Wärtsilä 6L25DF Marine Engine Parts & Spare Parts
Alfa Marine Spare Parts supplies Wärtsilä 6L25DF marine engine parts and spare parts for commercial vessels, marine propulsion systems, auxiliary engines, diesel-electric installations and power-generation applications.
We source genuine, OEM and replacement Wärtsilä 6L25DF parts for scheduled maintenance, engine repairs and major overhaul requirements.
Our sourcing capabilities cover cylinder components, internal engine parts, dual-fuel equipment, fuel and injection components, gas-system related engine components, cooling and lubrication parts, pumps, valves, bearings, gaskets, seals, sensors and other Wärtsilä engine spares.
For accurate parts identification, provide the complete engine designation, engine serial number and existing part number whenever available.
Need a specific component or complete overhaul requirement? Request a Quote or email request@alfamarinespareparts.com.
Wärtsilä 6L25DF Engine Overview
The Wärtsilä 6L25DF is the six-cylinder inline dual-fuel configuration within the Wärtsilä 25 medium-speed engine family.
The engine uses a 250 mm cylinder bore and 340 mm piston stroke and operates at nominal engine speeds of 900 or 1000 rpm, depending on the engine specification and application.
The 6L25DF is designed for dual-fuel operation, supporting operation with gaseous fuel and liquid fuel according to the applicable engine configuration and operating mode.
This makes the Wärtsilä 6L25DF suitable for marine and power-generation applications where fuel flexibility is required.
Individual engine specifications and installed components can vary according to production revision, vessel application, emissions configuration, fuel arrangement and engine installation.
Replacement parts should therefore always be selected using the complete Wärtsilä 6L25DF engine designation, serial number and existing part number whenever available.
For information about the wider engine platform, visit our Wärtsilä 25 Engine Parts, Spares & Overhaul Components page.
For the diesel six-cylinder configuration, visit our Wärtsilä 6L25 Engine Parts, Spares & Overhaul Components page.
Wärtsilä 6L25DF Technical SpecificationsSpecificationWärtsilä 6L25DFEngine type4-stroke medium-speed dual-fuelCylinder configuration6-cylinder inlineCylinder bore250 mmPiston stroke340 mmEngine speed900 / 1000 rpmOutput per cylinder315 / 345 kWRated engine outputApprox. 1,890 / 2,070 kWPiston speed10.2 / 11.3 m/sFuel configurationDual-fuelApplicationsMarine propulsion, diesel-electric and power generation
Exact output and technical specifications can vary according to engine version, application, fuel configuration, emissions specification and installation.
Wärtsilä 6L25DF Spare Parts & Components
We can source a broad selection of Wärtsilä 6L25DF spare parts for routine service, corrective maintenance and planned engine overhaul work.
Requirements can range from individual replacement components and consumable service parts to larger overhaul packages.
The dual-fuel configuration makes accurate identification particularly important. Fuel, gas, combustion, electronic and control-system components should always be verified against the complete engine specification.
Wärtsilä 6L25DF Cylinder & Internal Engine Parts
Major internal engine components operate under high mechanical and thermal loads and require correct specification during maintenance and overhaul work.
Wärtsilä 6L25DF internal engine parts can include:
- Cylinder liners
- Pistons
- Piston crowns
- Piston skirts
- Piston rings
- Piston pins
- Connecting rods
- Connecting-rod bearings
- Main bearings
- Thrust bearings
- Crankshaft components
- Cylinder-head components
- Valve guides
- Valve seats
- Intake valves
- Exhaust valves
When requesting major internal components, provide the engine serial number and existing component part number whenever possible.
Parts should not automatically be assumed to interchange with the diesel Wärtsilä 6L25 engine.
Wärtsilä 6L25DF Cylinder Head Parts
The cylinder-head assembly contains components required for combustion sealing, intake and exhaust flow, fuel delivery and correct valve operation.
We can assist with sourcing Wärtsilä 6L25DF cylinder-head parts including:
- Complete cylinder heads
- Cylinder-head components
- Intake valves
- Exhaust valves
- Valve seats
- Valve guides
- Valve springs
- Valve rotators
- Rocker-arm components
- Sealing rings
- O-rings
- Cylinder-head gaskets
- Fuel-system mounting components
Cylinder-head components should always be checked against the individual engine because revisions and differences can occur between engine generations and fuel configurations.
Wärtsilä 6L25DF Pistons, Liners & Piston Rings
Pistons, piston rings and cylinder liners are major components commonly inspected or replaced during scheduled medium-speed engine overhaul work.
We can source requirements including:
- Cylinder liners
- Pistons
- Piston crowns
- Piston skirts
- Complete piston assemblies
- Compression rings
- Oil-control rings
- Piston pins
- Retaining rings
- Cylinder-liner sealing rings
- Piston cooling components
- Connecting rods
- Connecting-rod bearings
When requesting piston or liner components, provide the complete engine serial number, existing part number and required quantity.
For planned overhaul requirements, sending your complete parts list can also help identify related seals, bearings, gaskets and consumable components.
Wärtsilä 6L25DF Dual-Fuel & Fuel Injection Parts
The fuel system is one of the most important areas where the Wärtsilä 6L25DF differs from the diesel 6L25 configuration.
Dual-fuel operation requires equipment associated with gaseous-fuel operation and liquid-fuel operation.
Depending on the individual engine specification, requirements can include:
- Fuel injection components
- Fuel injectors
- Injector components
- Fuel pumps
- Pilot-fuel components
- High-pressure fuel components
- Fuel delivery pipes
- Fuel-return components
- Fuel filters
- Fuel-system valves
- Sealing components
- Gaskets
- O-rings
- Dual-fuel related engine components
Fuel-system components should always be selected using the 6L25DF designation, engine serial number and existing part number.
Do not assume that a fuel-system component used on a Wärtsilä 6L25 diesel engine is suitable for the 6L25DF.
Wärtsilä 6L25DF Gas System Components
Gas operation introduces additional equipment and control requirements compared with a conventional diesel-only engine.
Depending on the individual engine and installation, requirements can include:
- Gas admission components
- Gas-system valves
- Control valves
- Pressure-related components
- Temperature-related components
- Sensors
- Sealing components
- O-rings
- Gaskets
- Gas-system related engine hardware
Gas-system components require particularly careful identification.
Provide the complete engine serial number, component identification and existing part number whenever available.
Wärtsilä 6L25DF Cooling System Parts
The cooling system controls temperatures around the cylinders, cylinder heads, lubricating oil, charge air and other heat-sensitive engine components.
Available Wärtsilä 6L25DF cooling system parts can include:
- Cooling-water pumps
- Water-pump components
- Pump repair components
- Thermostatic valves
- Heat-exchanger components
- Charge-air cooler components
- Cooling-water piping components
- Cooling-system valves
- Mechanical seals
- Gaskets
- O-rings
- Temperature sensors
Cooling-system arrangements can differ according to the vessel and engine installation. Pump, valve and cooler components should therefore be verified carefully before ordering.
Wärtsilä 6L25DF Lubrication System Parts
The lubrication system protects bearings, crankshaft journals, piston components and other heavily loaded engine surfaces.
We can assist with sourcing:
- Lubricating-oil pumps
- Oil-pump repair components
- Oil filters
- Filter elements
- Pressure-regulating valves
- Oil cooler components
- Oil pipes
- Sealing rings
- Gaskets
- Bearings
- Oil pressure sensors
For oil-pump or lubrication-system requirements, provide any visible part number, casting number or equipment identification.
Wärtsilä 6L25DF Bearings & Crankshaft Components
Bearing condition and correct clearances are particularly important during major engine overhaul work.
Parts requirements can include:
- Main bearings
- Connecting-rod bearings
- Big-end bearing shells
- Thrust bearings
- Crankshaft components
- Connecting rods
- Bushings
- Fasteners
- Bearing-related seals
Bearing components should be matched to the individual engine specification and should not be selected solely according to the general Wärtsilä 25 engine family.
Wärtsilä 6L25DF Turbocharger, Air Intake & Exhaust Parts
Correct charge-air delivery and exhaust flow contribute to combustion performance and engine efficiency across the applicable operating modes.
We can assist with components associated with:
- Turbochargers
- Turbocharger repair components
- Turbocharger cartridges
- Charge-air coolers
- Air-intake components
- Exhaust valves
- Exhaust manifolds
- Expansion joints
- Exhaust piping components
- Air filters
- Gaskets
- Seals
- Temperature sensors
- Pressure sensors
For turbocharger requirements, provide the turbocharger manufacturer, complete model, serial number and existing part number whenever available.
Do not select a turbocharger or repair component based only on the Wärtsilä 6L25DF engine designation.
Wärtsilä 6L25DF Pumps & Pump Parts
Various pumps are used throughout the engine and its supporting systems.
Depending on the individual engine installation, requirements can include:
- Cooling-water pumps
- Lubricating-oil pumps
- Fuel pumps
- Circulation pumps
- Pump shafts
- Impellers
- Pump bearings
- Mechanical seals
- Pump housings
- Repair components
- Gaskets
- O-rings
Always verify the actual pump identification because different installations within the same engine family can use different auxiliary equipment.
Wärtsilä 6L25DF Gaskets, Seals & O-Rings
Routine maintenance and major overhaul work normally require replacement sealing components.
We can source requirements including:
- Cylinder-head gaskets
- Cylinder-liner seals
- O-rings
- Oil seals
- Water seals
- Mechanical seals
- Exhaust gaskets
- Intake gaskets
- Pump gaskets
- Valve-cover gaskets
- Fuel-system seals
- Overhaul sealing components
- Gasket and seal requirements
When possible, provide the complete scope of the planned repair or overhaul so related consumable components can be identified together.
Wärtsilä 6L25DF Sensors, Controls & Electrical Components
Dual-fuel engine operation depends heavily on accurate monitoring and engine control.
Wärtsilä 6L25DF electrical and monitoring requirements can include:
- Temperature sensors
- Pressure sensors
- Speed sensors
- Engine monitoring components
- Fuel-system sensors
- Gas-system sensors
- Wiring components
- Solenoids
- Switches
- Control-system components
- Alarm components
- Shutdown-system components
Electrical and electronic components require particularly careful identification because specifications can vary between engine and control-system generations.
Provide the complete engine serial number and existing component reference whenever requesting electronic or control-related parts.
Wärtsilä 6L25DF Overhaul Parts
For planned engine overhaul work, Alfa Marine Spare Parts can assist with individual components or larger Wärtsilä 6L25DF overhaul parts requirements.
Typical requirements may include:
- Cylinder liners
- Pistons
- Piston rings
- Main bearings
- Connecting-rod bearings
- Cylinder-head components
- Intake and exhaust valves
- Fuel-system components
- Dual-fuel components
- Pump components
- Gaskets
- O-rings
- Seals
- Filters
- Turbocharger components
- Sensors and monitoring components
For larger overhaul projects, send your complete BOM, spare-parts list or required part-number list for review.
Providing the complete requirement can also help identify smaller consumable components needed during disassembly and reassembly.
Wärtsilä 6L25DF Marine & Power Generation Applications
The Wärtsilä 25DF platform provides dual-fuel capability for marine and power-generation duties.
Depending on the individual engine and installation, Wärtsilä 6L25DF applications can include:
- Marine propulsion
- Diesel-electric propulsion
- Marine generating sets
- Auxiliary power generation
- Gas-fuelled vessel applications
- Merchant vessels
- Work vessels
- Offshore applications
- Specialized commercial vessels
- Power-generation installations
The actual engine and vessel installation should always be considered when identifying auxiliary equipment, fuel-system components, pumps, coolers, filters and control components.
Wärtsilä 6L25DF vs Wärtsilä 6L25
The Wärtsilä 6L25DF and Wärtsilä 6L25 belong to the wider Wärtsilä 25 engine platform, but they should not be treated as identical engines for spare-parts selection.
The 6L25DF is a dual-fuel configuration, while the 6L25 is the diesel configuration.
Important differences can exist in:
- Fuel-system components
- Dual-fuel equipment
- Gas-system components
- Combustion-related components
- Engine controls
- Sensors
- Valves
- Monitoring equipment
- Associated piping and sealing components
Some mechanical components may belong to the same wider engine platform, but this should never be interpreted as automatic parts interchangeability.
Always specify whether the engine is:
Wärtsilä 6L25DF
or
Wärtsilä 6L25
when requesting parts.
For the diesel version, visit our Wärtsilä 6L25 Engine Parts, Spares & Overhaul Components page.
Related Wärtsilä 25 Engine Models
The Wärtsilä 6L25DF belongs to the wider Wärtsilä 25 medium-speed engine platform.
Related diesel configurations include:
Related dual-fuel configurations include:
- Wärtsilä 6L25DF
- Wärtsilä 7L25DF
- Wärtsilä 8L25DF
- Wärtsilä 9L25DF
These configurations belong to the wider Wärtsilä 25 platform but should not be considered interchangeable for parts selection.
Individual components can differ according to cylinder configuration, engine generation, fuel system, control system, emissions specification and installation.
For information about the complete engine platform, visit our Wärtsilä 25 Engine Parts, Spares & Overhaul Components page.
How to Identify the Correct Wärtsilä 6L25DF Parts
Accurate engine identification is particularly important when sourcing dual-fuel engine components.
Whenever possible, provide:
Engine manufacturer: Wärtsilä
Engine model: 6L25DF
Engine serial number:
Existing part number:
Part description:
Quantity:
Required condition: Genuine / OEM / Replacement
Delivery destination:
For fuel, gas and electronic components, include any available equipment model, manufacturer, serial number or identification plate information.
Photographs of the existing component, equipment identification plates, technical drawings and spare-parts catalogue references can also assist with identification.
Do not rely only on descriptions such as “Wärtsilä 6L25DF injector,” “6L25DF gas valve,” “6L25DF water pump” or “6L25DF turbocharger.”
Different engine arrangements and production revisions can use different components.
Genuine, OEM & Replacement Wärtsilä 6L25DF Parts
Depending on the individual requirement and availability, sourcing options can include:
Genuine parts – supplied under the original manufacturer brand where available.
OEM parts – components sourced through applicable original-equipment manufacturing channels where identifiable.
Replacement parts – suitable alternative components for applicable maintenance, repair and overhaul requirements.
For critical dual-fuel, gas-control and electronic components, always specify any mandatory manufacturer or supply-condition requirements when sending your enquiry.
Worldwide Supply of Wärtsilä 6L25DF Spare Parts
Alfa Marine Spare Parts supports international customers requiring Wärtsilä 6L25DF engine parts and spares for scheduled maintenance, urgent repairs and complete overhaul projects.
We assist requirements from shipowners, vessel managers, marine engineers, shipyards, marine repair companies, offshore operators, power-generation operators and commercial vessel operators.
For urgent requirements, provide the delivery destination and required delivery date together with your engine and part information.
Request Wärtsilä 6L25DF Engine Parts
Looking for Wärtsilä 6L25DF engine parts, dual-fuel components, maintenance spares or overhaul parts?
Send us your:
Engine model: Wärtsilä 6L25DF
Engine serial number:
Part number:
Part description:
Quantity:
Required condition: Genuine / OEM / Replacement
Delivery destination:
For larger requirements, send your complete spare-parts list, BOM or overhaul requirement for review.