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6LT Series

6LT Series

500-640 MHP

Experience the power of the 6LT series, offering up to 640 mhp in a compact, high-performance diesel engine. Engineered for fast boats, planing hulls, and light commercial use, it combines advanced technology with unmatched reliability.

6LT models

The 6LT series comes in three different output models.

Clean

Minimal emissions for a greener environment

Interconnective

Seamlessly integrates with smart devices and systems

Quiet

Operates with significantly reduced noise levels

Powerful

Offers up to 640 mhp in a compact size

Fuel efficient

Optimized to consume less fuel per operation

Compact And Powerful

Expanding YANMAR’s renowned common rail range up to an output high of 640 mhp, the 6LT is a compact and light-weight diesel engine. It is an ideal solution for planing and semi-planing hulls, fast boats, with inboard propulsion systems. Ideal for both recreational and light-duty commercial applications.

The powerful 3-model line-up, offering similar benefits to the sister 6LF powerboat series. It adds higher horsepower engines to the YANMAR brand portfolio, creating the largest common rail, electronically-managed marine diesel line-up in the industry.

The 6LT series features YANMAR’s next-generation VC20 vessel control system for enhanced onboard comfort and an easier overall boating experience.

Meeting EPA Tier 3 and EU RCD Stage 2 emissions regulations, the 6LT offers leading fuel economy and also provides a wide range of fuel compatibility to meet requirements for various government service applications.

The 6LT has been customized with YANMAR’s proprietary fuel mapping and a larger mixing elbow for reliable and consistent output performance. It is custom engineered to offer direct connectivity to NMEA and J1939 CAN-bus networks.

Available as a complete package, the engine comes available with a number of standard and optional features. These includes single and 2-pole installation, various ZF gears, and custom secondary alternator options to meet nearly any complex application.

Features

  • Suitable for large superyacht tenders, planing and semi-planing motor yachts up to 55ft, as well as fast boats, and light-duty commercial vessels such as workboats, RIBs, fast rescue boats, and coast guard/military craft
  • High power, low weight, and compact installation creating a high power density of 74 mhp/L liter for the 640 mhp model
  • Controlled by YANMAR VC20 Vessel Control System
  • Complements the largest common rail recreational and light-duty commercial diesel engine line-up on the market
  • Exceeds EPA Tier 3 and EU RCD Stage 2 emissions regulations

Details

  • Available in 3 output models – 500, 580, 640 mhp
  • A proven solution for jet and shaft drives
  • Controlled electronically by YANMAR VC20 Vessel Control System, for 3 engines with up to 4 stations
  • Custom YANMAR fuel mapping and mixing elbow & bracket for reliable performance output
  • Custom YANMAR gearbox configuration to reduce vibration and increase efficiency
  • Custom engine packaging for efficient installation
  • Certified for recreational and light-duty commercial applications*
  • See all certifications details[JR1] 

*Please note, the 6LT640 is not EPA Commercial certified.

Common Rail Technology

As a leading diesel engine manufacturer, YANMAR integrates the most advanced common rail technology into our innovative marine engines.

Common rail technology is a digitally controlled, high-pressure fuel injection and sensor system that optimizes engine efficiency & performance.

FAQ’s about the 6LT series

The 6LT series offers a variety of models with different horsepower ratings to suit various boating needs. It ranges from 500 mph to 640 mph

It’s advisable to discuss your specific requirements with a Yanmar dealer to explore the available options. Consulting with a Yanmar dealer can help determine the best fit.

Please visit our Network Page to find your local distributor or dealer.

Consulting with a Yanmar dealer can help determine the best fit. They can help you determine the best model for your specific needs.

Please visit our Network Page to find your local distributor or dealer.

Maintenance for the 6LT series includes regular servicing as per the schedule outlined in the owner’s manual. Yanmar’s authorized service centers can provide comprehensive maintenance support to keep your engine running smoothly.

Please visit our Network Page to find your local distributor or dealer.

Absolutely, Yanmar’s customer support team and dealer network are available to answer any questions you have about the 6LT series. They can provide detailed information on engine specifications, installation, maintenance, and more.

Please visit our Network Page to find your local distributor or dealer.

Questions and Support

Learn more by searching our FAQs or find your local dealer or distributor from our global network. Please feel free to contact YANMAR Marine with any non-technical questions by visiting our Contact page below.