JPR-C1025 Aftermarket Cummins 4BT/A 3.9M & 6BT/A 5.9M Seawater Pump Sherwood M7, M71, M71-01 | Sawley's Select Marine Parts

🔧 Product Description

Aftermarket replacement 4B/6B 1-1/4-Inch Seawater Pump - Part Number: JPR-C1025

New aftermarket engine-cooling seawater pump for Cummins 4B3.9M, 4BT3.9M and 4BTA3.9M, Cummins 6B5.9M and 6BT5.9M. It replaces the listed OEM pump family and is supplied as a complete assembled pump. Not interchangeable with Cummins 3349340/Sherwood G1503. For 1-1/2-inch ports use DJ C0830.

⚙️ Key Features

• Direct aftermarket replacement for JPR-C1025

• Heavy-duty marine-grade bronze or corrosion-resistant pump construction

• Gear-driven direct replacement pump

• Port configuration: 1-1/4-inch / 32mm inlet and outlet

• Serviceable flexible-impeller design with replaceable cover, cam, seal, shaft and bearings

🧰 Kit / Assembly Contents

• 1 × Complete seawater pump assembly - Part Number: JPR-C1025

• 1 × Installed impeller - JMP 7300-01K

• 1 × Installed shaft, bearing, cam and mechanical-seal assembly

• 1 × Installed end cover with gasket or O-ring sealing system

• Mounting / installation: Mounting gasket supplied separately unless stated

🔄 Supersession & Cross Reference

OEM Supersession Chain:

• JPR-C1025 → Replaces / cross-references 3907458

• JPR-C1025 → Replaces / cross-references 3912019

OEM / Related Numbers:

• 3907458

• 3912019

Aftermarket / Verified Equivalents:

• Sherwood: M7

• Sherwood: M71

• Sherwood: M71-01

• JMP Marine: JPR-C1025

Service Parts / Kits:

• Major service kit: JMP JSK0047

🚤 Compatibility

Commonly used on:

• JMP Marine / Cummins marine engine-cooling systems

Typically suits:

• Engine models:

• Cummins 4B3.9M, 4BT3.9M and 4BTA3.9M

• Cummins 6B5.9M and 6BT5.9M

• HP / Output Range: Engine- or generator-rating dependent

• Engine Type: Marine diesel, petrol or generator engine as listed above

• Year Range: Engine-model, arrangement and serial-number dependent

• Port / Drive Identification: 1-1/4-inch / 32mm inlet and outlet; Gear-driven direct replacement pump. Confirm rotation, shaft/gear style, flange, port direction and mounting seal before ordering.

🔌 Function

The engine-driven flexible-impeller seawater pump draws raw water through the vessel's intake and strainer, then circulates it through the heat exchanger, charge-air cooler, exhaust mixer and other seawater-cooled components. Adequate flow is essential for controlling engine and exhaust temperatures.

Common signs of failure:

• Engine or exhaust temperature rises above normal

• Weak or absent seawater discharge at the exhaust outlet

• Impeller blades are cracked, missing, swollen or permanently set

• Water leaks from the pump cover, shaft seal, drain hole or mounting flange

• Bearing noise, shaft play or a seized pump drive

📦 Condition

• New aftermarket replacement seawater pump

• Brand new

• Supplied in original or equivalent packaging