4933306 / 3977272 / 4933309 Aftermarket Cummins 5.9L B-Series Aftercooler Bundle | Sawley's Select Marine Parts

🔧 Product Description

Aftermarket replacement Aftercooler Tube Bundle/Core - Replaces Part Number: 4933306

New copper-nickel aftercooler bundle replacing Cummins 4933306, 3977272 and 4933309. It is the removable heat-transfer core used inside the 5.9L B-series marine aftercooler housing.

⚙️ Key Features

• Bundle/core-only replacement

• Cross-references Cummins 4933306, 3977272 and 4933309

• Copper-nickel seawater tube construction

• Designed for 6BTA 330/370 Diamond and QSB 5.9 aftercoolers

• Allows overhaul of a serviceable original housing

🧰 Kit / Assembly Contents

• 1 × Aftercooler tube bundle/core - replacement P/N 4933306 / 4933309

• Housing, end covers, O-rings, stabiliser strips and mounting hardware are not included unless stated

• Use Service Kit A P/N 4025341-13A for the required seals and core stabilisers where applicable

🔄 Supersession & Cross Reference

OEM Supersession Chain:

• 4933309 → Later service reference associated with 4933306

• 4933306 → Cross-references 3977272

• 3977267 / 4019971 (related B-series aftercooler-core references on specified housings)

OEM / Related Numbers:

• 3977272

• 4933309

• 3977267

• 4019971

• 4025341-13A

Aftermarket / Verified Equivalents:

• SMX/Seaboard Marine: AC-BCCORE-KIT

• Mr Cool: MRC4933309 aftercooler bundle

• Seakamp copper-nickel B-series aftercooler core

🚤 Compatibility

Commonly used on:

• Cummins 5.9L B-series marine aftercoolers

Typically suits:

• Engine / Equipment models:

• 6BTA 5.9 330 Diamond

• 6BTA 5.9 370 Diamond

• QSB 5.9 applications using the serviceable B-series aftercooler housing

• Output / Engine Rating: Approximately 330HP - 380HP

• Engine / System Type: Inline six-cylinder turbocharged and seawater-aftercooled marine diesel engine

• Year Range: 6BTA Diamond/QSB 5.9 production; housing- and serial-dependent

• Serial / Model Identification: Pressure-test the housing and replacement bundle separately; order the seal/stabiliser kit at the same time.

🔌 Function

The tube bundle is the heat-transfer core inside the aftercooler housing. Raw water passes through the bundle while compressed intake air passes around it, reducing charge-air temperature before combustion.

Common signs of failure:

• Loss of power or elevated exhaust-gas temperature

• Restricted seawater flow through the aftercooler

• Saltwater staining or corrosion inside the housing

• Charge-air temperature remaining excessive under load

• Bundle leakage or failed pressure test

📦 Condition

• New aftermarket replacement part

• Brand new

• Supplied in original or equivalent packaging