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177638013514-0 - Northline Parts

Water Pump MM409302 for Mitsubishi S3L S4L and K-Series Diesel Engines

SKU: NLT2I00051
$86.99 In Stock
$86.99
Sale price  $86.99 Regular price 
Ships for free in 2–4 business days.
This aftermarket engine water pump replaces Mitsubishi MM409302 and MM439303 on compatible S3L, S4L, and K-series diesel engines and equipment.
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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
  • Mitsubishi S3L, S3L2, S3L2-T, S4L, S4L2 engines
  • Mitsubishi K3A, K3B, K3C, K3D, K3E, K4C, K4D, K4E, K4E-D, K4F, K4M, K4N engines
  • Mitsubishi MT180, MT210, MT470, MT1401, MT1601, MT1801, MT2001, MT2201, MT2300
  • Case IH 234, 235, 244, 245, 254, 255, 1120, 1130
  • Cub Cadet 7000, 7192, 7193, 7194, 7195, 7200, 7205, 7232, 7233, 7234, 7235, 7260
  • Iseki TX1300, TX1410, TX1500, TX1502, TX1504, TX1510, TX1704, TX2140, TX2160, TU120, TU130, TU140, TU150, TU160, TU170, TU1400, TU1500, TU1600

Product Overview

A leaking shaft seal, loose pulley, or rough bearing can stop the pump from circulating coolant long before the engine can safely keep working. This replacement covers a large family of compact Mitsubishi diesels used in tractors, loaders, and industrial equipment.

Engine code and pump casting are better fitment checks than equipment brand alone. Compare the flange, bolt pattern, hose outlets, and pulley arrangement.

Key Features & Performance

  • Restores coolant circulation on matching Mitsubishi diesels
  • Covers S3L, S4L, and multiple K-series engines
  • Crosses MM409302 and MM439303
  • Fits several Mitsubishi, Case IH, Cub Cadet, and Iseki machines
  • Aftermarket cooling-system replacement

Replaces Part Numbers

  • MM409302
  • MM439303
  • MA-MM409302

Common Uses

  • Replacing a pump leaking coolant
  • Repairing bearing noise or pulley play
  • Restoring circulation after a confirmed pump failure
  • Rebuilding the cooling system after an overheat

Technical Specifications

  • Part Type: Engine Water Pump
  • Engine Family: Mitsubishi compact diesel
  • System: Liquid cooling
  • Replacement Type: Aftermarket
  • Quantity: One pump

Installation & Fitment

  • Drain coolant only after the engine cools
  • Compare casting, flange, and hose outlets
  • Clean the gasket surface
  • Inspect belt, thermostat, fan, radiator, and hoses
  • Refill, bleed air, and leak-test at temperature

Compatibility Notice

Northline Parts does its best to list all known compatible models, but the correct part may fit an application not shown.

Mitsubishi engine families contain pump variations. Match MM409302/MM439303, engine code, casting, and pulley interface.

Frequently Asked Questions

Q: What usually fails in a water pump? A: The shaft seal may leak or the bearing can become rough and loose.

Q: Can overheating damage the new pump? A: An unresolved belt, radiator, thermostat, head-gasket, or coolant problem can cause repeated overheating.

Q: Does it fit Case IH tractors? A: It fits the listed models when equipped with the matching Mitsubishi engine and pump.

Q: Is this OEM Mitsubishi? A: No. It is an aftermarket replacement.

Part Summary

keywords: Mitsubishi MM409302 water pump, S3L diesel coolant pump, S4L engine water pump, Case IH 235 water pump, Iseki TX1500 cooling part, MM439303 replacement

Brand names, model numbers, and reference part numbers are used for identification and compatibility purposes only. Verify the original component, dimensions, and application before purchase.

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