Volvo Penta D8-450 Specifications
| Engine Model: Volvo Penta D8-450 |
| Engine Type: 4-cycle inline 6-cylinder turbocharged freshwater-cooled diesel |
| Total Displacement: 470 cu.in (7.7 L) |
| Rated Engine Power: 450 Hp (331 kW) at 2,400-2,700 rpm |
| Fuel System Type: Common rail direct injection |
____________________________________________________________________________________
The Volvo Penta D8-450 is an inline-six
cylinder, 7.7-liter diesel engine produced by Volvo Penta, the marine
division of the Volvo Group. This engine belongs to the modern D8
family, introduced to serve both leisure and commercial marine
applications requiring medium-duty power density. The D8-450 utilizes a
twin-entry turbocharger combined with a high-pressure common-rail fuel
injection system, delivering 331 kW (450 hp) at 2,700 rpm.
A freshwater cooling system with a seawater heat exchanger and a charge
air cooler maintains thermal stability under continuous marine load
cycles. The engine integrates fully with Volvo Penta’s Electronic Vessel
Control (EVC) system, providing features including joystick docking,
Glass Cockpit instrumentation, and fuel management functions.
The D8-450 represents a balance between power output and compact
packaging for vessels from 12 to 17 meters (40 to 55 feet) in length.
The bore and stroke dimensions of 110 mm by 135 mm produce a bore/stroke
ratio of 0.81:1, a distinctly undersquare configuration favoring torque
production at reduced engine speeds. Peak torque is generated across a
wide band, with twin-entry turbocharging reducing exhaust gas pulsation
interference to improve low-speed response.
The compression ratio of 16.5:1 enables efficient cold starting and
stable combustion under marine load variations. A cast-iron cylinder
block with a ladder frame construction provides structural rigidity for
the seven main bearing supports, minimizing vibration transmitted to the
hull. The common-rail fuel system operates at pressures up to 1,800 bar,
enabling precise injection timing control for reduced noise and
emissions. Dry weight of 848 kg (1,870 lb) positions this engine
competitively in the 400-500 hp marine diesel segment.
Engine Type: 4-stroke, inline, turbocharged and aftercooled, diesel
Engine Code: D8-450
Configuration: Vertical inline, freshwater-cooled, 6-cylinder
Displacement: 7.70 L (7,700 cc / 470 cu.in)
Bore: 110 mm (4.33 in)
Stroke: 135 mm (5.31 in)
Bore/Stroke Ratio: 0.81:1 (undersquare, long-stroke configuration)
Compression Ratio: 16.5:1-17.0:1 depending on production revision
Firing Order: 1-5-3-6-2-4 (standard inline-six order)
Aspiration: Twin-entry turbocharger with aftercooler (charge air cooler)
Rated Power (crankshaft): 331 kW (450 hp) ±5% at 2,400-2,700 rpm
Rated Power (propeller shaft at gearbox): 324 kW (440 hp) at 2,580-2,700
rpm
Full Throttle Operating Range: 2,400-2,700 rpm
Idle Speed (no load): 650 ± 25 rpm
Peak Torque: 1,750-1,850 Nm (1,290-1,365 lb-ft)
Emissions Compliance: IMO Tier II, EPA Tier 3, RCD Stage II
Rotation (viewed from flywheel end): Counter-clockwise (std)
The cylinder block is constructed from cast iron with a ladder frame
design. A ladder frame is a separate structural girdle bolted across the
main bearing caps, significantly increasing crankcase stiffness and
reducing torsional vibration under continuous high loads. Seven main
bearings support the forged steel crankshaft. Replaceable wet-type
cylinder liners are of the induction-hardened type, allowing service
overhaul without block replacement.
The block incorporates integrated piston cooling jets that direct engine
oil to the underside of each piston crown for thermal management under
turbocharged operation. A rear gear train housing drives the camshaft,
injection pump, water pump, and auxiliary equipment. The deep-skirt
block design extends below the crankshaft centerline for added rigidity.
The cylinder head is a cast iron cross-flow design utilizing a single
overhead camshaft (OHC) with valve actuation via roller rocker arms and
integrated hydraulic lash adjusters. Each cylinder employs four valves:
two intake and two exhaust. This four-valve configuration centralizes
the injector position within the combustion chamber for optimal fuel
spray targeting.
The aftercooler (charge air cooler) mounts directly to the intake
manifold side of the cylinder head. Valve seats are manufactured from a
wear-resistant alloy for extended service intervals in marine
environments. Valve Clearances: Hydraulic lash adjusters provide
automatic zero-clearance operation. No manual adjustment is required
during the engine service life.
The fuel system employs a high-pressure common-rail (HPCR) injection
system manufactured by Delphi or Bosch, depending on production vintage.
A gear-type low-pressure lift pump draws fuel from the tank through a
primary filter with water separator. Fuel passes through a secondary
spin-on filter before reaching the high-pressure fuel pump.
The high-pressure pump generates injection pressures up to 1,800 bar
(26,100 psi), storing pressurized fuel in a common rail accumulator
mounted along the cylinder head. Electronically controlled injectors,
one per cylinder, receive signals from the Engine Control Unit (ECU) to
meter fuel delivery precisely. Each injector provides up to five
injection events per combustion cycle, including pilot, main, and post
injections. The system includes a fuel return circuit that routes excess
fuel and cooling bypass flow back to the tank.
The lubrication system is a pressurized, full-flow filtered system with
a gear-type oil pump. The oil pump is mounted at the front of the
crankshaft. Oil passes through a full-flow spin-on filter mounted on the
cylinder block.
Pressurized oil routes to the seven main bearings, connecting rod
bearings, camshaft bearings, and turbocharger bearings. Piston cooling
jets receive pressurized oil for piston crown cooling. A seawater-cooled
oil cooler, mounted on the engine side, regulates oil temperature using
raw water drawn through the hull.
Total Oil Capacity (including filter and cooler): 27 L (28.5 qt)
Oil Change Volume (with filter replacement): 24-25 L (25.4-26.4 qt)
Recommended Oil: Volvo Penta VDS-4.5 or VDS-5, SAE 15W-40 or 5W-30
Oil Change Interval: 500 hours or 12 months, whichever occurs first
The cooling system is a dual-circuit design combining freshwater (engine
coolant) and seawater (raw water) circuits. A belt-driven centrifugal
water pump circulates freshwater through the cylinder block, cylinder
head, and charge air cooler. A second belt-driven seawater pump draws
raw water through a strainer and hull intake.
Seawater passes through the heat exchanger where it absorbs heat from
the freshwater circuit. After cooling the freshwater, seawater passes
through the oil cooler and finally exits through the exhaust elbow,
mixing with exhaust gases. A thermostat in the freshwater outlet housing
maintains engine temperature.
Freshwater Capacity (engine only): 12-14 L (12.7-14.8 qt).
Total Cooling System Capacity (including heat exchanger and expansion
tank): 27 L (28.5 qt).
Thermostat Opening Temperature: 82-88°C (180-190°F) nominal.
Coolant Type: Ethylene glycol-based anti-freeze meeting Volvo Penta
specification, mixed 40:60 to 50:50 with distilled water.
Charge Air Cooler Type: Seawater-cooled compact unit mounted on the
intake manifold.
Turbocharging System: Twin-entry (divided housing) turbocharger. The
exhaust manifold directs exhaust pulses from cylinders 1-2-3 to one
inlet scroll and cylinders 4-5-6 to the other scroll. This separation
reduces exhaust gas interaction, improving turbine efficiency and
reducing turbocharger lag at low engine speeds.
Aftercooler: Seawater-cooled charge air cooler mounted directly to the
cylinder head intake ports, reducing intake air temperature for
increased air density and combustion efficiency.
Exhaust System: Water-cooled cast iron exhaust manifold with integrated
mixing elbow where seawater injects into exhaust flow.
Electronic Vessel Control (EVC-E3): The engine management system
includes speed control, synchronization for twin installations, remote
diagnostics, vessel monitoring, and third-party control integration via
CAN bus. Joystick driving for IPS-equipped vessels is available.
Electrical System: 12-volt (leisure configuration) or 24-volt
(commercial configuration) with high-output alternator up to 115 A.
Starting System: Electric starter motor, 12V or 24V as per system
voltage.
Air Intake System: Dry-type replaceable element air cleaner with
restriction indicator and flame arrestor for marine safety.
Overall Length: 1,372 mm (54.0 in)-1,531 mm (60.3 in)
Overall Width: 943 mm (37.1 in)-1,027 mm (40.4 in)
Overall Height: 1,143 mm (45.0 in)-1,201 mm (47.3 in)
Dry Weight (engine only): 848 kg (1,870 lb)
Dry Weight (with reverse gear ZF286: 998 kg (2,200 lb)
Engine Oil Capacity (change with filter): 24-25 L (25.4-26.4 qt).
Total Lubrication System Capacity: 27 L (28.5 qt).
Engine Oil Type: Volvo Penta VDS-4.5 or VDS-5, SAE 15W-40.
Freshwater Capacity (engine only): 12-14 L (12.7-14.8 qt).
Coolant Type: Ethylene glycol-based, 40-50% concentration with distilled
water.
Oil Change Interval: 500 hours.
Coolant Change Interval: 2,000 hours or 24 months.
Fuel Filter Replacement: 500 hours.
Impeller Replacement (seawater pump): 500 hours or 12 months.
Valve Clearance Check Interval: First check at 750 hours, then every
1,500 hours.
Valve Clearance (cold): Not adjustable; automatic hydraulic
compensation.
Idle Speed (no load): 650 ± 25 rpm.
Maximum Continuous Operating Angle (list/trim): 15° continuous, 25°
temporary.
Recommended Fuel: Diesel fuel meeting EN 590 or ASTM D975.
Cylinder Head Bolts, Step 1: 60 Nm (44 lb-ft)
Cylinder Head Bolts, Step 2: 120 Nm (89 lb-ft)
Connecting Rod Bolts: 60 Nm (44 lb-ft)
Main Bearing Bolts (ladder frame): 60 Nm (44 lb-ft) lower bolts
Main Bearing Bolts (ladder frame): 100 Nm (74 lb-ft)
Flywheel Bolts: 95 Nm (70 lb-ft)
Crankshaft Pulley Bolt: 400 Nm (295 lb-ft)
Injector Clamp Bolts: 12 Nm (9 lb-ft)
Common Rail Mounting Bolts: 25 Nm (18 lb-ft)
Oil Filter Cap (spin-on cartridge type): 25 Nm (18 lb-ft)
Oil Pan Drain Plug: 35 Nm (26 lb-ft)
Water Pump Mounting Bolts: 25 Nm (18 lb-ft)
Thermostat Housing Bolts: 15 Nm (11 lb-ft)
Turbocharger Mounting Nuts: 40 Nm (30 lb-ft)
Charge Air Cooler Mounting Bolts: 20 Nm (15 lb-ft)
The Volvo Penta D8-450 is installed in the following marine vessel types
and specific applications.
Leisure Vessels: Motor yachts and
flybridge boats from 12-17 m (40-55 ft) including brands such as
Princess Yachts, Fairline, Sunseeker, Prestige, Jeanneau, and Beneteau.
Cruising yachts for semi-displacement and planing hulls.
Commercial Vessels:
Pilot boats and water taxis requiring high reliability and extended
service intervals.
Patrol vessels for law enforcement and customs agencies.
Small passenger ferries and crew transfer vessels for offshore wind
farms.
Harbor tugs and workboats in non-towage roles.
Drive Configurations: Inboard Shaft:
Paired with ZF 286, ZF 285, ZF 325, or HS85 hydraulic marine gearboxes.
Reduction ratios from 1.5:1 to 4.0:1 available. IPS (Inboard Performance
System): Integrated as the Volvo Penta IPS600 (D8 version) with
forward-facing dual propeller pods, providing steerable pod drive with
joystick control.
Generator Drive: Supplied as a
marine auxiliary power unit for vessel generator sets.
Additional Applications:
Re-powering older vessels in the 400-500 hp range with modern
common-rail technology.
Marine rescue vessels (RMV and search-and-rescue configurations).
Dive support vessels and small scientific research platforms.
____________________________________________________________________________________
| Industrial Engines Technical Specifications |
| Car Engines Technical Specifications |
| Small Engines Technical Specifications |
| Outboard Engines Technical Specifications |
