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The Amazing Evolution of Outboard Motors

Evinrude outboard motor factory 1950s
Outboard motors coming off the Evinrude assembly line in the 1950s / Photo- Getty Images

Today's outboard motors are a remarkable piece of engineering.

To tackle the massive history of outboards, I naturally began by searching for the origins of this power system.

To my surprise, I discovered over 117 brands of early outboard motors, whose names are now mostly forgotten. Names like Comet, Anzani, Hurricane, Seagull, Homelite, Thunderbolt, Sea Witch, Water Witch, Sea Horse, Speeditwin, Elto, Motorgo and McCulloch, just to name a few.

Rowing Works, But Only if You Have To

Like most new inventions, outboards were introduced as a result of an opportunity to satisfy a need.

Powerboating during the late 1800s was a sport reserved only for the wealthy. However, manually powered rowboats and canoes were commonly used on small lakes and ponds by nearly everyone. As the need for these craft to travel longer distances increased, ideas for a mechanical means of propulsion began to surface. People wanted a simple small engine that could be attached to the existing boats that they had at the time.

In 1870, Gustave Trouvé was credited with building the first outboard that could be attached to rowboats. It used a small electric motor to drive an eleven pound unit.

The next outboard pioneer of record, Cameron Waterman, in 1883 used a gas engine from his motorcycle to turn a propeller. While he did add a number of improvements to his design, he faced the same concerns as electric car makers face today -- getting a foothold with a new product requires a large supply of development cash. New and better financed players quickly erased his achievements.

Evinrude And His Clever Marketing

One name that stands out among early outboard pioneers is Ole Evinrude. While he had tinkered with motors and outboard designs for several years, but when he opened his new company in 1909 it had two big advantages.

Firstly, Henry Ford had shown him the efficiency of mass production when he started Ford Motors the year prior, so Evinrude also adopted the use of assembly lines. Secondly, his wife, 'Bess' proved to be a gifted marketer. They produced two brand names, Evinrude and Johnson, and sold these motors exclusively to boat dealers and builders. Around the same time, they also produced a motor under the brand name Gale that they sold to hardware, sporting goods, and department stores. The Gale division actually lasted until 1963. This diverse marketing technique used by Evinrude was picked up by other manufacturers. For example, Goodyear Tires stores sold 'Sea Bees,' while Montgomery Ward sold 'Sea Kings' and Eatons sold 'Viking.' Interestingly, most of these secondary brands were also manufactured by Evinrude.

Different Strokes For Different Folks

While many different versions of outboard motors continued to evolve, Asia took a different route in the 1930's. A Taiwainese inventor named Sanong Thitibura clamped a car engine onto a swivel on the transom of a boat, then extended the drive shaft and added a propeller. In essence, he had invented the Longtail outboard. These are still the outboard of choice in Thailand, probably because these long-tails are made economically by using second hand auto and truck engines.

The Post-WWI Boom

Following WWI, the popularity of recreational boating in North America increased dramatically. Dozens of outboard motor companies popped up. The numerous manufacturers resulted in many innovations as well as many new versions. For example, some favoured air cooling while most were built with water cooling. Some outboards had fuel pumps, while others employed pressurized gas tanks. Mercury Outboards was started by Carl Kiekhaefer after he was fired from Evinrude over a design issue. Kiekhaufer followed a similar marketing plan to Evinrude. He established two brand names for his product -- Mercury and Mariner -- thereby permitting twice the number of "exclusive" dealers to be appointed for any given territory. Mercury became the primary competitor to Evinrude throughout much of the 20th century as the industry continued to grow.

But Boaters Wanted More Power

The next big change in outboard history occurred with the introduction of a product that technically competed with the traditional outboard. The inboard/outboard, or "sterndrive" placed the motor inside the boat, but the drive shaft remained outside, as with outboards. The first sterndrive, was designed by the Johnson Motor Company in 1930, but sadly there were few boats at the time that worked well with their system and sales floundered.

950s Johnson Outboard print advertisement
1950s Johnson Outboard print advertisement

In 1948, Charlie Strang, a boat racer and MIT student was looking to set an on-water speed record and drew new plans for a sterndrive system. Years later, a former Mercury engineer, James Wynne, while studying Strang's plans, came up with design changes that made a sterndrive more practical. When Strang and Wynne ended up both working at Mercury, they presented their sterndrive plans to their boss, Carl Kiekhaefer. He rejected the idea.

Shortly after this, Wynne left Mercury, filed a drive patent and sold the design rights to Volvo Penta. Volvo immediately built the new sterndrive, calling it the Volvo Penta “Aquamatic Drive." It was introduced to the world in 1959. The announcement motivated Kiekhaefer to reverse his decision and begin working on an improved version of the Volvo drive system that he called a "MerCruiser." The new drive units could produce up to 140 horsepower. Over the years, different versions of this drive were built and MerCruiser drives are still sold today.

What is important about sterndrive development is that this drive was able to provide higher horsepower to pleasure boaters than they could find with an outboard. This meant that in order for outboard manufacturers to stay in the game, they would have to develop higher horsepower outboards. Several new and qualified manufacturers took up the challenge. Tohatsu offered strong outboards in 1956. Suzuki launched its first outboards in 1965, and Yamaha joined the group in 1984.

New Government Rules

A big surprise was in store for outboard builders in the early 1900s. The US government was about to become a game changer. The Environmental Protection Agency, or EPA, changed emission standards. While four-stroke engines were used in several different applications, two-stroke power was the preferred choice for outboard motors at the time. Two-strokes provided twice the number of power strokes and were less complicated to build than four-strokes.

But the EPA clean air regulations act mandated new technologies for all outboards. The amount of scrambling to meet these regulations differed with each manufacturer. Several had seen the writing on the wall. While Tohatsu had built four-stroke