Well, Suzuki has gone and ruined many boaters’ workout programs, while at the same time making them chillier on cool mornings. Many of us depend on a balky-starting carbureted portable outboard to give us an upper-body workout and warm us up on early-season fishing trips, as we yank on the starter cord with increasing anger for about 50 pulls before we hear the engine reluctantly kick over. But Suzuki has engineered the DF15A and DF20A outboards with electronic fuel injection (EFI), putting an end to our “fun.”
I tested the pair of first-ever carburetor-free outboards in this class at Ocean Reef Club near Key Largo, Fla., on a variety of boats, including a pontoon, a RIB and even a camouflaged duck boat. The one thing they all had in common was that every time I pulled the starter cord, the Suzukis started. No more sweet talking your outboard before the first pull — “C’mon baby, you can do it” — hoping this will be your lucky day. Suzuki made them not only quicker to start but easier as well, with a 20 percent reduced pull. Because the fuel system is pressurized, there’s far less chance that ethanol-laced fuel will clog up the works, which happens frequently on carbureted models. While the new models can survive the effects of E15 fuel, Suzuki recommends using fuel with 10 percent or less ethanol.
Of course, there’s no such thing as a free lunch, and the trade-off is in the weight. An EFI system weighs more than the carburetor, which is about the size of a baby’s fist, but Suzuki somehow managed to make these outboards the lightest in their four-stroke class. The 15-inch-shaft model weighs just 97 pounds, so the DF15A/DF20A is as close to a true portable as you’ll find in this horsepower range, which includes engines such as the 128-pound Mercury 15 Bigfoot.
The outboard aficionado is probably thinking, “Gotcha … an EFI needs a battery to power the electronic fuel injection, right? There goes your weight savings.” Nyet. A magneto generates the necessary starting power after the crankshaft has rotated 720 degrees when the starter cord is pulled, so no battery is needed. Suzuki managed to keep the weight low through a holistic view, making various components slightly lighter while keeping the structural integrity high, something the company has been doing with its racing motorcycles for decades. For example, the all-new fuel injectors are made especially for the DF15A/DF20A and are not pulled from existing larger engines, which would have been a cheaper way to go. Lightweight resins replace certain metals for additional weight savings. Because many parts are smaller, the overall size of the Suzuki makes it the smallest in its class.
In something of a departure from the usual Suzuki premise that “there’s no replacement for displacement,” the 15/20 features a 327 cc engine block, which is slightly smaller than the Yamaha (362 cc) or Honda (362 cc). But during tests, the Suzuki had plenty of zip and outperformed its carbureted brethren by a wide margin. Although horrible weather conditions prevented us from taking the small boats out in the ocean for performance testing, acceleration was impressive in the short area we had in the channel leading out. The 15 hp model had a bit of vibration near idle, but bumping the rpm up a few hundred smoothed it out nicely, and since it is a four-stroke, it was quiet enough to warrant only a passing glance from the egrets and herons in the mangroves.
The two-cylinder engine block is a conventional layout featuring a single overhead cam with two valves per cylinder and a single overhead belt, much like the rest of the four-stroke models in this class. Lubrication is achieved via the wet sump, and it holds 1 liter of oil. Both engines are virtually identical, with the exception of different engine computer mapping, which allows the 20 hp version to have a higher max rpm range (5300-6300) than the 15 hp model (5000-6000). The DF20A also fills the gap between Suzuki’s 15 and 25 hp models, to provide boaters with exactly the right-size engine for their needs. Both can be ordered in manual and electric start.
The trim is among the most versatile in the industry, with five positions and with a shallow-water mode for running across flats or getting into areas not accessible by larger boats. The shallow-water mode can be employed on the fly, so if you suddenly hit skinnier water, you can switch quickly.
Fuel economy is outstanding thanks to the Lean Burn Control System, which Suzuki borrowed from larger models. It reduces the gas/air mixture at mid-range cruising speeds, when the load is reduced, much like what piston-powered aircraft have been doing for decades to save fuel. Both engines have received a three-star rating from the California Air Resources Board (CARB), making them Ultra Low Emission engines. The vast reduction in noxious fumes over a carbureted two-stroke makes the DF15A/DF20A a nice choice as a kicker for back-trolling.
The tiller steering is ergonomically pleasing to the hand with a twist-grip throttle that operates easily. The power band is flat, so you can roll the power on smoothly without a burst of unexpected power when reaching a certain rpm.
The shift lever is at the base of the handle, rather than on the side of the engine like some, which makes it far easier to shift.
Although the MSRP is toward the high end of the 15 hp four-stroke range at $3,329, a quick check of street prices reveals that this model is competitive. Whether you are using your portable as a second motor for trolling, as a backup on your larger boat or for powering your compact pontoon, skiff or tender, Suzuki brings the benefits of EFI performance to the 15 to 20 hp range.