Wärtsilä 34DF

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Wärtsilä 34DF dual fuel marine engine

Advanced dual-fuel technology & efficiency, used for both main engine and generating set applications

The Wärtsilä 34DF is manufactured in configurations from 6L to 16V, giving 500 kW per cylinder and a total maximum mechanical output of 8000 kW. The engine speed is 750 rpm.

Based on the well-proven and reliable Wärtsilä 32 diesel engine introduced in the mid-1990s, fuel flexibility means the engine can be optimized for constant speed generating sets, as well as variable speed mechanical drives, for main engine applications.

Key benefits

  • Flexibility to operate on natural gas and liquid fuels (LFO and HFO)
  • High efficiency
  • Low emissions, due to clean fuel and lean burn combustion
  • Low gas pressure
  • Pilot fuel for ignition of gas
  • Operation in arctic conditions
  • Advanced control.
  • Gas mode operation, 0-100%

Fuel flexibility

The Wärtsilä dual fuel engine capability enables ships to be operated on either conventional liquid marine fuels (LFO, HFO or liquid bio fuel) or LNG. The switch between fuels can be made seamlessly without loss of power or speed. Such fuel flexibility enables compliance with emission regulations in controlled areas, while giving operators the option of determining the fuel according to cost and availability.

When operating in gas mode, the Wärtsilä 34DF engine is already compliant with IMO Tier III regulations without any secondary exhaust gas purification systems. Also, when fuelled by gas, the SOx and CO2 emissions are notably reduced and smokeless operation is attained.

In liquid fuel oil mode, the Wärtsilä dual fuel engines are fully compliant with the IMO Tier II exhaust emissions regulations set out in Annex VI of the MARPOL 73/78 convention. The engine is able to operate efficiently and economically on low sulphur fuels (<0.1% S), making it suitable for operation in emission-controlled areas.

The Wärtsilä 34DF has also obtained certification of emission standard compliance from the United States Environmental Protection Agency (EPA), which further endorses the environmental compliance of this engine.


The Wärtsilä 34DF is the ideal choice for main power source in a vast range of applications, for instance offshore support vessels and platforms, small LNG carriers, ferries & tugs.

Besides serving as mechanical-drive or diesel/gas-electric main engine, the Wärtsilä 34DF is also a perfect fit as auxiliary generating set installed alongside Wärtsilä 46DF or 50DF main propulsion machinery. Thus completing the multi-fuel engine room concept.

Wärtsilä Methane Number Calculator

Wärtsilä 34DF Product guide and 3D models and drawings

Get technical data and system proposals for designing W34DF marine engine installations.


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Article and webinar

A cleaner, greener machine – Wärtsilä W34DF control software upgrade cuts greenhouse gas emissions at all load points
31 AUG 2021 Article
3 min read

A cleaner, greener machine – Wärtsilä 34DF control software upgrade cuts greenhouse gas emissions

Wärtsilä’s new control software upgrade for its...
22 JUN 2021 Webinar

Fueling the future: Delivering fuel efficiency and cutting greenhouse gas emissions through methane slip reduction

Greenhouse gas reduction and fuel...

Press releases

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