TAMD75 is the name of Volvo Penta's latest diesel engine for leisure craft. The TAMD75 is a further development of the TAMD74, which has been a best-seller in its power range for a number of years. Among other features, the new 7-liter engine has an improved injection system and more efficient charged-air cooling, as well as an enhanced EDC system. The result: improved properties, lower fuel consumption, reduced exhaust emissions and better operating characteristics, including less sensitivity to heavier loads and a head sea.
Demand for engines in the 450-500 hp power range has been increasing in recent years. The engines are generally used in dual installations on motorboats about 45 feet in length.
"The international market for sport cruisers and flybridge boats in this power range is very strong and has increased in recent years," Kenneth Norlén, European Sales Manager for Volvo Penta Marine Leisure says. "The predecessor to the TAMD75 EDC has been one of our most successful products. With a new and even better engine, the objective is to further improve boat performance for our customers."
Less sensitive to load
One of Volvo Penta's objectives in developing the new engine was to further adapt the power and torque to conditions that apply to a planing motorboat in the 45-foot class.
"We have worked hard with the power and torque curves so that the engine's power will produce the best possible results in terms of acceleration and speed," says Lennart Sellman, of Volvo Penta's product planning department. "With higher torque from low rpm, you can reach the planing stage quickly."
With the TAMD75, Volvo Penta has broadened the rpm interval in which the engine produces full power, making a boat less sensitive to an increased load and a head sea. When a boat owner takes on additional passengers or cargo, the engine can still produce full power, despite a decrease in rpm's. These are engine properties that are increasingly demanded by customers in the leisure craft field.
Lower fuel consumption and reduced emissions
Many parts of the injection system on the TAMD75 are new. The injection pump works with very high pressure and has a fast injection phase. The nozzles have very small holes, resulting in a thinner fuel mist that burns efficiently. The EDC system has been further developed and the angle of injection has been changed; these factors, together with more efficient charged-air cooling, result in lower fuel consumption. Compared with the previous TAMD74P engine, fuel consumption is five percent lower at cruising speed. Total exhaust emissions have also been reduced.
Refined EDC system
Volvo Penta's electronic EDC engine control system has been further developed for the TAMD75. EDC is a unique system that controls all of the engine's functions, including the transmission. Throttle and change of gear are controlled electronically by easy-to-handle regulators. A built-in diagnostic system monitors the engine continuously; it warns the operator of any faults and can also be used by mechanics when the engine is serviced. Built-in safety functions protect the engine; for example, it is impossible to shift gears at excessively high rpm's. In a dual installation, the engines' rpm's are synchronized, reducing noise and vibration.
EDC also controls the fuel system with extremely high precision. It is largely due to EDC that it is possible to combine high power output with low fuel consumption and low exhaust emissions. Engine power remains constant with fuel temperatures ranging from 5oC to 55oC, which is another important function. Traditional engines lose power when operated in warm climates - but not the TAMD75.
Configuration: Straight-line, 6-cylinder diesel
Cylinder volume: 7.3 liters
Maximum power: 480 hp
Weight, excluding reversing gear 860 kg
July 1, 2002
For additional information, please contact:
AB Volvo Penta
Tel: +46 31 668418