America's Definitive Marine Engine Magazine
Nowadays Rudolf Diesel's German descendants are famous for high-speed marine diesel engines ranging from 550 to 1550 horsepower. For the record, the MAN Group ranks as one of Europe’s leading manufacturers of machinery and vehicles with annual sales of €14 billion.
MAN’s R6-550, is a six-cylinder in-line block rated 550-horsepower, a potent, common rail marine engine appropriate for motoryachts ranging in size from 40 to about 70-feet. What’s particularly appealing is the fact that it boasts such an impressively high weight-to-power ratio along with a compact footprint. That pays big dividends by more effortlessly fitting higher horsepower in a smaller space at the same time fuel consumption is improved. Want numbers? The weight-to-power ratio is 3.60-lbs/hp with an output ratio is 1.31 hp/cubic inch displacement. These good as gold numbers were virtually unheard of only a decade ago.
Der diesel R6-550 gets marching orders from an electronic engine control that’s also integrated with electronic diagnostic and a monitoring system. Dubbed the MAN Monitoring and Diagnostic System, firmware also records general shipping reports and alarms. With MMDS boat captains clearly see vital information on a high resolution TFT display (6.3-, 10- or 15-inch). Monitoring systems record all engine-specific data, things like oil pressure, turbo boost pressure and charge-air temperature and the level and coolant temperature. The system number crunches speed, rpm and fuel flow to post range and real time consumption. For safety sake, MMDS reduces rpm in the unlikely event of perilous operating conditions, which might otherwise put the engine at risk. In other words, it would be hard to hurt this engine by overheating it or running it out of oil.
Thanks to common rail injection MAN’s wild child features crisp acceleration and high speed, combined with smooth, quiet running. No big surprise, the motor complies with international pollutant limits in accordance with EPA tier 2, IMO, and RCD 94/25/EC. Because MAN is a global manufacturer with representation in virtually every country in the world, service is not likely to be a problem no matter how far from homeport you cruise. MAN employs 100 common rail certified technicians through the USA. All authorized service dealers have necessary parts and special tools on hand. Should they not have a particular part, they can special order anything from a gasket to an engine block with 24 hour delivery anywhere in the USA
A final point of interest. MAN requires the use of fully synthetic engine oil (super high performance diesel engine oil) for all its Common Rail engines in operation in North, Central, and South America.