When Detroit Diesel and MTU joined forces, great things were expected. The result, however - the Series 2000 engines - exceeds expectations.

THE MARRIAGE of Detroit Diesel and MTU has finally borne fruit - and what a wonderkind it is! The new Series 2000 engines combine successful technologies from both American and German engineering skills. The Mercedes-Benz truck engine blocks, which will be cast in Germany, would have been impossible to build with the metallurgical technologies available just five years ago, according to Ed Crawford, the chief engineer on the project. Major assembly will be U.S.-based, and Detroit is insisting on performing all maintenance on the engines (oil changes, fuel, lube and air filter changes, etc.) for the first two years of ownership, regardless of hours. Detroit also wants to discourage aftermarket modifications by requiring all customizations to be factory-installed options.

Series 2000 engines will be available in 8-V, 12-V and 16-V configurations, with pleasurecraft ratings from 900 co 1,800 horsepower. Interestingly, each of the blocks has its own design. The 12-V isn't simply an 8-V with four more cylinders. Space, weight and performance dictated unit casting rather than modular assembly. The use of dual waste-gated, high-volume turbochargers improves acceleration and virtually eliminates black smoke. The new twist is that during low-speed operation all exhaust pressure is channeled to one turbocharger (sequential turbocharging). This delivers more air pressure at lower rpm because the exhaust pressure must overcome the inertia of only one turbocharger instead of two.

Unburned fuel goes to the fuel-delivery pump, rather than back to the main tank, and is cooled before returning to the injection system. Detroit's two-cycle unit injectors have been replaced with split (two-part) unit injectors. The camshaft-driven, electronically controlled, high-pressure-generating plunger section is located in the well of the "V". High-pressure fuel is channeled to direct-injection nozzles in each cylinder head.

TIGHTER AND COOLER

Individual heads seal the extremely high cylinder pressures that afford more efficient fuel combustion. The intake and exhaust valves in each cylinder are milled in a slightly rotated configuration to take advantage of swirl effects for more complete air intake and exhaust transport.

The main cooling system consists of a series of interlocking titanium places that are lighter, more efficient, provide excellent corrosion resistance, and are easier to clean than tube-and-core bundles. This system first appeared on Deutz, MAN and MTU engines and is also being used on some engines by Caterpillar. The cooling system's split-circuit design creates several distinct segments. Controlling the mixing of hot and cold coolant in these various circuits improves cold-charge air for better combustion, and it eliminates the possibility of overcooling. It also provides excellent overall temperature regulation so that optimum mixes of cold and hot fluids can be maintained at various engine loads.

The 2000's triple-wall exhaust manifolds are cast from a heat-resistant alloy that is encased in an extruded-aluminum outer skin. A dead-air space is left between the manifold and the fluid in the aluminum outer housing, isolating the extreme heat. The results are a cooler manifold outer skin and more efficient heat containment within the manifold itself.

All engine pumps are gear-driven, so only alternator and power take-off belts are needed. This enhances the impressively clean appearance of the engines and should improve overall reliability.

There are a host of other improvements, such as ceramic-surfaced pistons and angled connecting-rod wrist pins, but I think you get the picture. Detroit Diesel's new flagship marine power diesels are truly the engines of the future.

This review/article originally appeared in Motorboating & Yachting Magazine, May 1997 and is written by Jim Daly. For more great yacht reviews, visit their website and subscribe at: https://www.magazinesdirect.com/az-magazines/34207321/motorboat-and-yachting-subscription.thtml?j=QMY