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SKU:
NLT2T02642
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Water Pump 121450-42010 for Yanmar 3T80U-NB / UNA / SB / SA Engines
$83.69
In Stock
$83.69
Sale price
$83.69
Regular price
This water pump serves Yanmar 3T80U engine variants including 3T80U-NB, 3T80UNA, 3T80U-SB and 3T80U-SA.
Estimated delivery between
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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.
Compatible equipment / model
| Brand / Family | Compatible Applications |
|---|---|
| Yanmar | 3T80U-NB, 3T80UNA, 3T80U-SB, 3T80U-SA |
Product Overview
It circulates coolant through the engine and radiator circuit so the 3T80U can shed heat under sustained work. Replacing a leaking or loose pump before bearing failure helps protect the head, gasket and cooling system from an overheat event.
Common matching listings for this pump family include a mounting gasket; confirm package contents shown for this listing.
Key Features & Performance
- Maintains coolant circulation: Keeps coolant moving through the engine and radiator so heat can be rejected under working load.
- Serviceable wear point: Seal leakage, shaft play, bearing noise or pulley wobble are common reasons to replace an aging pump.
- Fitment by engine and pump geometry: Casting, hub height, pulley arrangement and reference number should match the original pump.
- Product-specific note: Common matching listings for this pump family include a mounting gasket; confirm package contents shown for this listing.
Technical Specifications
- Drive: Belt-driven engine water pump
- Engine family: Yanmar 3T80U
Replaces / Reference Part Numbers
121450-42010, 129350-42010, 121023-42100
Common Replacement Reasons
- Coolant leakage from the pump/weep area
- Bearing noise, shaft play or pulley wobble
- Overheating with belt, radiator, thermostat and coolant level otherwise checked
Frequently Asked Questions
How do I confirm this is the correct part?
Match the original casting, hub/pulley arrangement and one of the listed reference numbers before ordering.
Is this an OEM part?
Unless the listing is explicitly identified as genuine/OEM in the product data, treat it as a replacement component. Use the verified reference numbers, equipment application and physical configuration above to match your original part.
What should I check before installation?
Inspect the fan/pulley for wobble and check the weep area for coolant tracks when diagnosing an old pump.
Fitment note: Equipment manufacturers may use different components within the same model family based on engine, serial number or production date. Confirm the original part number and machine/engine details before ordering.