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The problem with traditional outboards
The blue smoke and racket emitted from an outboard motor form a nostalgic part of many of our memories of life aboard a boat. Ever since Ole Evinrude created the first practical outboard in 1909 and outboards became popular about 80 years ago, the noisy and smelly 2–stroke outboard has been our constant companion. Most outboards hanging on transoms and motor brackets are of the carbureted 2–stroke variety, by far the dominant type, and most of them will still be running for decades. They’re simple, light, powerful for their weight, easy to repair and reliable.
They also blow about 30% of their fuel directly out the exhaust, because the intake and exhaust valves are open at the same time. For every 10 gallons of fuel consumed, about three gallons escapes into the environment. Gasoline is a toxic liquid and contains hundreds of chemical compounds, many known or suspected carcinogens, so keeping gas out of waterways is in everyone’s interest. Since the Environmental Protection Agency has mandated tough new pollution standards, the 2005 model year was the last one for the traditional 2–stroke. If you’re repowering or buying a new dinghy and considering the purchase of an outboard, what are the choices? Fortunately, cleaner outboards with advanced technology are now available.
Gasoline Outboard Alternatives
2–Stroke DFI engines: Much cleaner than old–style 2–stroke engines, lighter but not as efficient as 4–strokes. Reduced oil consumption (by 50%) over conventional 2–stroke engines. They meet EPA 2006 pollution requirements. Currently available in horsepower ratings above about 75hp. We have been shopping for a company powerboat to replace our former vessel, the 26' lobsterboat–style inboard cruiser Showtime, and consider this type an excellent option.
4–Stroke outboards: 4–strokes have been around for about 40 years and are the most popular small–sized gas outboards, with more torque at lower RPM, quiet operation and smoother idling, so they’re great for trolling and make good kicker motors for small sailboats. Cleanest gas–powered motors, and currently available in the entire range of horsepower ratings. The intake and exhaust valves in 4–stroke engines are never open at the same time, so they are efficient gas consumers, unlike dirty and fuel–wasting old–fashioned 2–strokes. 4–strokes run on regular unleaded gasoline, so you don’t need to mix in oil with the gas. The "greenest" alternative in gasoline power.
Electric Outboard Alternatives
Last year the Torqeedo electric outboard appeared and garnered many awards, offering a new alternative to gas engines and traditional trolling motors for powering dinghies and small displacement–hull sail and power craft. Many of our associates have been trying out these German import engines, and we’ll share our perceptions and those of others at the end of this article.
Just a Big Trolling Motor?
Trolling motors have changed very little in about three decades. Simple bow– or stern–mounted electric motors are connected to one, two or three heavy 12V batteries by large copper cables (see West Advisor on Selecting a Trolling Motor in the Fishing Section). Torqeedo introduced an integrated lithium–manganese (LiMa) battery, offering enhanced safety, no awkward battery cables, the highest level of "energy density" and a weight of only about 8lb. Torqeedo breaks new ground with their electronically commutated permanent–magnet excited external rotor "torque" motor, hence the company name. Torqeedos are the only outboards swinging high–efficiency variable–pitch variable–camber propellers. Consequently, their engineering has won a lot of notoriety. Practical Sailor concluded in November, 2007, "Compared to the trolling motors we tested two years ago ("Trolling Motor Test," November 15, 2005) the Torqeedo’s AC motor reflects a big leap in efficiency." See www.torqeedo.com for all of the details about the technology.
Torqeedo Models
Travel 801: The Travel 801 models shown on this page have become a big hit, and most of the comments in this article deal with that engine.
BaseTravel 801: You can save hundreds of dollars if you don’t need a built–in battery or foldable shaft. Base models offer the same drive train but are connected just like conventional trolling motors via cable connections to your boat's existing electrical system of standard lead batteries. Instead of a foldable shaft, they are equipped with a fixed shaft. No lithium batteries are integrated into the BaseTravel models; they are considerably less expensive. A good alternative for longer cruising range with external battery banks (range depends only on the Ah capacity of your batteries). BaseTravel 801 24V long shaft: model 8632762; Base Travel 801 24V short shaft: model 8632770.
Cruise 2.0: The bigger versions are true alternative/hybrid electric propulsion for larger boats, just a step below the Ossa Powerlite system developed by Glacier Bay, which uses a diesel generator to power an electric propulsion system(www.ossapowerlite.com).
Just a Big Trolling Motor?
One of our articulate customers named Jim reported,"Going from a gasoline outboard to a battery powered Torqeedo requires a change in mindset when thinking about range and power. For me, so far, it's a good tradeoff." We have run at full power for about 30 minutes. The twist tiller has five settings: infinitely variable Forward or Reverse, Max. Thrust, Fixed Time of one hour, or Max. Range (about six hours run time) at about 2 knots of speed.
What we Liked
Lightness, simplicity and portability: Customer Tom Ford: "I held the assembled motor in ONE HAND and easily slid onto my floating inflatable to attach it to the transom. Doing this with a small outboard would be a back–breaker with a fair risk of dropping the engine overboard. I installed the battery onto the engine (again with one hand in under 10 seconds) and was off." Like customer Ford, we attach the 17lb. motor without its 8lb. battery pack, which we then carefully place and lock down on the top of the clamped–on motor.
Surprising power: We have used the Torqeedo 801 a lot during the past year on a 20' trailerable sailboat. The outboard buzzes merrily along (a Yachting Monthly reviewer in England reported that it sounds "rather like a sewing machine"). It drives us quietly and cleanly at four or five knots, similar to the speed we have achieved using our 2hp Honda 4–stroke. Another of our customers uses his Torqeedo to motor his classic wood 28' Dragon between a crowded yacht club and a race course. He reports: "Motor and prop seems very efficient, and drives my 3,700 pound keelboat to a maximum speed of just over 4 knots on flat water–not far off the advertised claims."
Tilting the motor down and twisting the tiller handle causes the prop to slowly wind up to maximum thrust. Upon our return to the dock, the LED state–of–charge indicator shows the battery capacity still remaining.
Clean and reliable: What we like best is that the Torqeedo doesn’t make our boat smell like gas, is absolutely safe to use and always starts. It will easily push our boat head–to–wind at a couple knots against a 20–knot breeze while we lower the mainsail.
Areas for Improvement / Overview
Does not have a breakaway shaft kick–up feature if you hit bottom. Battery status LED indicator lights cannot be read in the sunlight. We would like to see a replacement for the phone–jack type connector that clips the wire to the tiller control, and were also a bit doubtful about the number of plastic components used in the product.
However, after a season’s use, we have become enthusiastic fans of the Torqeedo. Practical Sailor’s November 2007 article summarizes the engine’s attributes nicely: "Well cared for, it will serve well on a dinghy whose primary mission is to reach a boat on a mooring. It also makes a great little engine for a daysailor that needs a push into and out of a marina, canal or slip."
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