Recently, while editing my first industrial newspaper, I talked with truckies who had switched to electronically-managed diesels. The fuel economy of Volvo's EDC (Electronic Diesel Control) is another plus. From flywheel to alternator drive-belt pulley, the 74P EDC is 1142mm long while the overall width is 794mm and height a fairly imposing 937mm. At 860kg in bobtail form (sans gearbox), the 74P EDC is 67% heavier than Yanmar's 6LY2-STE. More so when matched with one of ZF's two speed gearboxes.Ī suitable model is the electronically-controlled ZF IRM 300 ATS, which has a 7° down-angle output flange and weighs 116kg, 69kg less than Volvo's own single speed electronically-operated hydraulic gearbox.Īccording to ZF, overall the best ratios for planing hull application would be the 2.000:1 in first and 1.567:1 in second combination.īuilding a diesel which can handle severe operating conditions does however, increase its weight. The low revs at which maximum torque is developed also makes the motor particularly flexible. These outputs are not bad for a motor that has a piston displacement of 7.28lt. Even at 1000 revs the Volvo develops 730Nm of torque. The long stroke (135mm compared to the 107 bore) powerhead develops maximum torque of 1432Nm at just 1600 revs, 29% more and 900 revs lower than its more compact Japanese rival. The 74P EDC develops a maximum of 480 hp at 2600 revs, 14% more than Yanmar's 6LY2-STE but at 700 fewer revs. This provides plenty of 'grunt' for planing larger gameboats and cruisers. Most truck engines develop maximum power at moderate revs and maximum torque well down in the rev range. There's even an oil dipstick on both sides of the engine for ease of maintenance in marine applications. The fuel system is designed to handle ambient temperatures from 5-55☌ and features six-hole injectors for efficient fuel spray and lower emissions. The 74P EDC is no exception and has lots of good features like replaceable wet cylinder-liners and valve seats/guides, two separate cylinder-heads with a flame barrier between them to protect the head gasket as well as 12V or 24V electrical system with 60 amp alternator. Most heavy truck diesels have features which ensure a long service life and the ability to be overhauled at least a couple of times. There is nothing wrong with using truck diesels in marine applications. Volvo's new low-emission truck-origin diesel slots in neatly between Yanmar's 420 hp 6LY2-STE and the 660 hp Cat 3196 and 635 hp Cummins QSM11. This in summary, is exactly what the new Volvo low-emission TAMD 74P EDC is, a proven terrestrial diesel that's been re-engineered to suit a variety of marine applications. Adding together sophisticated electronic engine management and diesel, while retaining a relatively mechanically simple motor, is one way of meeting strict exhaust emission regulations.

Volvo tamd 73 edc manual