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Volvo Penta Engine's New Stern Drives

Single propeller and DuoProp stern drives

Volvo Penta has introduced two new stern drives replacing the current SX and DPS gasoline and diesel stern drives. Even though the model names remain the same, the new drives boast several technological innovations. For example, a reshaped exhaust channel reduces back pressure, significantly speeding acceleration and bumping up horsepower. The drive's two sacrificial anodes can be swapped without hauling the boat. The water intake is cleanable, so floating junk can be easily removed. Curb weight has been cut by 20 pounds. The power trim pump has been integrated into the transom shield, freeing up space in the boat and simplifying installation.

Volvo Penta stern drive housings are traditionally cast in a special marine grade aluminum alloy (low copper content) then coated with a 19-stage surface treatment and multistage painting process. For even more protection there is what Volvo Penta calls its Active Corrosion Protection System, essentially a cathode electrolysis device. It works its magic by measuring the difference in electrical potential and then applying voltage to the water to regulating the difference. Without bogging down in molecular theory, suffice it to say ACPS creates an electrical buffer between corrosion and drive. Pre-drilled holes in the transom shield make ACPS installation or retrofit quick.

Working smarter not harder, Volvo Penta SX single-propeller drive and the DPS Duoprop utilize the same gear case housing and internal components. Individually matched helical cut gears minimize the high-pitched whine commonly associate with whirring gear sets. An oversize rudder surface lends precise steering, especially when maneuvering in tight spaces. The crankcase oil dipstick is located at the top of the motor for easy access. The water pump is mounted on the engine, inside the boat, instead of buried in the water near the gear case. That eliminates the need for costly haul out when the inevitable day comes that the water pump impeller goes south.

The new SX single propeller drive is available with diesels rated 130 and 160 horsepower. Gas motor SX drives are availability with a V-6 or small block V-8. The DPS DuoProp diesels is rated 190 hp. As for gas, the DPS Duoprop comes as either a small block V-8 or a big block V-8s.