This arm seal kit, part number YNF16739, is precisely manufactured for Hyundai R145-9 excavators. It corresponds to the OEM number 31Y1-31150 and is specifically designed for the arm hydraulic cylinder, also known as the mid-boom cylinder. This kit provides all the critical sealing components necessary for a complete cylinder rebuild, ensuring optimal performance and extended equipment life.

Engineered to meet or exceed OEM performance standards, this seal kit delivers exceptional resistance to high pressure, fluid abrasion, and temperature variations. It helps restore hydraulic system integrity and minimizes costly downtime due to fluid leakage or seal failure.

Machine Compatibility

• Model: Hyundai R145-9

• Application: Arm (mid-boom) hydraulic cylinder

• OEM Reference: 31Y1-31150

Kit Components
The YNF16739 arm seal kit includes:

• Rod seal

• Piston seal

• Dust seal/wiper

• Buffer seal

• Wear ring

• O-rings and backup rings

Each component is made from high-performance materials such as PU (polyurethane), NBR (nitrile rubber), and PTFE (Teflon), ensuring excellent oil resistance, temperature stability, and durability.

Advantages

• Precise OEM Fit: Direct replacement for 31Y1-31150, requires no modification.

• Extended Seal Life: Built to operate in harsh environments and under high stress.

• Leak-Proof Design: Seals hydraulic oil effectively, prevents system pressure loss.

• Easy Maintenance: Simplifies the repair process, reduces machine downtime.

• All-In-One Kit: Includes every necessary component for a full cylinder rebuild.

Applications
This kit is ideal for maintenance shops, heavy equipment operators, and field repair services performing cylinder overhauls on Hyundai R145-9 excavators.

Technical Specifications:

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