET
Delivery time: 1-3 Days
SKU: HIT-4391321
Premium 4391321 Boom Cylinder Seal Kit for Hitachi Mining Excavators
Eliminate hydraulic fluid leaks and restore the massive lifting power of your heavy-duty excavator with the WINSCHEN premium 4391321 Boom Cylinder Seal Kit. Engineered specifically to withstand the extreme operational pressures, massive heavy-duty payloads, and highly abrasive environments of large-scale quarrying and mining, this high-quality aftermarket repair kit ensures your Hitachi equipment operates safely and efficiently with zero pressure loss.
Key Features and Selling Points
- Manufactured to strict OEM dimensions, ensuring a precise and seamless fit for the boom hydraulic cylinders used in large-class Hitachi EX750-5 and EX800H-5 excavators.
- Constructed from advanced elastomeric, polyurethane, and heavy-duty PTFE materials to provide exceptional resistance to high hydraulic pressure spikes, continuous rod friction, and extreme thermal variations common in mining applications.
- Effectively eliminates internal fluid bypass and external leakage, preventing boom drift and maintaining highly responsive, consistent lifting force for massive bucket loads.
- This comprehensive seal kit includes all essential precision components—such as heavy-duty rod seals, dust wipers, buffer rings, and O-rings—required for a complete and reliable boom cylinder overhaul.
- A cost-effective, highly reliable aftermarket alternative that meets or exceeds original equipment standards, significantly minimizing your machine’s routine maintenance downtime and maximizing quarry production.
Compatible Equipment Models
Based on official catalog and parts cross-reference data, the 4391321 seal kit services the boom cylinders of the following Hitachi equipment:
- Large Crawler Excavators: EX750-5, EX800H-5
- Application: Boom Cylinder Hydraulic Service / Rebuild
Specifications
| Part Number | 4391321 |
| Part Type | Boom Cylinder Seal Kit |
| Application | Hydraulic System Maintenance |
| Brand | WINSCHEN (Premium Aftermarket) |
| SKU | HIT-4391321 |
| MOQ | 1 Set |
| Delivery Time | 1-3 Days |
To guarantee 100% fitment, please verify your machine’s model, serial number, and original cylinder configuration with our dedicated support team prior to purchasing. We proudly offer fast and reliable global shipping to keep your heavy-duty projects on schedule.
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