This new in-line six-cylinder diesel from DDC/Volvo packs a wallop and is coming your way soon.
Slated for introduction at the 1998 Ft. Lauderdale International Boat Show, DDC/Volvo Penta's new 7-liter Series 74 EDC in-line six-cylinder diesel is said to develop 480 crankshaft horsepower at 2600 rpm.
Sitting in the same envelope as the 6.9-liter Series 73 EDC engine which produces 430 horsepower, the new diesel has increased the cylinder volume to 7.3 liters and uses Electronic Diesel Control (EDC) developed by Volvo.
While the size and power of the Series 74 engine has broad appeal for new boats, its 2,304 lb. dry weight with MG 5075 reverse gear also makes it an excellent choice for repowering. A friend of mine with a 36 Tiara powered by heavy V-8 diesels is a prime candidate.
According to DDC/Volvo, the Series 74 engine with 4.12" bore and 5.35" stroke packs 444 cid and a compression ratio of 17.5:1. The diesel is said to develop tremendous torque at low rpm to help get the boat out of the hole and on plane quickly, which should minimize smoke and enhance fuel efficiency. DDC/Volvo expects the engine to burn about 15.5 gallons per hour at a 2200 rpm cruise. At full chat, the Series 74 will likely consume 27 gallons per hour.
Having spent some time on different boats with the Series 73 engine equipped with EDC, I have found the system to offer numerous benefits for both the boatbuilder and the end user. For the boatbuilder, installation moves quickly since conventional control cables are replaced with wiring harnesses for both throttle and clutches. Plug-in components mean there's little if any adjusting to do and allows multi-station installations by simply mounting plug-in junction boxes where needed.
DDC/Volvo's new Series 74 EDC four-cycle diesel develops 480 hp in a slim, trim, in-line six-cylinder package.
I've run many sportfishing boats with standard cable controls in the tuna tower, flying bridge and cockpit. Even when new, these long runs require considerable effort to operate because cables don't take even gentle bends too happily. As cables age and weather in salt and heat, the condition worsens.
Electronic controls, on the other hand, work smoothly and require no more than finger strength to operate.
The EDC system has a processor as its brain. The unit is mounted directly to the engine and is housed in a polyurethanepainted die-cast aluminum box. As the heart of the system, this processor takes information sent to it from sensors located throughout the engine. Powerful enough to assess this data up to 100 times per second, the information is then computed so the fuel pump can deliver the exact quantity of fuel needed for the ambient conditions, such as air and water temperatures, air pressure and propeller load. If you've ever had a mechanical engine stall in close quarters because of an idle that's set too low, or have killed the engine in a panic stop, you'll find that electronics can eliminate these instances.
The best news is you don't need to be a computer whiz to appreciate the lack of white smoke at start-up, the quick throttle response, or lower emissions throughout the engine's range of power. The EDC also can compensate for high fuel temperatures, to prevent power loss during hot, humid weather.
Another important feature of the EDC is the built-in selfdiagnostic tool. This control unit constantly monitors the status of vital engine systems. If the cooling sensor notices a glitch, for example, a blinking light on the dash will alert the operator instantly. By counting the number of blinks, the operator will be able to determine the source of the problem by consulting the code book that comes with the engine. If it's a simple fix like a loose connection, the operator can take care of it in the field. If the problem is more serious, service is as close as a phone.
Two features provided by the control head are especially useful. The first lets you adjust the idle setting with a range from 550 to 750 rpm. That's good news in areas where no-wake zones are common and the factory setting may be too high for easy maneuverability. Likewise, in tight docking situations, being able to adjust the idle will mean better control. A second handy item is the built-in engine synchronizer. Due to its design, the system is active and on all the time with the port engine acting as master and the starboard engine the slave. Press the synch button and each engine acts independently.
While DDC/Volvo plans to introduce the new Series 74 in Ft. Lauderdale, delivery in limited numbers will commence at the end of November. Full production will begin in January 1999.
The 430 hp DDC/Volvo Series 73 EDC will continue in production.
This review/article originally appeared in Yachting Magazine, November 1998 and is written by Peter Frederiksen. For more great powerboat reviews, visit their website and subscribe at: https://www.yachtingmagazine.com/subscribe-to-yachting-magazine/