For frequently asked questions on Yanmar products and services, please select a topic below.



Industrial Engines

Marine Engines

  • OK, I am sold on repowering with Yanmar diesel engines. Where do I start?

    Contact the nearest Yanmar Dealer or Distributor and begin the project. Be prepared to give them complete information on your boat, old engine information, shaft size, prop size, cruise speed and top speed. They will begin a plan of the project and let you know what to expect during the process.

    If you have a question that was not covered in this FAQ section, your local Yanmar Dealer or Distributor can help answer it and explain the features and benefits of powering with Yanmar diesels.

  • I have old gasoline engines in my boat that need to be replaced. I love my boat and don’t mind investing some money as I plan to keep it for several years. What are the advantages of powering with diesel vs. gasoline?

    There are several advantages to powering with diesels. The diesels are generally heavier duty, more reliable, give better fuel economy, give a faster cruise speed, have a longer cruise range, and insurance is often less.

  • What type of oil or coolant do I put in the engine/gear? How much oil do I put in?

    Please refer to the Operation Manual which was written specifically for your engine model. If you do not have the Operation Manual, contact the nearest Yanmar Dealer or Distributor and request one. The manual will specify the type of oil and coolant to use and the intervals to change them.

  • What is the definition of a LDC (Light Duty Commercial) application?

    Any engine used in a revenue producing, government service or rental use is considered a non-recreational craft application and is not covered by the Yanmar Recreational Limited Warranty policy. Rental use is defined as a vessel used for pleasure charter, typically sailboats, sailing catamarans, power catamarans and trawlers. For an engine to be considered for a Light Duty Commercial application it must fall within the following guidelines:

    • Engine is operated at maximum output for less than 5% of total operation hours.
    • Standard operation is at less than 90% of the maximum output RPM.
    • Wide open throttle RPM’s, under load, must reach rated speed in any operating condition.

  • Can I install a Yanmar engine myself?

    Yanmar requires the selling dealer to be responsible for the installation. This might range from performing the entire installation, to a more limited role in one. But the dealer is required to make the final inspection and performance test to assure the engine has been installed to Yanmar’s standards and specifications.

  • What Yanmar engine will replace my old (X) engine?

    Yanmar has a replacement engine for just about anything built in the 25ft. to 50ft. range of boat. The Yanmar regional Distributors are the experts in repowering as they have performed (or have given technical support to) literally thousands of repowers on just about every boat you can name. We suggest that you contact the regional Distributor nearest to you to discuss your project. They can help explain the details up-front so you have no hidden surprises. The Distributor can also recommend a qualified dealer near you who can perform the repower, or assist you in your project.

  • I have an older boat that I love, but the original engines are getting tired. I am thinking about repowering and have heard that Yanmar is a good choice. Why is that?

    Independent research has shown that Yanmar is number one choice for repowering. That is because of the compact size, high power-to-weight ratio, smooth and quiet operation, and legendary reliability.

  • Can I buy an engine direct from Yanmar?

    No, Yanmar sells to regional distributors who stock, customize, sell to dealers, and assist dealers with parts, service, warranty, and technical support.