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Reliable and efficient four-stroke small-bore engines

Regulatory and fuel-related uncertainty can make it difficult to plan investments in propulsion and GenSets. With our small-bore engines, you are prepared for whatever lies ahead.

MAN Energy Solutions has built its position as the leading designer and developer of small-bore engines for the world’s merchant marine fleet on the basis of high reliability and efficiency.

Thanks to the low maintenance requirements, our engines provides extended lifetime, and additionally offer long time between overhauls (TBO). When needed, our service experts are there for you – every day and everywhere around the world.

MAN small-bore engine portfolio for the world’s merchant fleet

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More than
20000
MAN Energy Solutions small-bore engines are in service today
MAN PrimeServ
24
/7
service with passion
across the globe

Key benefits

  • Proven reliabilty

    Our small-bore engines are designed for lifelong operational reliability, availability and minimal downtime – they are ready and up running when you need them. Sturdy engine blocks, stiff crankshafts and robust connecting rods are just some of the basic design characteristics which secure trouble-free operation and long overhaul intervals.

  • High efficiency

    Efficient performance has a measurable effect on both the environment and your bottom line. It also explains why more than 19,000 of our engines are in service worldwide. Our dual-fuel engines let you select the most economic fuel type for the operating conditions. The cost optimized fuel injection system is also designed for high reliability and cost-efficiency.

  • Future-proof solutions

    The main uncertainties affecting engine choice have to do with the environmental and cost factors of fuel. Our answer is flexibility. Our single-fuel engines can run on conventional fuel types and also bio-fuel oils. Dual-fuel engines let you use methane as additional fuel type. The MAN L21/31DF-M and MAN L27/38DF-M can use methanol as second fuel type.  Our retrofitting expertise offers flexibility, now and in the future.

Full range of MAN four-stroke small-bore engines

Explore the capabilities and range of our engines.

GenSets and Diesel-electric propulsion

MAN L28/32DF GenSet

Based on the ultra-reliable and robust MAN 28/32H, the dual-fuel version is available as newbuild or retrofit and adds the ability to run on methane, with its economic and environmental advantages. High efficiency in gas and diesel mode makes it a perfect GenSet as part of a complete power package with four-stroke or two-stroke propulsion engines. Easy operation, easy maintenance and proven reliability also make it a trusted propulsion engine with long times between overhauls and low life cycle costs.

  • 720 – 750 rpm
  • 1,050 – 1,890 kW
  • 1,000 – 1,800 kWe

MAN L23/30H Mk3 GenSet

By applying innovative technology to classic design principles, the MAN L23/30H Mk3 is engineered to meet the power needs of most commercial ship types. Straight forward integration requirements make it a perfect choice for low-cost installation, while well-known maintenance procedures and common spare parts reduce operating costs. The new model raises power output per cylinder by 15-20% and reduces fuel oil consumption.

  • 720 – 900 rpm
  • 500 – 1,800 kW
  • 475 – 1,710 kWe

MAN L23/30DF GenSet

The MAN L23/30DF dual-fuel GenSet lets you select the most economic fuel for the operating condition. The cost optimized fuel injection system is designed for high reliability and cost-efficiency. It uses the main injection valve to inject pilot oil. This way, separate injectors, piping and pumps for main oil and pilot oil or a common rail system are not needed, saving on installation costs and maintenance. The monocoque design also eases the installation of the engine series and reduces weight.

  • 720 – 900 rpm
  • 625 – 1,320 kW
  • 590 – 1,255 kWe

This methanol-fuelled engine is a compact and reliable power source designed to run on methanol, heavy fuel oil (HFO), and most bio-fuel oils. When powered by green methanol, it is carbon neutral. The new engine type maintains the reliability and low consumption of the proven MAN 21/31, ensuring security of power supply on large vessels and handling load steps with confidence.

  • 900 – 1,000 rpm
  • 1,000 – 1,980 kW
  • 950 – 1,880 kWe

This GenSet operates at the lowest possible accumulated costs during their complete life cycle thus providing a safe investment.

A methanol conversion will be available soon as a retrofit for existing MAN 21/31 GenSets.

  • 900 – 1,000 rpm
  • 1,000 – 1,980 kW
  • 950 - 1,880 kWe

Propulsion engines

The robust and reliable MAN L27/38 delivers good performance over the entire load range with quick acceleration and immediate load response. Its proven reliability ensures long time between overhauls (TBO) and no unscheduled maintenance or repair work.

This engine is available as methanol-ready version.

  • 750 – 900 rpm
  • 2,100 – 3,690 kW

MAN L21/31 propulsion

The MAN L21/31 engine combines intelligent use of fuel in marine applications with flexible propulsion systems. It is the ideal power source, for example, for small to medium-sized tankers, cargo ships and ferries.

The proven engine is characterized by its reliability and low consumption. 

This engine is available as methanol-ready version.

  • 1,000 rpm
  • 1,290 – 1,935 kW
36000
h
time between overhaul extensions possible

Plan your vessel with confidence

Get in touch with our four-stroke small-bore experts for in-depth advice on all your propulsion and GenSet questions. Start your change process now and reach out to us today.

Contact our experts

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Related news

Thursday, April 10, 2025

MAN 175D Engines Selected for Carbon Capture Storage Application

GenSets to boost auxiliary systems during CO2 discharge

The Royal Niestern Sander shipyard in the Netherlands has ordered 2 × MAN 16V175D MEM engines (2,400 kWm/1,800 rpm) in connection with the building of an MPV (Multi-Purpose Vessel) vessel – ‘Easymax 5’ – for Dutch outfit, Wagenborg Operator. The engines will be employed as GenSets for power generation aboard the purpose-built CO2 carrier, which will be employed in the offshore, substrate storage of CO2.

The vessel will be the fifth under the EasyMax concept jointly developed by Wagenborg and Niestern Sander with a cargo capacity of 14,000 tons. It will ultimately be chartered by Ineos, Denmark and the 175D engines are scheduled for delivery during 2025.

The CO2 for storage will come from a bio-gas plant in Denmark, from where it will be transported to Esbjerg on the Danish west coast for loading aboard the vessel before proceeding to the Greensand storage site in the Danish North Sea. The MAN 175D GenSets are intended to give the Easymax 5’s CO2 pump and DP2 systems more power during discharge into offshore storage.

Bart Speckens, Regional Sales Manager, MAN Energy Solutions, said: “This order represents a new type of reference for the 175D. In general, 175D is a versatile engine with the lowest environmental footprint and operating costs in its class due to its high fuel-efficiency and long service-intervals. We’re proud to be involved in such a crucial project that ultimately will sequester millions of tonnes of carbon dioxide from hard-to-abate industries.”

In keeping with its slogan of ‘Moving Big Things to Zero’, MAN Energy Solutions provides the shipping industry with green engines that can operate on climate-neutral fuels, but also offers the actual carbon-capture-and-processing technologies essential for global industry to achieve net zero. Once captured, CO2 can be stored and reused to form the backbone of a circular carbon economy. Of the 18 large-scale facilities currently in commercial operation globally, fully eight employ MAN CO2 compression technology.

About the MAN 175D engine

MAN Energy Solutions developed the MAN 175D engine range to supplement and complete its product portfolio in the maritime sector. Available in three variants of 12-, 16- and 20-cylinders, the engine is available with an output ranging from 1,500 to 4,400 Kilowatts and is optimised for propelling ferries, offshore support ships, tugs and other working vessels. Other market areas, such as superyachts, planing yachts and naval marine applications are also served by additional engine variants.

The 175D is also an extremely eco-friendly engine, having been designed from the outset for low fuel consumption, coupled with compliance to the latest exhaust-gas-emission standards and considering as well future-fuel requirements where it is already cleared for operation on biofuels such as FAME and HVO.

Wagenborg has announced a newbuild CO2 carrier vessel based on award-winning EasyMax design

Documents

  • PR Easymaxx 175D_EN
    PDF, 144 KB English

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Contact

Nils Søholt

Trade Press Marine

Group Communications & MarktingMAN Energy SolutionsTeglholmsgade 412450 Copenhagen SVDenmark

t +45 33 85 26 69

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