Water Pump 129004-42001 for Yanmar 4TNV84 4TNV88 Engines / Komatsu PC50
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Compatible Models
We do our best to list all compatible models. Although this may be the part you need, your exact model may not appear below.
| Engine | Yanmar 4TNV84, 4TNV84-GGE, 4TNV88 |
|---|---|
| Equipment | Certain Komatsu PC50 excavator applications using the matching Yanmar engine/pump configuration |
Product Overview
A worn water pump can show up as coolant seepage, bearing noise, overheating, or inconsistent coolant circulation. This pump is intended to restore normal coolant flow through compatible Yanmar 4TNV84/4TNV88 cooling systems so the engine can hold a stable operating temperature under load.
The 129004-42001 pump family is also commonly cross-referenced with YM129004-42001 and related Yanmar pump numbers including 129508-42001 and 129100-42002/42004. Because these engines appear in more than one equipment installation, compare the housing, pulley/fan mounting arrangement and hose connections with the pump being removed.
Key Features & Performance
- Restores coolant circulation through the engine and radiator circuit
- Useful replacement when the original pump leaks, develops shaft play or becomes noisy
- Direct application for Yanmar 4TNV84 and 4TNV88 engine families
- Multiple Yanmar cross-reference numbers make part-number matching easier
Specifications & Reference Numbers
- Primary reference: 129004-42001 / YM129004-42001
- Common cross references: 129508-42001, 129100-42002, 129100-42004
- Part type: Engine water pump
Before You Order
Verify the stamped/cast part number and compare the pump housing, hub and hose-port layout. Komatsu model alone is not enough because engine and serial-number configurations can vary.
Frequently Asked Questions
What should I use as the final fitment check? Use the listed part/reference numbers, your exact engine or machine model, and the physical configuration of the part being replaced. Serial-number and production changes can matter.
What are common reasons to replace this part? A worn water pump can show up as coolant seepage, bearing noise, overheating, or inconsistent coolant circulation. This pump is intended to restore normal coolant flow through compatible Yanmar 4TNV84/4TNV88 cooling systems so the engine can hold a stable operating temperature under load.