The Catalina 22 requires an outboard engine in the 3 to 6 horsepower range should you desire to purchase one. The factory provides an optional outboard bracket or you may purchase a commercial one. “Long shaft engines” are preferable but regular shaft will work satisfactory.
Coast Guard regulations require venting of the hull if you install an outboard engine on your boat. Be sure to meet these regulations for safety reasons. Gasoline fumes are heavy and will accumulate in the low places of the boat’s hull if venting is not properly installed.