Engine Rebuild Water Pump Assembly for Komatsu 4D82 & Yanmar 4TNE82

The Foundation of a Flawless 4D82 Engine Rebuild

When performing a complete out-of-frame overhaul on a Komatsu 4D82 or Yanmar 4TNE82 diesel engine, reusing an old, fatigued water pump is a critical mistake. A rebuilt block requires pristine thermal management to properly seat new piston rings and prevent warped cylinder heads. Engineered for professional machine shops and engine rebuilders, our heavy-duty aftermarket water pumps deliver original factory coolant flow dynamics, ensuring your 4-cylinder rebuild runs cool and reliably for its next life cycle.

Why Professional Rebuilders Trust Our Pumps

• Precision Block Matching (Avoid the 4D82 Trap): The Komatsu 4D82 engine utilizes two distinct water pump housings depending on the machine chassis (e.g., tight-clearance excavators vs. heavy-lift forklifts). We supply exact 1:1 replacements for both the compact 119810-42002 series and the high-flow 129150-42000 series. This guarantees your mechanic won't have to fight misaligned bolt holes or improper fan clearances on the engine stand.

• Severe-Duty Mechanical Sealing: Fresh engine rebuilds generate significant initial heat. Our pumps are upgraded with premium, unitized mechanical seals and high-load bearings to handle tight new belts and extreme thermal cycling without a drop of weepage.

• Maximum Cavitation Resistance: Equipped with precision-cast iron impellers that match OEM hydrodynamic specs, preventing localized block boiling and dangerous hot-spots near the exhaust valves of the 4TNE82 cylinder head.

Rebuilder's Fitment & Cross-Reference Guide

Before ordering your rebuild parts, please compare your original water pump flange design to our images and verify your part numbers below:

• Compact Housing Replacements: 119810-42002, 119810-42001 (Komatsu YM119810-42002)

• High-Flow Housing Replacements: 129150-42000, 129150-42001 (Komatsu YM129150-42000)

• Engine Block Compatibility: Komatsu 4D82, 4D82-1A / Yanmar 4TNE82, 4TN82L

• Komatsu Compact Excavators: PC40-7, PC45-1, PC50UU-2

• Komatsu Forklifts & Material Handling: FD15, FD18

• Component Type: Engine Coolant Water Pump Assembly

• Condition: 100% Brand New, Ready for Rebuild Integration