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Cummins MerCruiser Diesel Jetdrive

Whatís unique about this new creation is its high volume, axial flow pump that lends thrust very nearly on par with a comparable stern drive. Acceleration comes on strong.

Even more salient than heightened efficiency is CMD's space-savings breakthrough. Gearbox and jet housing have been combined into a single, compact component. The only question I have is why didnít someone think of that before? The elegantless-is-more design shortens length overall by a full two feet. That feature pays big dividends in usable space on board. Just as important: no clumsy jackshaft is required.

Why might you consider a jet drive? With minimal draft and no exposed propeller blades,jet drives are invaluable for shallow water operations where rocks and other submerged debris are a hazard. Swimmers also feel more comfortable in the water. Should CMDís new pump ever foul, simply flip open the top inspection port and clear away the accumulated trash.

Just like a conventional stern drive, a single lever operates both throttle and shift. For easier handling and emergency braking thereís a hydraulic reverse bucket, that when deployed, interrupts the flow of water. Itís just like the thrust reverser on a jet plane. Another nice touch is the integral power takeoff (PTO) typically used to power hydraulic pumps and an electrical generator. Engine riggers will appreciate the way the PTO is positioned on the rear of the gearbox with pump mounting holes both port and starboard.

Suitable for single engine boats up to about 26-feet and for twin engine applications up to about 36 feet, CMD will initially offer its new jet drive powered by a 120-horsepower diesel. But by the end of the year look for the lineup to include models rated up to 250-hp.