Caterpillar 3406 Marine Engine Parts & Spare Parts
Alfa Marine Spare Parts supplies Caterpillar 3406 marine engine parts and spare parts for commercial vessels, fishing vessels, workboats, tugboats, marine propulsion systems, auxiliary engines and generator applications.
We source genuine, OEM, replacement and applicable Reman Caterpillar 3406 components, subject to availability, for scheduled maintenance, corrective repairs, top-end overhaul and complete engine rebuild requirements.
Our sourcing capabilities cover fuel injectors, fuel nozzles, fuel injection pumps, cylinder heads, pistons, cylinder liners, piston rings, connecting rods, bearings, crankshaft components, camshaft components, turbochargers, seawater pumps, jacket-water pumps, oil pumps, oil coolers, aftercooler components, filters, starters, alternators, gaskets, seals and overhaul parts.
The Caterpillar 3406 belongs to the wider Caterpillar 3400 Series Marine Engine Parts family.
Important versions include:
- Caterpillar 3406
- Caterpillar 3406B
- Caterpillar 3406C
These designations should not automatically be treated as identical when selecting replacement components.
For other Caterpillar engines, browse our Caterpillar Marine Engine Parts & Rebuild Kits or Caterpillar Engine Parts Catalogue.
For correct identification, provide the complete engine designation, engine serial number, serial-number prefix, arrangement number and existing part number whenever available.
Need a Caterpillar 3406 component? Request a Quote or email request@alfamarinespareparts.com.
Caterpillar 3406 Engine Overview
The Caterpillar 3406 is the inline six-cylinder member of Caterpillar's established 3400 Series diesel-engine family.
The platform has been used across heavy-duty marine propulsion, auxiliary and power-generation applications.
Different generations include:
Caterpillar 3406
Caterpillar 3406B
Caterpillar 3406C
The suffix matters because fuel-system components, turbochargers, cooling arrangements, electrical equipment and other components can differ between generations and individual engine arrangements.
The currently documented 3406C marine propulsion engine is a mechanically governed, four-stroke inline-six diesel with:
- 6 cylinders
- Inline configuration
- 14.6 L displacement
- 137.2 mm bore
- 165.1 mm stroke
- Turbocharging and aftercooling
- Mechanical governor
- 1,800 rpm rated speed
- 272–298 bkW marine propulsion output
- Heat-exchanger or keel-cooling arrangements
For information about the wider engine platform, visit our Caterpillar 3400 Series Marine Engine Parts page.
Caterpillar 3406C Technical SpecificationsSpecificationCaterpillar 3406C MarineEngine type4-stroke dieselConfigurationInline 6Cylinders6Bore137.2 mmStroke165.1 mmDisplacement14.6 LAspirationTurbocharged and aftercooledGovernorMechanicalRated speed1,800 rpmPower range272–298 bkWHorsepower365–400 bhpCoolingHeat exchanger or keel cooledApprox. dry weight1,325 kgOil change interval250 hours
These specifications apply to Caterpillar's documented 3406C marine propulsion configuration.
Older 3406 and 3406B engines can differ according to application and production specification.
Caterpillar 3406, 3406B & 3406C
The Caterpillar 3406 family spans several generations.
Caterpillar 3406
The original 3406 established the basic inline-six heavy-duty architecture used across multiple applications.
Caterpillar 3406B
The 3406B represents a later generation with revisions to engine systems and components.
Parts should be selected against the engine serial number rather than assuming that every 3406 component fits the 3406B.
Caterpillar 3406C
The 3406C is another later development of the family.
Caterpillar's marine documentation identifies the 3406C as a mechanically governed turbocharged-aftercooled commercial propulsion engine.
Because of generation differences, always provide the complete engine designation when requesting components.
Caterpillar 3406 Parts We Can Source
Alfa Marine Spare Parts can assist with a broad range of Caterpillar 3406 engine parts.
SystemTypical ComponentsFuel SystemInjectors, nozzles, injection pumps, transfer pumps and filtersCylinder ComponentsHeads, liners, pistons, rings and valvesCranktrainConnecting rods, bearings and crankshaft componentsTurbochargingTurbochargers and associated componentsCooling SystemJacket-water pumps, seawater pumps, thermostats and coolersLubricationOil pumps, oil coolers, filters and sealsAir & ExhaustAftercooler, manifold and exhaust componentsElectricalStarters, alternators, switches and sensorsOverhaulPistons, liners, bearings, gaskets, seals and rebuild parts
If you already know the required part number, browse our Marine Spare Parts Catalogue.
Caterpillar 3406 Fuel System Parts
Fuel-system requirements can include:
- Fuel injectors
- Fuel nozzles
- Fuel injection pumps
- Fuel transfer pumps
- Fuel priming pumps
- Fuel filters
- Governor components
- Fuel lines
- Injector seals
- Fuel-system gaskets
- Associated fittings
The documented marine 3406C uses a mechanically governed fuel system.
Fuel-system components can differ between 3406 generations.
A fuel component for a 3406C should therefore not automatically be selected for a 3406B or earlier 3406.
For accurate sourcing, provide:
3406 / 3406B / 3406C + Engine Serial Number + Existing Part NumberCaterpillar 3406 Fuel Injectors & Nozzles
Fuel-injection components are among the most frequently requested 3406 parts.
Requirements can include:
- Complete injectors
- Fuel nozzles
- Injector assemblies
- Injector seals
- Injection-pump components
- Fuel lines
- Delivery components
- Associated gaskets
Injection components should always be matched to the exact engine configuration.
If an existing injector or nozzle number is visible, include it with your enquiry.
Caterpillar 3406 Cylinder Head Parts
Cylinder-head requirements can include:
- Complete cylinder heads
- Intake valves
- Exhaust valves
- Valve guides
- Valve seats
- Valve springs
- Rocker components
- Cylinder-head gaskets
- Injector-related components
- O-rings
- Seals
- Associated hardware
Cylinder-head components can differ according to engine generation and serial-number range.
Caterpillar 3406 Pistons & Cylinder Liners
Internal-engine requirements can include:
- Pistons
- Piston rings
- Piston pins
- Cylinder liners
- Liner seals
- Connecting rods
- Connecting-rod bearings
- Main bearings
- Thrust components
- Gaskets
- O-rings
For an engine overhaul, prepare the parts list against the exact engine serial number and arrangement.
Caterpillar 3406 Connecting Rod & Bearing Parts
Cranktrain components can include:
- Connecting rods
- Connecting-rod bearings
- Main bearings
- Thrust bearings
- Connecting-rod bushings
- Fasteners
- Crankshaft seals
- Associated hardware
Bearing dimensions and part numbers should always be verified before ordering.
Caterpillar 3406 Crankshaft Components
Crankshaft-related requirements can include:
- Complete crankshaft
- Main bearings
- Connecting-rod bearings
- Thrust components
- Crankshaft seals
- Crankshaft gears
- Vibration damper
- Associated hardware
Because crankshaft components are high-value engine parts, complete engine identification is especially important.
Caterpillar 3406 Turbocharger Parts
The marine 3406C is turbocharged and aftercooled.
Turbocharger requirements can include:
- Complete turbocharger
- Turbocharger cartridge
- Turbine components
- Compressor components
- Bearings
- Seals
- Oil-feed components
- Oil-return components
- Intake connections
- Exhaust connections
- Gaskets
Turbocharger configuration can differ according to engine rating and generation.
Whenever possible, send both the engine serial number and turbocharger identification number.
Caterpillar 3406 Aftercooler Parts
Aftercooler requirements can include:
- Aftercooler core
- Housing
- Gaskets
- Seals
- O-rings
- Cooling connections
- Intake-air connections
- Associated hardware
The documented 3406C marine propulsion engine uses a corrosion-resistant aftercooler core.
Marine operating conditions make correct cooling-system maintenance particularly important.
Caterpillar 3406 Cooling System Parts
Marine 3406 cooling-system requirements can include:
- Jacket-water pumps
- Sea water pumps
- Raw-water pumps
- Heat exchangers
- Thermostats
- Aftercooler components
- Expansion tanks
- Oil coolers
- Cooling-water pipes
- Mechanical seals
- Gaskets
- O-rings
Caterpillar documents the 3406C with a gear-driven centrifugal jacket-water pump.
Applicable configurations can use either heat-exchanger cooling or keel cooling.
A sea water pump and heat exchanger are available as applicable marine cooling equipment.
Caterpillar 3406 Sea Water Pump
For applicable heat-exchanger-cooled installations, the raw-water system circulates seawater through the external cooling circuit.
Sea water pump requirements can include:
- Complete pump
- Impeller
- Shaft
- Bearings
- Mechanical seal
- Cover
- Gasket
- Housing
- O-rings
- Repair components
Not every 3406 installation uses the same cooling arrangement.
For example, a keel-cooled installation can differ considerably from a heat-exchanger-cooled engine.
Always provide the existing pump number when possible.
Heat Exchanger vs Keel-Cooled Caterpillar 3406
The marine 3406C can be configured for heat-exchanger cooling or keel cooling.
Heat Exchanger Cooling
In a heat-exchanger installation, raw seawater removes heat from the engine's closed coolant circuit through a heat exchanger.
This arrangement can involve:
- Sea water pump
- Heat exchanger
- Jacket-water pump
- Thermostats
- Cooling pipes
- Associated seals and gaskets
Keel Cooling
A keel-cooled installation uses an external vessel cooling circuit instead of a conventional onboard seawater heat exchanger arrangement.
Because these cooling systems differ, do not order cooling parts based only on the engine model.
Caterpillar 3406 Oil Pump & Lubrication Parts
Lubrication-system requirements can include:
- Engine oil pump
- Oil filters
- Oil cooler
- Oil pressure regulators
- Oil lines
- Oil pressure gauges
- Oil pressure sensors
- Crankshaft seals
- Gaskets
- O-rings
Correct oil pressure and lubrication are critical for protecting:
- Main bearings
- Connecting-rod bearings
- Crankshaft journals
- Camshaft components
- Pistons
- Turbocharger bearings
Caterpillar 3406 Exhaust Components
The marine 3406C uses a water-cooled exhaust manifold.
Exhaust-system requirements can include:
- Exhaust manifold
- Manifold gaskets
- Turbocharger exhaust connections
- Exhaust flange components
- Fasteners
- Seals
- Associated cooling connections
Marine exhaust components should be checked carefully for corrosion and coolant leakage.
Caterpillar 3406 Electrical Parts
Depending on engine configuration, electrical requirements can include:
- Starter motors
- Alternators
- Solenoids
- Temperature switches
- Pressure switches
- Sensors
- Gauges
- Wiring
- Instrument-panel components
Caterpillar documents the marine 3406C with available 12 V or 24 V starting and charging equipment.
Before ordering a starter or alternator, verify the vessel's electrical configuration and existing component number.
Caterpillar 3406 Overhaul Parts
A Caterpillar 3406 overhaul can require:
- Cylinder liners
- Pistons
- Piston rings
- Piston pins
- Cylinder heads
- Intake valves
- Exhaust valves
- Connecting rods
- Main bearings
- Connecting-rod bearings
- Thrust bearings
- Crankshaft components
- Camshaft components
- Fuel injectors
- Injection-system components
- Turbocharger components
- Water pumps
- Oil pumps
- Gaskets
- O-rings
- Seals
For major overhaul requirements, provide the complete engine identification before preparing the final parts list.
Caterpillar 3406 Top-End Overhaul Parts
Top-end overhaul requirements can include:
- Cylinder head
- Intake valves
- Exhaust valves
- Valve guides
- Valve seats
- Valve springs
- Rocker components
- Fuel injectors
- Injector components
- Cylinder-head gasket
- O-rings
- Seals
The exact overhaul scope should depend on inspection results, operating hours and component condition.
Caterpillar 3406 Marine Applications
The Caterpillar 3406 family has been used in demanding marine applications.
These can include:
Fishing Vessels
The inline-six format has been widely suited to fishing-vessel propulsion and auxiliary requirements.
Workboats
The 3406 has been used in commercial workboat applications requiring reliable continuous-duty diesel power.
Commercial Propulsion
The 3406C is specifically documented by Caterpillar as a commercial marine propulsion engine.
Tugboats
Applicable 3406 configurations can be found in working vessels and auxiliary applications.
Auxiliary Engines
The 3406 platform has also been used for auxiliary and power-generation duties.
Marine Generator Sets
Applicable 3406 configurations have supported onboard power-generation requirements.
Caterpillar 3406 vs 3408
Both engines belong to the Caterpillar 3400 Series, but their configurations differ.
EngineConfigurationCylindersCaterpillar 3406Inline6Caterpillar 3408V8
Do not assume components are interchangeable simply because the engines belong to the same family.
Fuel-system, cooling, turbocharger and internal-engine components should be verified individually.
Caterpillar 3406 vs 3412
The 3406 and 3412 belong to the same wider 3400 family.
EngineConfigurationCylindersCaterpillar 3406Inline6Caterpillar 3412V12
The 3412 has twice the cylinder count and a substantially different engine layout.
For the V12 engine, visit our Caterpillar 3412 Marine Engine Parts page.
Caterpillar 3406 vs Caterpillar 3500 Series
The Caterpillar 3406 should not be confused with larger 3500-family engines.
Examples of the 3500 family include:
- Caterpillar 3508
- Caterpillar 3512
- Caterpillar 3516
For larger-engine requirements, visit our Caterpillar 3512 Marine Engine Parts or Caterpillar 3516 Marine Engine Parts pages.
Searching for a Caterpillar 3406 Part?
When requesting a component, send:
Engine model: Caterpillar 3406 / 3406B / 3406C
Engine serial number:
Serial-number prefix:
Arrangement number:
Existing part number:
Part description:
Quantity:
Required condition:
Photographs:
This information is particularly important for:
- Fuel injectors
- Injection pumps
- Turbochargers
- Cylinder heads
- Pistons
- Cylinder liners
- Bearings
- Sea water pumps
- Jacket-water pumps
- Oil pumps
- Starters
- Alternators
Browse our Caterpillar Engine Parts Catalogue or Marine Spare Parts Catalogue if you already have a part number.
Why the Caterpillar 3406 Serial Number Matters
A request saying:
“I need Caterpillar 3406 parts”
identifies the general engine family, but it may not provide enough information for final parts selection.
The engine may be:
- 3406
- 3406B
- 3406C
- A specific serial-number range
- Marine propulsion
- Auxiliary
- Generator application
- Heat-exchanger cooled
- Keel cooled
- A particular engine arrangement
The safest identification sequence is:
Complete Model + Serial Number + Arrangement Number + Existing Part Number
This helps reduce incorrect component selection.
Why Source Caterpillar 3406 Parts Through Alfa Marine Spare Parts?
Alfa Marine Spare Parts assists shipowners, ship managers, shipyards, marine engineers, repair companies, engine rebuilders and purchasing departments with sourcing Caterpillar 3406 marine engine parts.
Depending on availability, we can assist with:
- Routine maintenance parts
- Fuel-system components
- Cylinder components
- Internal-engine parts
- Turbocharger components
- Cooling-system parts
- Sea water pumps
- Jacket-water pumps
- Lubrication components
- Electrical parts
- Top-end overhaul parts
- Major overhaul components
- Genuine components
- OEM components
- Replacement components
- Applicable Reman options
For the complete engine family, visit our Caterpillar 3400 Series Marine Engine Parts page.
Alfa Marine Spare Parts is an independent marine spare-parts supplier and is not an official Caterpillar dealer.
Frequently Asked Questions About Caterpillar 3406Is the Caterpillar 3406 a Six-Cylinder Engine?
Yes. The 3406 uses an inline six-cylinder configuration.
What Is the Caterpillar 3406C Displacement?
The documented marine 3406C has approximately 14.6 litres of displacement.
What Is the Caterpillar 3406C Power Range?
Caterpillar currently lists its marine commercial propulsion version at 365–400 bhp, or 272–298 bkW.
What Speed Does the Caterpillar 3406C Run At?
The documented marine propulsion configuration is rated at 1,800 rpm.
Is the Caterpillar 3406C Turbocharged?
Yes. The documented marine 3406C is turbocharged and aftercooled.
Is the Caterpillar 3406C Electronically Controlled?
The currently documented marine propulsion version is mechanically governed.
Does the Caterpillar 3406 Use a Sea Water Pump?
Applicable heat-exchanger-cooled marine installations can use a sea water pump.
Keel-cooled installations can use a different cooling arrangement.
Are 3406, 3406B and 3406C Parts the Same?
Do not assume so.
Parts can differ according to engine generation, serial number, arrangement and application.
Can You Supply Caterpillar 3406 Overhaul Parts?
Yes. Alfa Marine Spare Parts can assist with applicable pistons, cylinder liners, bearings, cylinder components, fuel-system parts, turbocharger components, cooling-system parts, gaskets, seals and other overhaul requirements, subject to availability.
Related Caterpillar Pages
Caterpillar 3400 Series Marine Engine Parts
Caterpillar 3412 Marine Engine Parts
Caterpillar Marine Engine Parts & Rebuild Kits
Caterpillar Engine Parts Catalogue
Caterpillar 3512 Marine Engine Parts
Caterpillar 3516 Marine Engine Parts
Caterpillar C32 Marine Engine Parts
Request Caterpillar 3406 Marine Engine Parts
Looking for Caterpillar 3406, 3406B or 3406C marine engine parts, maintenance spares or overhaul components?
Send us:
Engine model: Caterpillar 3406 / 3406B / 3406C
Engine serial number:
Serial-number prefix:
Arrangement number:
Existing part number:
Part description:
Quantity:
Required condition: Genuine / OEM / Replacement / Reman where applicable
Vessel name:
Current vessel location:
Delivery destination:
Required date:
If the part number is unknown, include clear photographs of the engine identification plate and existing component.
Email: request@alfamarinespareparts.com
For the complete family, visit our Caterpillar 3400 Series Marine Engine Parts page.
For the V12 member of the family, visit our Caterpillar 3412 Marine Engine Parts page.
You can also browse our Caterpillar Marine Engine Parts & Rebuild Kits and Marine Spare Parts Catalogue.
Worldwide parts supply for commercial vessels, fishing vessels, workboats, shipyards, engine rebuilders and marine repair companies.