All of the engines vibrated at mid-throttle settings, a symptom of their single-cylinder engines. From right to left: the Suzuki, the Mercury, and the Yamaha.

From virtual to reality, that’s where this test took us. Powerboat Reports last covered small 4-stroke engines in a market scan of the 4 to 9.9 horsepower range. This roundup (March 2003) featured 30 different engines and was loaded with data and specifications obtained from dealers and manufacturers. Many of the engines were inspected in dealer showrooms but we did no field testing.

Now it’s time to hit the water with these things. Two of our editors spent a full day with three 4-hp four-strokes. They were lifted, mounted and removed, carried, started, run, checked for features and examined under the hoods. Basically, we got to know them well. …