Caterpillar 3406 Marine Diesel Engine Heat Exchanger Gaskets, O-rings & Seals
Precision-Engineered Replacement Parts for CAT 3406 Marine Heat Exchangers
CAT 3406 Heat Exchanger Gaskets, O-rings & Seals
The Caterpillar 3406 Marine Diesel Engine is a proven 14.6-liter inline-six powerplant trusted in commercial vessels, tugboats, and industrial applications worldwide.
To keep these engines running efficiently, proper cooling through a clean, leak-free heat exchanger is critical.
MechPro supplies OEM-equivalent gaskets, titanium plates, o-rings, seals, bolts, spacers, collars, and complete rebuild kits for the C3406 heat exchanger assembly.
All components are manufactured to precise tolerances for corrosion resistance, thermal efficiency, and long-term durability in demanding marine environments.
If you need help identifying parts, simply send a photo or schematic of your existing heat exchanger—our team can match the correct parts quickly and ship globally.
To Schedule Parts & Service Today
Call 1 (800) 249-6709 or Use our RFQ Form

CAT 3406 heat exchanger shipped to MechPro for inspection and cleaning.

CAT 3406 heat exchanger parts and service.

CAT 3406 marine heat exchanger service.

CAT 3406 shell and tube refurbished unit.

CAT 3406 marine heat exchanger parts assembly scheme drawing.
Why Choose MechPro
- Worldwide Shipping – Fast and reliable delivery of all Cat® marine heat exchanger parts.
- Genuine & Aftermarket Options – OEM-spec compression, heat tolerance, and installation compatibility.
- Expert Support – Send us your serial number, part code, or image for instant identification help.
- Trusted Supplier – Over 15 years of heat exchanger service expertise across marine, refinery, and power generation industries.
Precision-Engineered for Reliability
Long-term durability, high fuel efficiency, simplified service, and long-life-to-overhaul — Cat® marine engines are designed for maximum productivity and minimal downtime.
A consistent maintenance schedule extends your Caterpillar engine’s lifespan and performance.
MechPro supports that mission by providing exact-fit heat exchanger components built to OEM specifications.

MechPro supplies CAT 3406 heat exchanger gaskets

Refurbished CAT 3406 heat exchanger boxed and ready for delivery.

Refurbished heat exchangers for CAT 3406 marine diesel engines.
To Schedule Parts & Service Today
Call 1 (800) 249-6709 or Use our RFQ Form
CAT 3406 Heat Exchanger Parts List (Representative Selection)
OEM part numbers for the 3406 heat-exchanger (sea-water or freshwater cooling) systems. These cover gaskets and o-rings. (Be sure to confirm serial number / configuration before ordering.)
- Oil Cooler Gasket 1264935
- Oil Cooler Gasket 4N0641
- Water Connector Gasket 1250434
- O-Ring 1090077
- O-Ring 1367227
- O-Ring 2147568
- O-Ring 3040817
- O-Ring 3678756
- O-Ring 3P0650
- O-Ring 5E8767
- O-Ring 5P7701
- O-Ring 5P7816
- O-Ring 8C0624
(Note: Part numbers are representative. Verify against your Caterpillar engine serial number or assembly drawing before ordering.)
Typical Applications
- Marine propulsion and auxiliary power units
- Tugboats, fishing vessels, workboats
- Industrial generators and compressors
- Heavy-duty trucks and equipment retrofits
Common Signs of Heat Exchanger Wear
- Coolant or seawater leakage around end caps
- Engine overheating or fluctuating temperature
- Cross-contamination between coolant and seawater circuits
- Corrosion or pitting on plates or housing
Contact MechPro to perofrm routine inspection and replacement of seals and plates that can prevent costly downtime and ensure optimal thermal performance.
Product Overview
Heat Exchanger Gaskets
Create a tight, leak-free seal between exchanger plates. Essential for efficient operation and fluid isolation.
O-Rings
Provide secondary sealing at end covers, bonnets, and water connections. These elastomeric rings prevent coolant or seawater leaks under pressure and temperature fluctuations.
Heat Exchanger Plates
Precision-engineered titanium plates maximize heat transfer efficiency, ensuring consistent cooling for 3406 diesel engines.
Heat Exchanger Seals
Durable elastomeric seals prevent leaks at joints and maintain proper pressure within the system.
Together, these components sustain optimal engine cooling performance, prevent overheating, and extend engine life.
Caterpillar 3406 Marine Engine Specs
| Specification | Detail |
|---|---|
| Engine Type | Inline 6-Cylinder Diesel |
| Displacement | 14.6 L (893 cu in) |
| Bore × Stroke | 5.4 in × 6.5 in (137 × 165 mm) |
| Compression Ratio | 14.5:1 – 15.8:1 (depends on variant) |
| Aspiration | Turbocharged / Aftercooled |
| Horsepower Range | 310 – 485 HP (231 – 362 kW) |
| Max Torque | Up to 1,850 lb-ft (2,500 N·m) |
| Rated Speed | 1,800 – 2,100 RPM |
| Fuel Type | Diesel |
| Fuel System | Mechanical or Electronic Unit Injection (variant dependent) |
| Cooling System | Freshwater to Raw-Water Heat Exchanger |
| Oil Capacity | Approx. 10 gal (40 qts) |
| Rotation (from flywheel end) | Counterclockwise |
Request a Quote
Whether you need a single gasket or a full heat exchanger rebuild kit, MechPro can help.
📞 Call: 1 800 249-6709
📧 Email: [email protected]
Or simply use our Request for Quote form to send us your engine model and photos of the exchanger — we’ll handle the rest.
CAT 3406 FAQs
Q: What are the typical applications for the CAT 3406 Marine Engine?
A: The CAT 3406 is widely used in workboats, fishing vessels, and marine generators due to its reliability and serviceability. It also powers industrial and on-highway applications.
Q: How often should the heat exchanger plates and gaskets be replaced?
A: Inspection is recommended annually, or every 2,000–3,000 operating hours. Have plates or seals replaced if you observe leaks, corrosion, or reduced cooling efficiency.
Q: Are MechPro CAT 3406 parts compatible with OEM Caterpillar components?
A: Yes — the plates and gasket kits we supply are precision-matched to OEM specifications for fit, material, and thermal performance, ensuring seamless installation and reliability.
Q: What kind of heat exchanger is typically used for a CAT Marine diesel 3406 engine?
A: The heat exchanger typically used for a CAT Marine diesel 3406 engine is a tube and shell heat exchanger.
This design is common for marine engine applications, including the 3406, where it is used to transfer heat from the freshwater engine coolant to the raw (sea) water, keeping the two fluids separate to prevent corrosion of the engine’s internal components. The units are often made with corrosion-resistant materials like bronze and copper-nickel (CuNi) for durability in the harsh marine environment.
While plate heat exchangers are also used in some marine applications, the shell and tube type is generally the standard and most popular factory-fitted design for the main engine cooling system on the Cat 3406.
Disclaimer
All manufacturer names, part numbers, and product descriptions are provided for reference and identification purposes only. Caterpillar®, CAT®, and associated model names and numbers are registered trademarks of Caterpillar Inc.
MechPro is not an authorized dealer for Caterpillar Inc. and is not affiliated with the company. Our inventory is constantly changing and may include both genuine OEM parts and high-quality aftermarket replacements. Unless explicitly stated, we do not guarantee that a listed item is manufactured by the original equipment manufacturer.
Product images, diagrams, and specifications are for reference only and may not exactly match the item shipped. Customers should use original part numbers to verify compatibility and determine the most suitable replacement for their needs.
