PLUNGER ROD ASSEMBLY

HJ-304399

OMAX PART NUMBER: 304399

ADDITIONAL REFERENCES: 303160

Plunger Rod Assembly | HJ-304399


The HJ-304399 Plunger Rod Assembly is designed as a direct replacement for obsolete OMAX Part #303160, this precision-engineered plunger assembly restores pump performance, maintains consistent operating pressure, and helps reduce unplanned downtime caused by worn pump components.

Because the plunger assembly is a critical wear component in every OMAX pump, it is recommended replacing plungers at the scheduled maintenance intervals or whenever signs of wear, scoring, cracking, or damage are observed. Routine replacement helps protect internal pump components, extend equipment life, and ensure reliable waterjet cutting performance.

For complete pump maintenance, HJ Waterjet also offers Plunger Rod Assembly Kit P/N HJ-304885, which includes three (3) complete Plunger Rod Assemblies at a lower overall cost than purchasing three individual assemblies separately.

 

Features & Benefits

  • Part Number: HJ-304399
  • Direct replacement for obsolete P/N 303160
  • Designed specifically for OMAX and MAXIEM high-pressure pumps
  • Restores pump efficiency and pressure consistency
  • Helps minimize downtime and unexpected pump failures
  • Precision manufactured for exact fit and performance
  • Ideal for scheduled preventive maintenance and pump rebuilds
  • Compatible with Plunger Rod Assembly Kit HJ-304885

 

Applications

The HJ-304399 Plunger Rod Assembly is used in EnduroMAX high-pressure waterjet pumps installed on OMAX waterjet cutting systems. Replacing worn plungers at recommended service intervals helps maintain cutting accuracy, maximize pump reliability, and protect critical pump components from premature wear.

 

Recommended Maintenance

Inspect plunger assemblies during scheduled pump service and replace immediately if wear, scoring, cracking, or other damage is present. Following the maintenance intervals helps maximize pump life, maintain operating pressure, and reduce costly downtime.

 

Why Choose HJ Waterjet?

HJ Waterjet replacement parts are engineered to deliver premium-quality, reliable performance, precision fit, and long-lasting durability at a competitive price. Precision manufactured to exact specifications using high-quality materials and tight tolerances, our components are designed for compatibility with OEM waterjet systems and demanding industrial applications. By focusing on quality, precision, and value—not expensive branding—we help manufacturers reduce maintenance costs, minimize downtime, and maximize productivity without compromising performance or reliability. When precision matters, HJ Waterjet delivers the quality, reliability, and value professionals trust. Premium Performance Without the Premium Price

** HJ WATERJET IS IN NO WAY AFFILIATED WITH GMA, EBBCO, KENNAMETAL, KMT, FLOW, BFT, H2O, OMAX, ACCUSTREAM, HYPERTHERM OR TECHNI. PART NUMBERS ARE FOR CONVENIENCE ONLY.

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