Caterpillar C12 Marine Engine Parts & Spares
Alfa Marine Spare Parts supplies Caterpillar C12 marine engine parts and spares for commercial vessels, workboats, fishing vessels, recreational craft, yachts and marine propulsion applications.
We source genuine, OEM, replacement and applicable Reman Caterpillar C12 parts, subject to availability, for scheduled maintenance, engine repairs, top-end overhaul and complete engine rebuild requirements.
Our sourcing capabilities cover fuel injectors, fuel-system components, cylinder heads, pistons, piston rings, cylinder components, connecting rods, bearings, turbochargers, aftercooler parts, sea water pumps, jacket-water pumps, heat exchangers, oil pumps, oil coolers, electronic control components, sensors, starters, alternators, gaskets, seals and overhaul components.
The Caterpillar C12 is a 12-litre inline six-cylinder four-stroke diesel engine developed for commercial and recreational marine propulsion applications.
For other Caterpillar engines, visit our Caterpillar Marine Engine Parts & Rebuild Kits page.
For correct parts identification, provide the complete engine model, engine serial number, serial-number prefix, arrangement number and existing part number whenever available.
Need a specific Caterpillar C12 component? Request a Quote or email request@alfamarinespareparts.com.
Caterpillar C12 Marine Engine Overview
The Caterpillar C12 is an inline six-cylinder, four-stroke marine diesel engine designed for commercial and recreational propulsion applications.
The engine uses a 130 mm cylinder bore and 150 mm piston stroke, producing a displacement of approximately 12 litres.
Caterpillar commercial marine C12 configurations cover approximately 340–490 bhp (254–366 bkW) at engine speeds between 1,800 and 2,300 rpm.
The engine uses turbocharging and aftercooling together with electronically controlled unit injection.
Caterpillar produced the C12 in multiple ratings and configurations, so individual engines can differ according to:
- Engine serial number
- Serial-number prefix
- Arrangement number
- Power rating
- Rated engine speed
- Duty classification
- Emissions specification
- Turbocharger configuration
- Cooling-system arrangement
- Electronic-control specification
- Vessel installation
- Production revision
For this reason, replacement components should always be identified against the individual engine.
Caterpillar C12 Technical SpecificationsSpecificationCaterpillar C12 MarineManufacturerCaterpillarEngine modelC12Engine type4-stroke dieselCylinder configurationInline 6Number of cylinders6Cylinder bore130 mmPiston stroke150 mmDisplacement12.0 LPower range340–490 bhpPower range254–366 bkWEngine speed1,800–2,300 rpmAspirationTurbocharged and aftercooledFuel systemElectronically controlled unit injectionEngine controlElectronicRotation from flywheel endCounterclockwiseApplicationsCommercial and recreational marine propulsionParts identificationSerial number and arrangement dependent
Exact rating, emissions configuration, cooling equipment and installed components depend on the individual C12 engine arrangement.
Caterpillar C12 Marine Engine Parts
Alfa Marine Spare Parts can assist with a broad selection of Caterpillar C12 engine parts for routine maintenance, corrective repairs and complete overhaul requirements.
Parts categories include:
- Cylinder components
- Internal engine parts
- Fuel-system components
- Fuel injectors
- Turbocharger components
- Aftercooler parts
- Cooling-system components
- Lubrication-system parts
- Electronic-control components
- Electrical parts
- Gaskets and seals
- Maintenance parts
- Overhaul components
You can also browse our Marine Spare Parts Catalogue.
Caterpillar C12 Cylinder Head Parts
Cylinder-head requirements can include:
- Complete cylinder heads
- Intake valves
- Exhaust valves
- Valve guides
- Valve seats
- Valve springs
- Rocker components
- Injector-related components
- Cylinder-head sealing components
- O-rings
- Seals
- Fasteners
For cylinder-head repairs or top-end overhaul requirements, provide the complete engine serial number and existing component numbers whenever available.
Caterpillar C12 Pistons & Internal Engine Parts
Internal-engine requirements can include:
- Pistons
- Piston rings
- Piston pins
- Connecting rods
- Connecting-rod bushings
- Main bearings
- Connecting-rod bearings
- Thrust bearings
- Crankshaft components
- Camshaft components
- Timing components
- Gaskets
- O-rings
- Seals
Major internal components should always be verified against the engine serial number and arrangement.
Caterpillar C12 Fuel System Parts
The Caterpillar C12 marine engine uses an electronically controlled unit-injection fuel system.
Fuel-system requirements can include:
- Fuel injectors
- Injector components
- Injector seals
- Fuel transfer pumps
- Fuel priming components
- Primary fuel filters
- Secondary fuel filters
- Fuel-water separator components
- Fuel pressure components
- Fuel lines
- Fuel fittings
- Electronic-control components
- Sensors
- Wiring
- Connectors
- Fuel-system gaskets
Fuel-system components can vary according to engine serial number, arrangement and production revision.
Caterpillar C12 Fuel Injectors
For Caterpillar C12 injector requirements, provide:
Engine model: Caterpillar C12
Application: Marine
Engine serial number:
Serial-number prefix:
Arrangement number:
Existing injector part number:
Quantity:
This information helps identify the correct injector specification and any applicable superseded or Reman part number.
Do not select a C12 injector using the engine model alone.
Caterpillar C12 Turbocharger Parts
Caterpillar C12 marine engines use turbocharging and aftercooling.
Turbocharger requirements can include:
- Complete turbochargers
- Applicable Reman turbochargers
- Turbocharger cartridges
- Compressor components
- Turbine components
- Bearings
- Seals
- Oil-feed components
- Oil-return components
- Cooling components
- Intake connections
- Exhaust connections
- Mounting gaskets
Correct turbocharger selection depends on the individual C12 rating and engine arrangement.
Provide:
C12 + Engine Serial Number + Existing Turbocharger NumberCaterpillar C12 Aftercooler Parts
The Caterpillar C12 marine engine uses an aftercooling system as part of its air-intake arrangement.
Applicable requirements can include:
- Aftercooler assemblies
- Aftercooler cores
- Housings
- End covers
- Gaskets
- O-rings
- Seals
- Cooling connections
- Air connections
- Mounting components
Marine C12 configurations use sea-water aftercooling arrangements.
The exact aftercooler components should always be checked against the individual engine.
Caterpillar C12 Cooling System Parts
Marine cooling-system requirements can include:
- Sea water pumps
- Raw-water pumps
- Jacket-water pumps
- Heat exchangers
- Aftercooler components
- Oil coolers
- Thermostats
- Expansion-tank components
- Cooling pipes
- Hoses
- Pump shafts
- Mechanical seals
- Bearings
- Gaskets
- O-rings
Correct cooling-system operation is particularly important in marine applications because the engine's jacket-water, aftercooling and raw-water circuits must operate together correctly.
Caterpillar C12 Sea Water Pump Parts
For applicable Caterpillar C12 marine installations, we can assist with:
- Complete sea water pumps
- Raw-water pumps
- Pump housings
- Pump shafts
- Mechanical seals
- Bearings
- Pump covers
- Gaskets
- O-rings
- Repair components
Correct pump identification can depend on:
- Engine serial number
- Arrangement number
- Existing pump number
- Engine rating
- Cooling configuration
- Vessel installation
Do not assume every C12 marine configuration uses identical sea water pump components.
Caterpillar C12 Heat Exchanger Parts
Marine heat-exchanger requirements can include:
- Complete heat exchangers
- Heat exchanger cores
- End covers
- Expansion-tank components
- Gaskets
- O-rings
- Seals
- Cooling connections
- Mounting components
Heat exchanger components should be identified against the individual engine and cooling-system arrangement.
Caterpillar C12 Oil Pump & Lubrication Parts
Lubrication-system requirements can include:
- Engine oil pumps
- Oil filters
- Oil coolers
- Oil-pressure regulators
- Oil-pressure sensors
- Oil lines
- Oil-pan components
- Crankshaft seals
- Gaskets
- O-rings
Correct lubrication is essential for protecting the crankshaft, bearings, pistons, camshaft and turbocharger during continuous marine operation.
Caterpillar C12 Crankshaft & Bearing Parts
Crankshaft and bearing requirements can include:
- Crankshafts
- Main bearings
- Connecting-rod bearings
- Thrust bearings
- Connecting rods
- Connecting-rod bushings
- Crankshaft seals
- Crankshaft gears
- Vibration-damper components
- Associated hardware
For major internal-engine requirements, provide:
Engine Serial Number + Arrangement Number + Existing Part NumberCaterpillar C12 Camshaft & Timing Parts
Timing-system requirements can include:
- Camshafts
- Camshaft bearings
- Camshaft gears
- Timing gears
- Gear-train components
- Covers
- Bushings
- Fasteners
- Gaskets
- Seals
Correct components should always be identified against the individual engine arrangement.
Caterpillar C12 Electronic Control Parts
Electronic control is an important part of the Caterpillar C12 marine engine.
Requirements can include:
- Electronic control modules
- Engine sensors
- Pressure sensors
- Temperature sensors
- Speed sensors
- Wiring harnesses
- Connectors
- Engine monitoring components
- Diagnostic components
- Switches
- Senders
Caterpillar's C12 marine control system supports electronic governing, engine monitoring, diagnostics and fault logging.
Electronic components should always be identified using the complete engine serial number and existing component number.
Caterpillar C12 Starter & Alternator Parts
Electrical requirements can include:
- Starter motors
- Starter solenoids
- Alternators
- Charging-system components
- Sensors
- Switches
- Wiring harnesses
- Connectors
- Monitoring components
Before ordering electrical components, verify:
- Engine serial number
- Existing part number
- System voltage
- Mounting arrangement
- Electrical connections
Caterpillar C12 Intake & Exhaust Parts
Air-intake and exhaust requirements can include:
- Intake manifolds
- Exhaust manifolds
- Turbocharger connections
- Aftercooler components
- Air-intake pipes
- Exhaust connections
- Exhaust elbows
- Gaskets
- Seals
- Clamps
- Mounting hardware
The exact configuration can vary according to engine rating and vessel installation.
Caterpillar C12 Gaskets & Seals
Gasket and sealing requirements can include:
- Cylinder-head sealing components
- Rocker-cover gaskets
- Intake-manifold gaskets
- Exhaust-manifold gaskets
- Turbocharger gaskets
- Aftercooler seals
- Oil-pan gaskets
- Water-pump gaskets
- Crankshaft seals
- Oil seals
- Injector seals
- O-rings
Complete gasket requirements can also be prepared together with associated overhaul components.
Caterpillar C12 Overhaul Parts
For a Caterpillar C12 marine engine overhaul, Alfa Marine Spare Parts can assist with applicable:
- Pistons
- Piston rings
- Piston pins
- Cylinder components
- Cylinder heads
- Intake valves
- Exhaust valves
- Connecting rods
- Main bearings
- Connecting-rod bearings
- Thrust bearings
- Crankshaft components
- Camshaft components
- Fuel injectors
- Turbocharger components
- Aftercooler parts
- Cooling-system components
- Oil pumps
- Oil cooler parts
- Electronic components
- Gaskets
- O-rings
- Seals
For major overhaul requirements, send the complete engine identification together with the required parts list.
Caterpillar C12 Top-End Overhaul Parts
Top-end overhaul requirements can include:
- Cylinder-head components
- Intake valves
- Exhaust valves
- Valve guides
- Valve seats
- Valve springs
- Rocker components
- Fuel injectors
- Injector seals
- Cylinder-head sealing components
- O-rings
- Seals
The final overhaul scope should be determined according to engine condition, service history and inspection results.
Caterpillar C12 Reman Parts
Applicable Caterpillar Reman components may be available for selected C12 engine requirements.
Depending on the engine serial number and component, requirements can include:
- Fuel-system components
- Fuel injectors
- Turbochargers
- Cylinder-head components
- Starters
- Alternators
- Other major engine components
Reman compatibility should always be checked against:
C12 + Engine Serial Number + Existing Part NumberCaterpillar C12 Marine Applications
The Caterpillar C12 is designed for marine propulsion applications.
Depending on rating and configuration, applications can include:
- Commercial vessels
- Workboats
- Fishing vessels
- Passenger vessels
- Recreational boats
- Yachts
- Utility craft
- Other marine propulsion installations
Caterpillar offers multiple C12 ratings to support different marine duty requirements.
Caterpillar C12 Commercial Marine Engine
The commercial Caterpillar C12 marine engine is available across approximately:
340–490 bhp (254–366 bkW)
with applicable rated speeds between:
1,800–2,300 rpm
The exact rating should always be confirmed using the engine serial number and arrangement.
Commercial and recreational configurations should not automatically be treated as identical when selecting replacement parts.
Caterpillar C12 vs C12 ACERT
The Caterpillar C12 and C12 ACERT should be listed separately in your marine-engine catalogue.
Both share the principal:
- Inline six-cylinder configuration
- 12-litre displacement
- 130 mm bore
- 150 mm stroke
However, the current commercial C12 range is rated approximately 340–490 bhp, while Caterpillar's high-performance C12 ACERT marine engine is available at approximately 660–705 bhp at 2,300 rpm.
Differences in rating and engine configuration can affect:
- Fuel-system components
- Turbocharger components
- Aftercooling
- Electronic controls
- Cooling-system components
- Exhaust components
- Engine calibration
- Supporting parts
Parts should therefore never be assumed interchangeable simply because both engines carry the C12 designation.
Caterpillar C12 vs C18
The Caterpillar C12 and C18 are separate marine engine platforms.
The C12 is a 12-litre inline six-cylinder engine, while the C18 belongs to a larger displacement class.
Differences affect internal components, fuel systems, turbochargers, cooling systems, electronics and overhaul components.
For the larger engine platform, visit our Caterpillar C18 Marine Engine Parts page.
Caterpillar C12 Parts Identification
Correct parts identification is essential because Caterpillar produced multiple C12 marine ratings and arrangements.
When requesting parts, provide:
Engine model: Caterpillar C12
Application: Marine
Engine serial number:
Serial-number prefix:
Arrangement number:
Existing part number:
Part description:
Quantity:
For fuel injectors, turbochargers, pumps, electronic modules, starters and alternators, clear photographs of the existing component can also assist with identification.
The preferred identification sequence is:
Caterpillar C12 Marine + Engine Serial Number + Arrangement Number + Existing Part NumberWhy Source Caterpillar C12 Parts From Alfa Marine Spare Parts?
Alfa Marine Spare Parts supports shipowners, yacht operators, ship managers, shipyards, marine engineers, purchasing departments, repair companies and engine rebuilders with Caterpillar C12 marine engine parts and spares.
Depending on availability, we can assist with:
- Scheduled maintenance parts
- Fuel injectors
- Fuel-system components
- Electronic-control components
- Cylinder components
- Internal engine parts
- Turbocharger components
- Aftercooler parts
- Cooling-system components
- Sea water pumps
- Heat exchanger parts
- Lubrication-system components
- Electrical components
- Top-end overhaul parts
- Complete overhaul requirements
- Genuine parts
- OEM parts
- Replacement parts
- Applicable Reman parts
You can also browse our Caterpillar Marine Engine Parts & Rebuild Kits, Caterpillar Engine Parts Catalogue and Marine Spare Parts Catalogue.
Alfa Marine Spare Parts is an independent marine spare-parts supplier and is not an official Caterpillar dealer.
Frequently Asked QuestionsIs the Caterpillar C12 a Marine Engine?
Yes. The Caterpillar C12 is a dedicated marine propulsion engine available for commercial and recreational vessel applications.
How Many Cylinders Does the Caterpillar C12 Have?
The Caterpillar C12 is an inline six-cylinder four-stroke diesel engine.
What Is the Caterpillar C12 Displacement?
The Caterpillar C12 has a displacement of approximately 12 litres.
What Are the Caterpillar C12 Bore and Stroke?
The C12 uses a 130 mm bore and 150 mm stroke.
How Much Power Does the Caterpillar C12 Produce?
Current Caterpillar commercial marine specifications list approximately 340–490 bhp (254–366 bkW).
What Is the Caterpillar C12 Engine Speed?
Applicable commercial marine ratings operate between approximately 1,800 and 2,300 rpm.
Is the Caterpillar C12 Turbocharged?
Yes. Caterpillar specifies the C12 marine engine as turbocharged and aftercooled.
Does the Caterpillar C12 Use Electronic Fuel Injection?
The C12 marine engine uses an electronically controlled unit-injection fuel system.
Is C12 the Same as C12 ACERT?
No.
They should be treated separately for parts identification. The high-performance C12 ACERT is available at significantly higher output ratings than the standard commercial C12 configurations.
Can You Supply Caterpillar C12 Fuel Injectors?
Yes. We can assist with applicable fuel injectors and related fuel-system components, subject to correct identification and availability.
Can You Supply Caterpillar C12 Turbochargers?
Yes. We can assist with applicable turbochargers and associated components.
Provide the engine serial number and existing turbocharger number whenever available.
Can You Supply Caterpillar C12 Sea Water Pumps?
Yes. We can assist with applicable C12 marine sea water pumps and related cooling-system components.
Provide the engine serial number and existing pump number for accurate identification.
Can You Supply Caterpillar C12 Overhaul Parts?
Yes. Depending on availability, we can assist with pistons, rings, bearings, cylinder-head components, injectors, turbocharger components, cooling-system parts, gaskets, seals and other overhaul requirements.
Related Caterpillar Engine Pages
Caterpillar C9 Marine Engine Parts
Caterpillar C15 Marine Engine Parts
Caterpillar C18 Marine Engine Parts
Caterpillar C32 Marine Engine Parts
Caterpillar 3116 Marine Engine Parts
Caterpillar 3126 Marine Engine Parts
Caterpillar Marine Engine Parts & Rebuild Kits
Caterpillar Engine Parts Catalogue
Request Caterpillar C12 Marine Engine Parts
Looking for Caterpillar C12 marine engine parts, maintenance spares or overhaul components?
Send us:
Engine model: Caterpillar C12
Application: Marine
Engine serial number:
Serial-number prefix:
Arrangement number:
Existing part number:
Part description:
Quantity:
Required condition: Genuine / OEM / Replacement / Reman where applicable
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
You can also browse our Caterpillar Marine Engine Parts & Rebuild Kits.
Worldwide supply of Caterpillar C12 parts for commercial vessels, workboats, fishing vessels, yachts, shipyards, marine repair companies and engine rebuilders.