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Cummins QSB 5.9 liter Marine Diesel

Cummins Marine Diesel QSB5.9

A Common Rail Marine Diesel
That's Easy on the Ears.


Cummin’s Marine QSB 5.9
Cylinder Block Configuration InLine-6
Displacement 5.9 Liters
Bore x Stroke 4.02” x 4.72”
Horsepower 207-470
Aspiration Turbocharged
Weight 1350 pounds

For those unfamiliar with the Cummins Marine's QSB platform, it's populated by a 5.9 Liter powerhouses ranging from 230 to 370 hp. Both recreational and commercial models of marine diesel are offered. The most recent addition is a potent new 425-hp version replete with turbocharger and a 24-valve cylinder head.

Truly a state-of-the-art creation, the Cummins Diesel QSB5.9 features high-pressure, common-rail fuel injection. for those unfamiliar with the technology, it's renowned for the dividends it pays in improved fuel economy, instant starting and particularly low emissions On the aesthetic side of the balance sheet. Smoke and smell are virtually nonexistent. Plus the engine is easy on the ears, with noise levels at idle quieter by about 80 percent.

Predictably, engine operations are electronically controlled, with data communicated to the helm station by way of the Mercury SmartCraft information pathway. Data includes the engine's vital signs (temperatures and pressures), and of course fuel flow. Self diagnostics is also part of the bundle with formation shown on CMD's digital Display View. An optional set of analog gauges speak SmartCraft. Throttle and shift controls are electronic, and the system accommodates either single or dual engines linked to as many as six stations. Engine synchronization is part of the SmartCraft package.

Aficionados will appreciate Cummins Diesel's vertical mounted fuel injectors that are neatly centered over the combustion chambers, lending cleaner combustion and longer life. A special reinforcing skirt stiffens the cylinder block, gripping the crankshaft tightly in its journals. This is a critical feature in a marine engine because with every jolt of a wave, the crankshaft tries to plummet right through the oil pan and out the bottom of the boat.