Mitsubishi Heavy Industries Ltd. has announced its production schedule for three new small diesel engines in response to approaching EPA Tier 4 regulations. The new D03CJ, D04CJ and D04EG models provide regulation compliant solutions in the 19kW (25 hp) to 74 kW (99 hp) output range. The Tier 4 compliant D03CJ and D04CJ will begin production in 2013, whereas the Tier 4 interim D04EG is currently available, and the Tier 4 final version will be available in 2015.
D03CJ (1.655L) - three-cylinder design, maximum output of 41kW (55 hp), maximum torque of 165 Nm at 1,800 rpm, power density of 0.24 kW/L
D04CJ (2.207L) - four-cylinder design, maximum output of 55kW (74 hp), maximum torque of 230 Nm at 1,800 rpm, power density of 0.27kW/L
Both engines feature an optimized common rail system with a diesel particulate filter (DPF) and diesel oxidation catalyst (DOC) for Tier 4 compliance. Common MHI goals when developing new engines are to achieve a more compact design without sacrificing power, while also lowering fuel consumption. Appropriately, compared to the previous Tier 3 compliant models being replaced, the D03CJ and D04CJ offer a smaller displacement, while output has been increased. Fuel efficiency is also 16% better than the previous engines.
D04EG (3.331L) - Tier 4 interim, four-cylinder design, maximum output of 74kW (99 hp), maximum torque of 375 Nm at 1,600 rpm, power density of 0.22 kW/L
The engine utilizes a common rail system including an exhaust gas recirculation (EGR) system and a DPF and DOC for Tier 4 interim compliance. Compared with the Tier 3 engine it replaces, the D04EG offers 12% improved fuel economy.
Again, the Tier 4 interim version of the D04EG is currently available, whereas the Tier 4 final model will be available starting in 2015. To achieve Tier 4 final compliance in the power range of 57kW to 74kW, MHI’s current plan is to incorporate a selective catalytic reduction (SCR) system.