Marine Commercial - News Release

YANMAR Completes Development of Cleaner, Highly Reliable 6EY26DF Dual-Fuel Engine for Vessels

July 26, 2016
Yanmar Co., Ltd.

YANMAR Co., Ltd. has completed development of a new, reliable dual-fuel engine for vessels that enables the user to switch to and from liquefied natural gas (LNG) and diesel fuel during operation. The new International Maritime Organization (IMO) Tier 3 regulations, introduced in January this year, require an 80% reduction of nitrogen oxides (NOx) emissions from the Tier 1 levels and a 20% improvement of CO2 emissions by 2020. With the flexibility to operate using both LNG, which offers superior environmental benefits, and easy to obtain diesel fuel, the dual-fuel engine has drawn considerable attention in recent years as a solution that easily passes the demanding Tier 3 emissions controls.

 While advanced electronic control is typically required for utilization of two different fuel types, the EY26DF employs high-precision air flow technology that optimizes combustion conditions, delivering stability and reliability when in operation. From here on, YANMAR will continue its efforts towards expanding its dual-fuel engine line-up for vessels, delivering optimal solutions for a wide range of customers.

1. 6EY26DF Engine Features

Fuel Flexibility
-Switch between LNG and diesel fuel mode even under full engine loads
-No power limitations even for LNG

Advanced Engine Control
-Utilizing YANMAR’s innovative technology to control the air-fuel ratio*1 and its knock detection system, the 6EY26DF delivers stability in gas mode.
-Ignition with the micro-pilot injection system, when in gas mode, is as effective as a diesel engine

Cleaner Operation and Greater Thermal Efficiency in Gas Mode
-Compared to the same-class EY26 diesel engine, the 6EY26DF delivers 84% NOx, 25% CO2 and 99% Sox and PM reductions meeting IMO Tier 3 standards
-Gas mode exceeds YANMAR’s current diesel engine thermal efficiency ratios at 46.8%

2. 6EY26DF Specifications
Model: 6EY26DF
Rated power (kW): 1533
Rated speed (min-1): 750
No. of cylinders: 6
Bore x stroke (mm): 260 x 385
Mean effective pressure (MPa): 2.0
Fuel: Heavy fuel oil for vessels, LNG (36.0 to 40.6 MJ/Nm2)

*1: Optimal air flow (air-fuel ratios) for combustion can vary with load fluctuations and methane concentrations. Additionally, as diesel and LNG air and fuel requirements differ, it’s crucial that the engine is equipped with a device for optimizing air-fuel ratios

*2: By injecting minute quantities of diesel fuel, the LNG ignites speeding up combustion


Public Relations Group
Brand Communication Division, Yanmar

  • Note: Information contained in the news release is valid at the time of publication and may differ from the most recently available information.