John Deere Power Systems added a new engine rating to its current line of marine engine products. The PowerTech 6068SFM has an M5 rating with 300 hp (224 kW) at 2,600 rpm and is for rescue boats, pilot boats, patrol craft, high-speed law enforcement boats, recreational craft and other light-duty applications. This new heat exchanger cooled engine incorporates a seawater aftercooler, electronically controlled fuel system, cruise-by-wire control, diagnostic messaging and self-protection.
"The new John Deere 6068SFM is an ideal powersource for patrol craft because of the compact size and combination of high torque and high power," says Joby Javellana, product market manager for John Deere Power Systems.
"The 6.8L 300 hp marine diesel engine features a power density of 4.5lb./hp, self protection and improved diagnostics, which enables law enforcement officials to complete a mission without an engine failure."
The U.S. government's increased emphasis on homeland security has boosted the demand for patrol boats along its shores, according to Javellana. "Foreign governments have been using our line of marine engines to power their fleet of patrol and law-enforcement vessels, and now, we expect to see a higher level of interest from within our own country," says Javellana.
The 6068SFM is the first John Deere marine engine with an M5 rating - the highest intermittent power rating for propulsion applications, including: traditional propeller shafts, stern drive, jet propulsion and surface drive. The M5 rating defines engines used for propulsion applications that utilize full power no more than one-half hour for each six hours of operation.
These applications typically operate at full power up to eight percent of the time or less and accumulate as many as 300 hours per year.
The high-torque 6068SFM achieves constant power at a rated speed from 2,600 rpm down to 2,300 rpm.
Equipped with seawater aftercooling and a new electronic injection system, the 6.8L marine engine achieves an increase of 75 hp (56 kW) from the 225 hp (168 kW) 6068TFM through increased air and fuel flow.
This PowerTech 6.8L marine engine features a full-authority electronic engine control unit and electronically controlled fuel injection pump, providing excellent fuel economy and throttle response, and protection by self-diagnosis.
"The electronic control unit in the new 6.8L eliminates white smoke generated by the engine," says Javellana.
Equipped with rugged components, the 6068SFM features a heavy-duty crankshaft, larger bearings and stronger connecting rods than competitive marine engines in this class. The heat exchanger, expansion tank and exhaust manifold are integrated into one component, eliminating hoses and fittings that can leak or break.
The new 6.8L offers improved application flexibility including either-side service for twin propulsion applications and poly-V belt drives for increased capacity with reduced maintenance.
The new 6068SFM is tuned for minimum smoke during the acceleration cycle and complies with 2004 EPA and IMO Marpol marine emission standards.