3910582 Aftermarket Cummins 4BT/A3.9 Heat Exchanger | Sawley's Select Marine Parts

🔧 Product Description

Aftermarket replacement Engine Heat Exchanger - Replaces Part Number: 3910582

New copper-nickel heat exchanger replacing Cummins 3910582 for 4BT/4BTA 3.9L marine diesels. The approximately 4-inch × 16.25-inch exchanger retains the original compact four-cylinder installation.

⚙️ Key Features

• Direct replacement for Cummins 3910582

• Approximately 4-inch diameter × 16.25-inch shell

• Approximately 1.25-inch raw-water connection

• Copper-nickel tube bundle

• Replaceable zinc and four-inch end-cover service family

🧰 Kit / Assembly Contents

• 1 × Complete heat exchanger assembly - P/N 3910582

• 1 × sacrificial anode - replacement family 9-036

• 1 × four-inch end-cover/gasket kit - replacement family MRC4884-1A, ordered separately unless included

🔄 Supersession & Cross Reference

OEM Supersession Chain:

• 3910582 ↔ Cross-references Sendure 9445-1-7

OEM / Related Numbers:

• 9445-1-7

• 9-036

• MRC4884-1A

Aftermarket / Verified Equivalents:

• Sendure: 9445-1-7

• Mr Cool: MRC3910582CN

• Lenco: LE3910582

🚤 Compatibility

Commonly used on:

• Cummins 3.9L four-cylinder marine diesel engines

Typically suits:

• Engine / Equipment models:

• 4BT 3.9

• 4BTA 3.9

• 4BT/4BTA marine and generator applications specifying 3910582

• Output / Engine Rating: Approximately 100HP - 150HP on common marine calibrations

• Engine / System Type: Inline four-cylinder turbocharged marine diesel engine

• Year Range: 4BT/4BTA 3.9 production era

• Serial / Model Identification: Confirm engine CPL/serial and hose orientation.

🔌 Function

The heat exchanger transfers engine or generator coolant heat into the raw-water circuit while keeping the two fluids separated. This maintains the correct closed-circuit operating temperature and protects the engine from direct seawater circulation.

Common signs of failure:

• Engine or generator overheating under sustained load

• Coolant loss without an obvious external hose leak

• Saltwater and coolant cross-contamination

• Restricted raw-water discharge or uneven end-cap temperature

• Corrosion, green staining, cracked solder joints or pressure-test failure

📦 Condition

• New aftermarket replacement part

• Brand new

• Supplied in original or equivalent packaging