In retrospect, it’s clear that the new Rotax outboard with Stealth Technology, announced Aug. 7 by Bombardier Recreational Products, has been hiding in plain sight since October 2019.
The concept was unveiled as Project Ghost at BRP’s 2019 analysts and investors meeting, along with Project M, which ended up being the Sea-Doo Switch line of jet-powered, compact pontoon boats. The presentation showed BRP boat brands Alumacraft, Manitou and Australia-based Quintrex sporting models with open transoms that had no visible power plants above the swim platforms. Comparison slides showed what those models looked like with Evinrude G2 E-TEC outboards, which would be discontinued seven months later.
Many people, including myself, assumed these images were of boats with jet power or electric motors. What nobody outside the BRP family knew was that the company had already begun work on a gas-powered, propeller-driven, direct-injected, 2-stroke outboard based on Evinrude’s E-TEC G2 technology.
Rotax has created many engines for BRP to power go-karts, side-by-side vehicles, snowmobiles, airplanes, Spyder three-wheelers and Sea-Doo personal watercraft, but Rotax had never made an outboard. The recent design trend of uncluttered sterns has been driven by innovations such as electric motors and jet-propulsed pontoon models, including the Indmar EcoJet showcased on a Sylvan, and BRP’s Switch.
The main problems with these power sources are the electric motor’s lack of range, and the relative inefficiency of jetboat motors. So Rotax resurrected key technologies from the
Evinrude E-TEC G2 outboards. But to tuck it beneath the aft deck, engineers had to change the cylinder orientation from vertical to horizontal. Paul Klug, BRP’s engineering project manager for propulsion, says initial discussions started in April 2019 and involved 17 people from multiple teams who “came up with more than 400 ideas.”
Nuts and Bolts
According to BRP, the benefits of basing the 115-hp and 150-hp Rotax outboards on technology derived from Evinrude’s 1.9-liter, 3-cylinder engine are a 20 percent improvement in fuel economy, a 12 percent reduction in reportable emissions, and a 98 percent reduction in carbon monoxide at idle compared with 4-stroke outboards.
The Rotax outboard is manufactured at the former Evinrude plant in Sturtevant, Wis., where Sea-Doo Switch pontoons are built. “This location gave BRP the opportunity to welcome back many former Evinrude employees to rejoin the company,” Klug says.
Many challenges come with radically changing an outboard’s design and partially submerging it. To keep water out, the cover uses 15 bolts to clamp down on a valve-cover-type seal with a thick bladder. Inner covers help keep noise levels low, and the unit’s location beneath a stern platform creates an additional aural barrier. Air for the combustion chamber is routed through a hose connected to a vent on the transom.
The 150-hp version gets extra horsepower from its RAVE variable-port exhaust system. To get power to the prop from a horizontal crankshaft, a 90-degree gearset was added. “Additionally, our talented engineering team was able to find solutions for water cooling flow and oil distribution,” Klug says.
The engine weighs around 500 pounds, with the first scheduled service at five years or 500 hours.
Manitou Jumps In
Manitou’s 20-, 22- and 24-foot Cruise models, along with its 22-, 24- and 26-foot Explore pontoon models, use the Rotax outboard with the addition of the MAX Deck, which adds 38 square feet of usable space to the stern.
Borrowing technology found in BRP’s Sea-Doo division, which in turn borrowed it from the snowmobile division, the deck comes standard with a 16-inch LinQ attachment kit. It allows owners to connect a host of accessories, such as a 13.5-gallon cooler, to preserve valuable passenger space in the cockpit. Aft-facing Switchback loungers have an unobstructed view of the water.
According to Garrett Koschak, Manitou’s global product manager, a select group of dealers was briefed on the integration of Rotax outboards and invited to give input on price, options and MAX Deck accessories. “In addition, we used qualitative and quantitative research projects to ensure we were capturing the most important customer needs,” Koschak says.
Alumacraft Focuses On Anglers
The addition of the MAX Deck to select Alumacraft Competitor and Trophy models opens up 25 square feet of additional space on the stern. And like the deck on Manitou, the center panel rises when the Rotax outboard is trimmed up for trailering or storage.
The raised deck offers sight-casting anglers a height advantage, and the open space provides room to move about. Alumacraft’s global project manager, Grant Wildgrube, says that because the Rotax outboard is partially submerged, “it also adds a fair amount of buoyancy to the stern of the boat. In addition, our boats have port and starboard 16-inch X-pods on either side of the engine for additional flotation.”
The MAX Deck is also useful in recreation mode. “Anyone who has tried to hold on to an inflated tube when heading out to tow the kids will appreciate the extra space for carrying these large toys,” Wildgrube says. “When certain LinQ accessories are mounted to our Alumatrac system, they can now be moved anywhere on the boat the user has access to the gunwale. The MAX Deck opens up many new opportunities to change how consumers use our boats.”
According to Klug, the first iteration of the Rotax outboard is just the start. “This is only the first wave of what we have set out to achieve in our marine business,” he says. “We plan to continue pushing technology even further. We expect a great response from consumers and look forward to hearing their reaction.”
This article was originally published in the October 2022 issue.