Volvo Penta D8-600: Diesel-Powered Luxury
Modern Diesel Power Propels Luxury at Sea
Volvo Penta’s name and marine-engine history date back more than 100 years to the B1, the first engine produced by Sköfde Gjuteri in 1907. The single-cylinder paraffin (kerosene) engine was given the name Penta, which means “five” in Greek, to commemorate the meeting during which the initial drawings of the powerplant were shown to five men. The Penta was just the beginning. Engine production expanded, leading to the formation of AB Pentaverken in 1919.
Pentaverken’s success continued in the 1920s. During this period, the company began supplying power units for a new automotive manufacturer, Volvo. As the partnership grew, Volvo accumulated an increasing amount of financial interest in the engine builder, assuming full control of the company (eventually renamed AB Volvo Penta) in 1935.
In 1946, Pentaverken introduced its first diesel engine, a smooth, quiet, inline-six. The 1950s brought continued diesel innovation, with the introduction of the world’s first series of turbocharged oil-burners in 1954 and the first charge-air-cooled marine diesel two years later. Around the same time, the world’s smallest direct-injected diesel, the MD1, was introduced. This single-cylinder powerplant featured a revolutionary reverse gear for boats. Through the years, many innovations have improved performance, fuel economy, and reliability of the company’s marine-specific diesels. And that knowledge is showcased in D8-600, the newest engine in the Volvo Penta lineup.
The D8-600 is a 600hp marine diesel I-6 that is lighter and more compact than other engines in its class, giving it one of the best power-to-weight ratios. It is used primarily to power yachts, sport cruisers, and sport-fishing boats. It is designed to be used as a single inboard or in configurations of two or three inboards linked together via Volvo Penta’s Inboard Performance System (IPS). The IPS uses an electronically controlled engine-management system that communicates to Electronic Vessel Control, a centralized operating system for all engines and drive functions.
Being emissions friendly, the D8-600 produces 30 percent less CO2 than previous models, which allows it to meet U.S. EPA Tier 3 and EU RCD Stage II standards. Its electronic common-rail, direct-injection fuel system is designed to reduce emissions, cut down noise, and improve fuel consumption. A reliable geardriven pump provides fuel to the injectors, and a single spin-on filter separates water from the pump. Highlighting the engine is a twin-entry, dual-stage turbocharger (positioned mid-engine), supported by a water-cooled aftercooler that keeps boost temperatures low.
Volvo Penta’s new diesel engine has a one-piece 24-valve cylinder head designed with cross-flow inlets and exhaust ducts for improved air movement, fitted with replaceable valve seats and guides. Using an overhead camshaft makes sure the valves open and close in their proper sequence, requiring fewer moving parts. The cast-aluminum pistons are designed with three piston rings and are cooled by oil that’s stored in an internal galley, helping maintain ideal temperature and lubrication.
A marine-engine’s crankcase needs to be able to put in a hard day’s work and still be dependable. To achieve this level of durability, the D8-600 uses a cast-iron block with a fitted ladder frame to increase strength and rigidity. Replaceable dry liners guarantee coolant doesn’t leak into the cylinders. Moving the pistons is a drop-forged crankshaft that includes induction-hardened bearing surfaces and fillet radii for enhanced strength and durability.
Keeping a marine engine cool is just as important as it is for any other engine, but it has to be done a bit differently due to the engine’s inboard mounting location. A seawater-cooled, tubular heat exchanger is used for the D8-600 to maintain consistent temperature for the closed system’s coolant. Seawater that’s circulated by an impeller pump is also used to cool a tubular oil cooler.
SPECIFICATIONSEngine: Volvo Penta D8-600
Displacement: 7.7L (469.7ci
) Engine Layout: I-6
Valvetrain: SOHC 24-valve
Bore x Stroke: 4.33 x 5.31 inches (110 x 135mm)
Compression Ratio: 16.5:1
Head material: Cast iron
Block material: Cast iron
Piston material: Cast aluminum
Power: 600 hp
Torque: 1,294 lb-ft
Max engine rpm: 3,000
Induction: Twin-entry, dual-stage turbocharger
Exhaust: Cast-iron manifolds
Cooling System: Liquid cooled
Fuel System: Common-rail, direct-injection
Lubrication System: Wet sump
Lubrication Capacity: 7.8 gallons
Dry Weight: 1,852 pounds
Length: 59.1 inches
Width: 38.8 inches
Height: 39.5 inches