Cummins "K" series marine diesel engines are proving their mettle in a variety of workboat and fishboat applications. According to Cummins, its K engines respond to the market's demand for increased horsepower, better fuel economy, and easier maintenance.
At the top of the K line is the KTA-3076, a turbocharged and aftercooled 16-cylinder diesel that produces 1,250 bhp at 1,800 rpm during continuous-duty operation. The V-16, 3,067-cubic-inch engine weighs just 10,700 pounds, providing a high horsepower-to-weight ratio. Its fuel consumption is rated at 63 gallons per hour. Individual cylinder heads and replaceable wet-type liners help ease service.
The 300-ton towboat Paul A. Wronowski, recently put into service by John A. Wronowski's Thames Shipyard in New London, Conn., is the first vessel powered by the KTA-3076; the 90-foot boat is powered by two of them. Mr. Wronowski points to long years of satisfaction with Cummins engines and service, and says another big reason he chose Cummins is his concern for fuel economy.
The newest towboat to enter the fleet of Brent Towing Company of Greenville, Miss., the Melinda Brent, is powered by twin Cummins KTA-2300 engines. The KTA-2300 produces 940 bhp at 1,800 rpm during continuous duty. The V-12, 2,300-cubic-inch engine is also available in a non-aftercooled model, the KT-2300, rated 700 bhp at 1,800 rpm. Both 2300s feature the same easy maintenance characteristics as the KTA-3067.
Brent Towing is among the first inland waterway operators to take advantage of the K's fuel economy and performance, although the engine has been a favorite of crabber and trawler operators since its introduction in 1979. The 2300 is said to be one of the most fuel-efficient diesels available for its size, with a fuel consumption rating of 47.4 gallons per hour in continuous-duty applications.
The smallest entrant in the Cummins K series is the KTA-1150, a turbocharged and aftercooled, 1,150-cubic-inch, in-line six rated 520 bhp at 1,800 rpm for continuous-duty operation. It has the most economical fuel consumption in its horsepower class, according to published manufacturers' fuel consumption curves. Shippen Marine Inc. of Houston recently put into service the first workboat to be powered by four KTA-1150 engines, the Comet, a 110-foot crew/supply boat.
The KTA-1150 and its non-aftercooled version have also proven popular among fishing fleets, including Singleton Fleets, Inc., a 70-boat shrimping company based in Key West, Fla. Its most recent 15 boats are powered by 1150s. Company president Henry Singleton says he selected Cummins engines because of superior fuel economy and attentive field service.
Cummins Engine Company started manufacturing marine diesel engines in 1921 and has since become a leader in marine diesel technology. In 1932 Cummins introduced the first high-speed marine diesel, and followed up in 1937 with the first supercharged marine diesel. In 1952 the company significantly boosted the horsepower of its marine engines by introducing the first high-speed turbocharged diesel. Cummins engineers tackled the size and dimension problems posed by early marine diesels when they introduced the first "oversquare cylinder" marine diesel in 1961.
Today Cummins offers seven different series of marine diesels for a full range of workboat, fishboat, and pleasure craft applications.