Direct replacement water pump for Cummins 4B (3.9L) and 6B (5.9L) diesel engines. Prevents engine overheating by circulating coolant through the cooling system. Essential component for reliable engine operation in Case IH tractors and industrial equipment.
Part Number: • 3903749
Replaces OEM Part Numbers: • 4429404, 3802004, 3913432• 3802358, 3802970, 3286277• 3920311, 3389145, 3960342• 4089700, 3960309
Fits Cummins Diesel Engines: • 4B (4BT) 3.9L• 6B (6BT) 5.9L
Fits Case IH Tractor Models: • MX100, MX135, MX150, MX170• 140, 1620, 1640, 1644, 1896• 2096, 2144, 2166, 2188, 2344• 5120, 5130, 5140, 5150• 5220, 5230, 5240, 5250
Application: Designed for Cummins 4B and 6B diesel engines used in Case IH tractors, industrial equipment, and other applications. Ensures proper coolant circulation to prevent engine overheating and damage. Critical for reliable equipment performance.
Installation Note:
Replacement requires draining coolant, removing drive belt, disconnecting hoses, and removing/installing water pump. Professional installation recommended. Always use fresh coolant and follow Cummins specifications.




































