As used in personal watercraft (PWC), the jet ski engine is typically credited to Clayton Jacobson II, an American inventor and entrepreneur. Jacobson is recognized for developing the first commercially successful stand-up personal watercraft, later known as the Jet Ski.

Clayton Jacobson II and the Invention of the Jet Ski Engine…

• Early Development – In the 1960s, Clayton Jacobson II began experimenting with the concept of a personal watercraft that would be fun and easy to operate on the water.
• Prototype – Jacobson’s early prototypes involved modifying existing engines and designing hulls that could be ridden standing up, similar to a motorcycle on water.
• Commercialization – By 1972, Jacobson had refined his designs and launched the first commercially successful stand-up personal watercraft under the brand name “Jet Ski.” This marked the beginning of the modern personal watercraft industry.
• Impact – Jacobson’s invention revolutionized recreational boating, providing a new way for people to enjoy water sports and activities on lakes, rivers, and oceans.

While Jacobson is credited with pioneering the concept and initial commercialization of the jet ski engine, various manufacturers, including Kawasaki, Yamaha, and Bombardier (now BRP), have made subsequent advancements and improvements in engine technology, each contributing to the evolution of personal watercraft engines over the decades.