Choosing The Engine for a Yacht

Choosing The Engine

As noted in the introduction to the following excerpt from the John Deere publication Marine Power Source, Vol. 1, 2004,
"John Deere engines are at the heart of many new yacht designs created by Michael Kasten."
The article appears here courtesy of John Deere, and continues as follows:

The Centerpiece of Design

Boat First... or Engine First...?

One way to maximize the efficiency of a marine engine is to design a boat around it. And that’s the exact design approach taken by yacht architect Michael Kasten.

“Rather than slipping an engine into an existing design, we try to create a design that will optimize a particular engine,” explains Kasten. “I can’t design an engine, but I do design boats."

"Once a customer approaches me with their design preferences and general criteria, one of the first things we do is choose an engine and refine the design from there. In other words, I design the boat around the capabilities of the chosen engine. That gives me the freedom to create the best solution for them. It’s a good design approach because you don’t have to settle for an engine that is less than perfectly matched for the vessel.”

Kasten’s preferred engine? “If the boat is big enough for 60 to 70 horsepower, then John Deere is my first choice,” relates Kasten. “That’s my favorite engine for most of my designs, especially trawler yachts.”

The John Deere 4045DFM marine engine is the heart of Kasten’s 40-foot (12 m) Coaster design, an aluminum trawler designed primarily for blue-water cruising. So far, three have been built, one of which is the Good Tern, built by Surrey, B.C., boat builder Wayne Reyse. Producing 85-hp (63 kW) continuous power at 2,500 rpm, the John Deere engine is mated to a Twin Disc gear using a 3:1 reduction to drive a 26-inch (66 cm) fixed propeller, mounted to a 2-inch (5 cm), stainless shaft.

The second 40-foot (12 m) Coaster variant is the Cygnus built by A.F. Theriault of Nova Scotia.

On this vessel, the John Deere engine powers a Sabb controllable-pitch propeller, which Kasten says makes the most efficient use of the John Deere engine’s wide range of horsepower.

“A correctly sized controllable pitch propeller can be efficient at a wide rpm range, since pitch can be adjusted to absorb a large percentage of the power that the engine is capable of producing at nearly any rpm,” explains Kasten.

As a result, the controllable pitch propeller is able to make the most efficient use of the John Deere engine’s strong power and torque curves, Kasten says.

Perfect for cruisers. He adds that John Deere engines are a good choice for those who want a globally supported, durable product at a competitive price — intrinsic genuine value that customers, for generations, have come to know and appreciate in John Deere products.

Kasten recalls early childhood memories of John Deere equipment in rural New Jersey, and that fondness for John Deere has since carried over from land to sea. “All summer we would hear the thump of two cylinders plowing and harvesting the fields,” recalls Kasten, “I like it; it’s a sound forever burned in my psyche.”

Thanks to the modern technology of today’s John Deere marine engines, Kasten and his design clients will have a power source that is smooth and quiet.

Engine: John Deere PowerTech 4045DFM, an 85-hp (63 kW), four cylinder, 4.5L, naturally aspirated diesel engine.

40' Motor Yacht - COASTER by Kasten Marine Design, Inc.

The Original 40' Coaster - Launch Day

All Web Site Graphics, Layout, and Written Content at this Domain Created by Michael Kasten.
All Content Registered with US Library of Congress and US Copyright Office.