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Are engine rooms in danger of becoming extinct?

With today’s big outboards, pods and hybrid propulsion, the concept of a traditional engine room is more fluid than the last sip of an hour-old piña colada in the Florida sun. But it hasn’t always been this way. Twenty years ago, almost every motoryacht and convertible over 40 feet was powered by inboard propulsion stuck in a traditional engine room amidships. This fundamentally dictated the layout of much of the rest of the boat. There were rare exceptions, like a custom 50-foot Huckins that had four OMC Sea Drive outboards lashed to the transom back in 1985. At 27 knots, it was fast for a 50-foot pilothouse cruiser in that era. While it was an odd duck 36 years ago, it now seems prescient. Because now more than ever, innovations in propulsion are changing yacht design and even the ways you use your boat.


Traditional inboards locked in the middle of the hull dictate the location of staterooms, salons and every other creature comfort onboard. Sure, designers and builders could sometimes turn those inboards around and couple them to V-drive transmissions. This positions the engines near the transom, but it was about the only trick up our sleeves when it came to apportioning space inside the hull for accommodations—until about 15 years ago.

In 2005, Volvo-Penta introduced IPS pod propulsion which made docking seem like child’s play and allowed diesel-powered boats to have aft engine rooms much like the aging fleet of gas-powered sterndrive express cruisers that had proliferated in the 1980s and ‘90s. Diesel pod propulsion gave birth to a new era of innovation, allowing a 50-foot cruiser to ditch its midship engine room in favor of a full-beam master stateroom plucked out of a larger yacht.

But Volvo-Penta was not the first manufacturer to instigate mechanical vicissitude on board. Fifteen years before IPS, Bayliner offered its Capri runabouts with a Force “L-drive.” This was an effort to install an outboard powerhead inside the hull near the transom and bolt it to a compromised lower unit. A mechanical and sales cluster, the L-drive thankfully lasted only two model years.

Newer attempts to kill the traditional inboard engine room have been more successful. Yamaha’s 350-hp V8 was introduced in 2007. Developed with several production boatbuilders, it allowed for larger center consoles all around. These have all but replaced those sterndrive-powered express cruisers and small convertibles. Twin V8 outboards became the must-have transom accessory right about the time “truck nutz” exploded in popularity all over Florida. I don’t believe in coincidences.

Seven Marine took things a step further and for several years built the world’s most powerful outboards. But that was before none other than Volvo-Penta bought the company and shut it down under the vague auspices of “Science Based Targets,” its excuse to rid the world of 6.2-liter supercharged Cadillac V8 outboards by 2050. Volvo-Penta announced in early 2021 that it was stopping production on big outboards.

The fine folks at Mercury must have nearly choked on their cheese curds when they heard the news. By then, Mercury was busy putting the finishing touches on the most important outboard motor of the century thus far, its 600-hp two-speed automatic V12.

The Mercury V12 in triple, quadruple or quintuple installations will allow yacht designers and builders to develop mighty walk-around sportfishermen and faster cruisers than ever before. The process has already begun with offerings from Viking, Tiara and Formula, but it won’t stop there. And while they’re gasoline engines, their potential to appeal to bluewater boatmen has already been demonstrated by the one-foot-thick order book at the ever-expanding Mercury plant in Fond du Lac, Wisconsin.

Propulsion innovation does not end with IPS pods and outboards. In the superyacht sector, companies like Shottel and Rolls-Royce supply innovative azipods for the world’s largest yachts. Much like IPS, they protrude from the hull bottom. But some of the largest pods don’t even need to be connected to the power source by a shaft. And unlike outboards and truck nutz, they’re hidden from view no matter where the engines are.

Where’s your next engine room going to be? Will you even have one?

This article originally appeared in the September 2021 issue of Power & Motoryacht magazine.