3393663CN Aftermarket Cummins 6BTA Oil Cooler 3 x 6 in, 1.5 in | Sawley's Select Marine Parts

🔧 Product Description

Aftermarket replacement Transmission Gear-Oil Cooler - Replaces Part Number: 3393663CN

New copper-nickel transmission/gear-oil cooler replacing Cummins 3393663. Despite being catalogued in some listings as an engine-oil cooler, this unit is used in the marine gearbox cooling circuit.

⚙️ Key Features

• Direct replacement for Cummins 3393663

• Approximately 3-inch diameter × 6-inch bundle

• Approximately 1.5-inch seawater connection on the listed configuration

• Copper-nickel tube bundle

• Used with selected 6BTA and QSL9 marine gearbox installations

🧰 Kit / Assembly Contents

• 1 × Complete transmission/gear-oil cooler - P/N 3393663CN

• 1 × integrated copper-nickel tube bundle

• Sacrificial-zinc positions and drain fittings according to manufacturer configuration

• Oil-line fittings and mounting brackets are renewed separately

🔄 Supersession & Cross Reference

OEM Supersession Chain:

• 3393663CN → Copper-nickel replacement for Cummins 3393663

• Sendure 12717-1-7 (related replacement)

OEM / Related Numbers:

• 3393663

• 12717-1-7

Aftermarket / Verified Equivalents:

• Sendure: 12717-1-7

• Mr Cool: MRC3393663CN

• Lenco: LE3393663

🚤 Compatibility

Commonly used on:

• Cummins marine propulsion packages with separate ZF or equivalent marine gearbox

Typically suits:

• Engine / Equipment models:

• 6BTA 5.9 315, 330 and 370 Diamond Series installations

• Selected QSL9 marine installations specifying 3393663

• Output / Engine Rating: Approximately 315HP - 405HP on common applications

• Engine / System Type: Inline six-cylinder turbocharged marine diesel with separate transmission

• Year Range: Engine- and gearbox-serial dependent

• Serial / Model Identification: Confirm seawater-hose diameter because replacement variants may use 1.5-inch or 1.75-inch connections.

🔌 Function

The cooler transfers heat from transmission or reduction-gear oil into the raw-water circuit. Correct oil temperature protects clutches, bearings, seals and hydraulic control components.

Common signs of failure:

• High transmission or reduction-gear oil temperature

• Burnt, darkened or aerated gear oil

• Delayed engagement, slipping or abnormal gear noise when hot

• Water-contaminated or milky transmission oil

• External oil leakage, corrosion or failed pressure test

📦 Condition

• New aftermarket replacement part

• Brand new

• Supplied in original or equivalent packaging