Heavy-duty diesel engines built in the early 20th century to power industrial machinery and workboats are fascinating objects that showcase the complexity and precision of internal combustion technology. Many components inaccessible or invisible on modern engines are over-sized and mounted on the exterior of these antique heavy-duties, making them excellent tools for educating people about how engines work and are maintained. Heavy-duties were also designed to be far more serviceable than modern engines, allowing knowledgeable mechanics to disassemble, repair, and reassemble systems within them using ordinary tools and equipment.
When Rudolph Diesel‘s American patents expired in 1916, American engine manufacturers scrambled to adapt his ideas into hard-working machines to power industry as the coal and oil-fired steam engines of the 1800s aged and were scrapped. The Atlas-Imperial Company of Oakland, the Washington Iron Works of Seattle, the Enterprise Foundry Company, the Fairbanks-Morse & Company of Beloit, the Kahlenberg Shop in Two Rivers, and other companies produced their own lines of heavy-duty diesel engines that became known for their reliability, power, and elegance of design. These engines were installed in tugboats, fish boats, research boats, yachts, and ferries. They also powered logging camps, mining operations, electric companies, municipal utilities, and other on-land operations.
Manufacture and use of these heavy-duties continued well beyond World War II. In the 1950s, however, technological and social changes shifted demand to the newer high-speed diesel and gasoline engines. Companies chose to purchase engines that required less employee labor, at the expense of needing more factory repairs, while labor unions and seaman’s organizations changed engine rooms forever. Even after the heavy-duty assembly lines closed, the engines continued to provide reliable power for decades.
Today, few heavy-duty diesel engines remain in the world and even fewer still operate. As technological innovations in the propulsion field increased, older engines were scrapped or relegated to storage lots where they rusted away in the rain. Modern marine engines have become smaller and more efficient, but far noisier and less interesting than the reliable old heavy-duties.
Fortunately, the few remaining heavy-duty diesel engines are becoming priceless artifacts, accessioned into museum collections and donated to non-profit preservation groups. Others continue to work in tugboats and historic vessels, providing reliable and efficient propulsion as they were designed to more than 70 years ago. These engines provide both a tangible record of past technology and a modern illustration of human ingenuity.