The new 2.5 hp and 5 hp outboards from Lehr run on the same fuel your barbecue does. Not charcoal, but propane. You can hook up one to the same propane tank you have on the grill, or you can pop in a 16.4-ounce Coleman-style cylinder. We had the exclusive opportunity to run these four-stroke outboards in Marina del Rey, California, near the company’s Los Angeles headquarters. While the horsepower ratings are slight, the prospect of marine engines running on propane — also known as LPG (liquified petroleum gas) — is intriguing. LPG is gaseous at room temperature, so there is no need for a carburetor or other system to vaporize a liquid fuel such as gasoline. It also eliminates the need to prime or choke the engine. A patented fuel metering system delivers propane at a regulated pressure to the combustion chamber. Because the fuel vaporizes on its own, it is impossible to flood the engine or foul the spark plugs.

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