Volvo Penta''s new D9 diesel engine offers very high performance characteristics combined with low exhaust and noise emissions as well as minimal vibrations resulting in a high degree of onboard comfort. Available in two power output alternatives, 500 and 575 horsepower, the Volvo Penta D9 is a powerful alternative for small fishing vessels of about 40 to as much as 50 feet in length. Due to its compact format, the D9 does not occupy much more space than the Volvo Penta 7 litre TAMD75, but it offers almost 100 horsepower more and 30 per cent greater cylinder volume.
The new in-line 6-cylinder marine diesel engine with a cylinder volume of 9.4l has a lot in common with the larger D12 engine. Together with the highly popular 7l TAMD75 engine, Volvo Penta has had the strongest product program for inboard diesel engines in the industry.
The 575-horsepower version has a torque of not less than 1,910 Nm at as low as 1,500 rpms. During the acceleration phase, the D9 is a full 35 per cent better than the TAMD75 .
The high torque is due to the combination of large cylinder volume, electronically controlled unit injectors and, particularly, the completely new turbo. This is a center-mounted, twin-entry turbo that creates the possibility of pulse charging. This means that the power in each exhaust pulse can be used to produce charge pressure, which enables the engine to respond very quickly at low rpms. The charge-air cooling is highly effective and create a low temperature in the intake air, which is an essential prerequisite of the low emission levels.
The turbo is supplemented by electronically controlled unit injectors that at 1,800 bar produce a good fuel-to-air ratio. Four-valve technology also helps ensure the efficient flow of gas.
Electronic control system
The electronic control system of the D9 is called EMS 2 and it was developed by Volvo to meet the coming emission requirements. Faster, more effective electronics make it possible to monitor and control additional engine functions - for example, the engine fuel requirement is analyzed up to 100 times a second. The EMS 2 ensures that the engine always receives the right amount in all operating conditions. The result is a fast response to the driver's commands, low fuel consumption for long cruise range and minimal exhaust emissions.
The low exhaust emissions will meet overall emission requirements that are to be introduced in Europe and the US in 2006.
The electronics also include further improved monitoring. The condition of the piston rings is monitored by the EMS 2 and the level of cooling fluid is also monitored by the system. Engine, controls and instruments are all integrated in Volvo Penta EVC - Electronic Vessel Control - which makes installation simpler and improves operating reliability. EVC, which is based on CAN bus technology, makes it possible to replace all cables usually required for instruments and control with a single serial data cable. Electronic control for shift and throttle is standard.
The D9 has an very powerful engine block that is further strengthened by a fully cast cylinder head and a special ladder frame bolted onto the bottom of the engine block. In-line 6-cylinder configuration that allows room for a well dimensioned crankshaft with large bearing surfaces also helps to produce low vibrations.
The D9 is available with different reverse gears with straight axle and even with V-drive. All versions have electronically controlled gear shift integrated with the engine through the EVC system. Using a low speed slip option, the transmission makes it possible to creep, which is useful for maneuvering into a harbor and in trawling.
