The MAN B&W L21/31 is a compact, medium-speed, four-stroke inline marine propulsion engine specifically designed for small and medium-sized vessels requiring high reliability, fuel flexibility, and low operational costs. Each cylinder delivers approximately 220 kW, resulting in total power output ranging from 880 kW (4L) to 2,200 kW (10L). The engine produces torque in the range of 12,000 Nm to 30,000 Nm, depending on the number of cylinders and engine speed, providing smooth and efficient propulsion even under varying load conditions. The L21/31 operates on marine diesel oil (MDO) and heavy fuel oil (HFO) and is known for its robustness and simplicity. It meets IMO Tier II emission regulations and can be equipped with a Selective Catalytic Reduction (SCR) system to comply with IMO Tier III for operation in Emission Control Areas (ECAs). Its proven design ensures long service intervals, low fuel consumption, and minimal maintenance requirements, making it ideal for continuous or auxiliary propulsion.

ENGINE SPECIFICATIONS
POWER    MAXIMUM TORQUE    Certification   
2,200 KW    30,000 Nm                  IMO Tier II/III 

NEW GENUINE / REMAN