Wärtsilä 34DF – a medium-speed 4-stroke marine engine

Reliable and flexible for constant-speed generating sets in main engine applications, and for variable-speed mechanical drives.

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Reliable power with high fuel efficiency and low emissions

The Wärtsilä 34DF is a medium-speed 4-stroke marine engine that provides reliable and sustainable flexibility to optimise engine operation for both constant-speed generating sets in main engine applications and variable-speed mechanical drives. And with the high power output of the auxiliary generating set you get to maintain fewer cylinders and increase your profit.

The Wärtsilä 34DF is an ideal main engine in configurations from 6L to 16V, giving 500 kW per cylinder and a total maximum mechanical output of 8000 kW. For auxiliary applications, particularly in in-line configuration, the Wärtsilä 34DF genset can deliver up to 520 kW per cylinder at 720 or 750 rpm.

Key benefits of the Wärtsilä 34DF

  • Fully fuel-flexible operation, with ability to run on LNG, HFO or biofuel plus fuel sharing (gas mode operation 0–100%)
  • High efficiency and optimised power output for auxiliary applications
  • High reliability and safety with advanced combustion control and low gas pressure
  • Even lower emissions with an optional greenhouse gas (GHG) reduction package

Why Wärtsilä 34DF?

The Wärtsilä 34DF engine is based on the proven Wärtsilä 32 diesel engine introduced in the mid-90s and it is fully fuel-flexible and capable of running in 100% gas mode. Its dual-fuel capability means you can operate your vessel on LNG or conventional liquid marine fuels such as LFO, HFO or biofuel. Fuel switching happens seamlessly and reliably without loss of power or speed, giving you the option to choose your fuel according to cost
and availability and operate on low-emission fuel when sailing in
emission control areas (ECAs). 

The Wärtsilä 34DF is Tier II compliant in diesel mode and Tier III compliant in gas mode. When integrated with a Wärtsilä NOx Reducer (NOR), Tier III
compliance can also be achieved in diesel mode.

The auxiliary engine also has an optional GHG reduction package available with verified emission levels at factory acceptance tests.

Who is it for?

The Wärtsilä 34DF is a sustainable power source for any vessel operating on LNG. Whether you have a small LNG carrier, an offshore support vessel or a tug, the Wärtsilä 34DF flexibly serves you as a mechanical-drive or diesel/gas-electric main engine. With its outstanding power output and low emission levels it is a perfect solution for your multifuel engine room as an auxiliary generating set installed alongside the main propulsion machinery.

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.

Customer stories
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    The Viking Prince is a Wärtsilä VS 489 Gas PSV design and features excellent energy efficiency, a unique hull form, fuel flexibility, and outstanding vessel performance in areas such as fuel economy and cargo capacity.

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Insights on Wärtsilä 34DF

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