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Cummins Quantum Tech Marine Diesel Engines

Cummins MerCruiser Series of QSD Diesels

Cummins Diesel Quantum Series diesel technology spans three new platforms, including 2.0, 2.8 and 4.2 liter engines, with ratings ranging from 115 to 350 hp.

Cummins MerCruiser Diesel 115 hp marine diesel stern drive

Both four - and six-cylinder configurations of the QSD series are offered for both stern drives and inboards. Here we find sophisticated electronics running the show. True to the Quantum colors, all three of the new motors run on high pressure common rail injection. QSD features high pressure common rail injection with the attendant fuel savings plus significant smoke and noise reduction. You cruise further on a tank of fuel with a more comfortable ride. The CMD Electronic Control Module and MerCruiser SmartCraft combo not only meters fuel and turbocharger boost, and also monitors vital statistics like oil pressure and coolant temperature. Cummins MerCruiser Diesel marine diesel engine assembly line.

A torsional drive shaft coupler lends a smoother ride. Counter balance shafts on the engine also smooth vibration. Heat exchangers and exhaust manifolds have been incorporated into the engine to reduce size and weight. Beyond fuel efficiency and smart engine management, the real eyebrow raiser is the fact that modest dimensions and relatively lightweight make QSD series of diesels a wise and viable replacement for gasoline engines.

Above left the Cummins MerCruiser diesel Quantum Series: The 2.0 Liter marine diesel sterndrive rated 115 hp. Bottom left, the Cummins marine diesel assembly line.

Model Horsepower Displacement Cylinder Configuration Fuel rpm
MerCruiser 1.7 120 1.7 Liter I-4 Electric 4400
MerCruiser 2.8 ES 170 2.8 Liter I-4 Electric 3800
MerCruiser 4.2 MS 200 4.2 Liter I-6 Electric 3600
MerCruiser 4.2 ES 250 4.2 Liter I-6 Electric 3800 to 3900