MAN Engines launches 30 L V12 marine engine

The MAN D3872 has a new common rail injection system with an injection pressure of 2,200 bar that enables low fuel consumption and optimal raw emissions. (Photo: MAN Engines)

MAN Engines is expanding its engine portfolio for workboats with the MAN D3872 engine series. The newly developed V12 engine has a 30 L displacement – a first for the company – and is suited for medium- and heavy-duty applications.

The D3872 is based on a completely new basic engine that the company said benefits from the findings of the established MAN D2862 V12 engine series. Significant changes include an increase in the wall thicknesses of the crankcase, optimized bolting and a new crankshaft with larger bearing diameters.

The diesel engine’s design was also based on findings from development of the E3872 stationary gas engine, which relies on a large number of common parts in the basic engine. The biogas and natural gas variants of the E3872 have already successfully completed several field trials, MAN Engines said, and entered series production in November 2023.

The MAN D3872 engine series is based on a completely new basic engine. (Photo: MAN Engines)

The D3872 incorporates a new coolant pump and an optimized thermostat housing that provide an improved coolant supply and longer engine life. Optional outer skin cooling is available in place of the closed cooling circuit. The new cylinder head of the engine is aerodynamic and cooling-optimized, the company stated. Improvements have also been made to the oil supply.

A new common rail injection system with an injection pressure of 2,200 bar enables low fuel consumption and optimal raw emissions. Combined with the exhaust gas aftertreatment system, the adapted engine control unit meets current emissions requirements, including EPA Tier 4, IMO Tier III or IMO Tier II. The D3872 can also be combined with the “MAN Smart HYBRID Experience” hybrid system, plus is approved for use with HVO.

The compact installation dimensions of the engine (2,235 x 1,250 x 1,320 mm) are almost identical to those of the MAN V12 series with 24 L displacement. At a 2,720-kg (dry) weight, the engine has a power-to-weight ratio of 2.24 kg per kW (1.65 kg per hp) in a small footprint. In future, it will enable use in combination with a modular exhaust gas aftertreatment system to accommodate confined spaces while complying with the EU Stage V emissions directive.

Source: MAN Engines

The engine is currently undergoing field trials on the water in customer applications with classified engines – for example, in a remotorization project of a passenger ferry. The D3872 LE432 variant with two-stage turbocharging and an output of 1,650 hp (1,213 kW) for medium-duty applications is scheduled to be available at the end of 2024; further power gradations with single-stage charging for heavy-duty applications and aggregates are planned.