6HA2 Series 278 – 405mhp

Commercial Engines

Yanmar 6HA2 Series Marine Diesel Engine

Powerful and friendly to people and environment.

  • Fuel Economy & Low Emission (meets IMO Tier 2 Compliant)
  • Operational Efficiency (High Torque)
  • Toughness
  • Safety and Easy Maintenance
  • High capacity front PTO which makes various applications possible, for your professional activities on the sea

Engine model

  • 6HA2M-WHT  H Rating  278mhp @ 1880rpm
  • 6HA2M-WHT  M Rating  350mhp @ 1950rpm
  • 6HA2M-WDT  M Rating   405mhp @ 1950rpm


Good Fuel Economy together with Lower Emission

The micro-sized multiple holes in the all-new injectors produce an even finer fuel-oil mist and, combined with new perfectly matched combustion chambers and new cylinder head shapes, produce even more power. It is power delivered smoothly, due to optimum combustion conditions being maintained across a far wider operating range.

High Torque

Excellent Torque – Rise Characteristics in High Speed and High Load Range Enable Stable Performance of Job Duties even at High Load


  • Stable cruising with least speed reduction against sudden load changes
  • A wide range [propeller matching, from passenger ship(light/medium duty) to tug boat(heavy duty), is possible
  • Economical with wide min.fuel consumption range both during cruising or performing job duties
  • Produces stable engine performance even doing other job duties


  • Type Approved by Class Societies
  • Low, stable LOC(Lubricating Oil Consumption) and long overhaul interval.
  • Tufftride treatment cylinder liner and nitrided stainless steel rings and the finely judged clearance between piston and liner.
  • Special treatment injection nozzle

Simplified Maintenance – Low Downtime

Large inspection windows on the side of the block allow in-site replacement of pistions.  Lube Oil filter is easy-to-replace cartridge type.  Full mechanical engine management avoids the chance of delicate and expensive electronics failing in hot, marine engine room conditions.  Maintenance is simplified, inspection and replacement costs are lower.  Reliablity and durability are enhanced.  Engine is user-friendly.

High capacity front PTO

Flexible + Easily adapted for unique + system Hi horsepower P.T.O requirement.

YANMAR Original Marine Gear

Easier Maintenance

The 3-part structure of the case enables the forward shaft and reverse shaft to be disassembled and reassembled while still installed on the boat.  In addition, a cartridge system is now used for the L.O.filter.

Large Capacity & Long Service Life

A fiber friction plate delivered improved trolling performance and increased clutch capacity, in addition, a finer LO filter extends the service life of the bearings and moving parts.

Damping of Fluctuating Torque

High-performance coupling reduces the fluctuating torque that is input to the marine gear.  They reduce rattling and prevent torsional vibration to protect the power transmission parts.