12AYM-WGT (L Rating)
12AY Series

Engine Specifications


Commercial Engine

Power Output (HP)


Power Output (kW)


Rated Speed

1940 RPM





Bore x Stroke

155mm x 180mm


Turbocharged & Intercooled

Dry Weight



2743mm x 1642mm x 1707mm




IMO Tier 2

Series Information

The mammoth 40 litre V12 Yanmar 12AY delivers a new level of performance and efficiency to commercial boating operators. Renowned throughout the world for reliable, durable and efficient marine power plants, the Yanmar 12AY series is suitable for the high-speed commercial workboat diesel market. With easy installation and maintenance, the purpose-built 12AY is ideal for offshore support vessels, passenger ferries, tugs, commercial fishing craft and other demanding applications.


  • Low fuel consumption for economical power
  • High torque characteristic for power when you need it most
  • IMO Tier II emission compliant
  • Stable cruising with least speed reduction against sudden load changes
  • Includes Yanmar’s famous easy maintenance access and long service intervals

V12 power born from years of experience with the latest technology

Since the 12LA and 16LA series engines were first sold in 1980’s, Yanmar has supplied more than 2,500 of them around the world. Based on this success and further research and testing, Yanmar have developed the new 12AY series - a reliable, high-performance V12 engine reborn as our 1,000 hp-plus high-power model. We use the same proven technology from our best-selling 6AY series, meeting IMO Tier ll exhaust emission standards without electronic engine control. With its stable high torque, this engine features a prolonged lifecycle design that boasts low NOx and fuel consumption thanks to a new and efficient combustion method, improved durability, and Yanmar’s famous easy and hassle free maintenance.

* All information shown is to be used as general information only. Images shown are for illustration purposes only and may not represent the final product. All dimensions, power outputs and technical details are approximate and may vary from time to time depending on a range of factors. Any data shown is subject to change without notice. Some items or accessories may not be available in all areas/regions. Please consult your Authorised Dealer or Power Equipment Account Manager for all technical information.

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