Volvo 375-hp gas sterndrive
Standard power in the Hunt 25 is the 375-hp Volvo Duoprop sterndrive. It offers excellent handling and the strongest acceleration on plane at just 5 seconds, lagging just a half-second behind the diesel sterndrive to 20 knots. This puts the diesel sterndrive’s strong midrange performance in perspective, beating the gas-powered sterndrive to 20 knots, even if only by a whisker.
There are a number of good reasons for choosing a gas sterndrive over the diesel, including its lower price, higher top speed, and the quietest noise levels, at least at low speed: 65 dBA at 5 knots compared to 68 dBA for the diesel inboard and 70 dBA for the diesel sterndrive. Idling around the dock, the gas engine is also a lot smoother than the diesels, which vibrate more at idle than they do at 1,000-plus rpm. At a 30-knot cruise, though, the diesel inboard was actually quieter — just 84 dBA compared to 86 dBA for both gas and diesel sterndrives — and the gas I/O was loudest of all at full power.
Read the other stories in this package: On Powerboats – Propulsion test: inboard, sterndrive, jet The Sea Trials – Volvo D4 300-hp diesel inboard The Sea Trials – Yanmar 315/Ultrajet The Sea Trials - Volvo D4 300-hp diesel sterndrive
Range and economy don’t compare with the two diesels. While the diesel fumes are barely noticeable, you know you’re on a diesel boat when idling around. If you want to avoid any hint of diesel exhaust, go with the gas engine. While a gas engine won’t last as long as a diesel, for most people it’s academic. Most owners don’t put more than 100 to 200 hours a year on their boats, so the 2,000 hour engine life that you could expect from a gas engine, given reasonable care, equates to many years of service.