Both 2011 3.5-horsepower Tohatsu outboards are four-stroke, single-cylinder engines. These engines offer two valves and a 5.22-cubic-inch piston displacement. Bore and stroke on these engines is 2.17 by 1.42 inches.
The MFS3.5BS and MFS3.5BL models employ a single Venturi carburetor. They both are designed for use with a composite 7.4-inch (diameter) by 7.0-inch propeller. They both also feature a 0.26-gallon fuel tank, stainless steel housing for the water pump and zinc coatings in water passages.
There are only a few differences between the two models of Tohatsu 3.5-horsepower outboards. The MFS3.5BS model outboard is designed with a 15-inch transom and weighs 41 pounds, while the MFS3.5BL model is designed with a 20-inch transom and weighs 43 pounds. MFS3.5BS models are available for around $929.99 and MFS3.5BL models can be found for around $959.99, as of late 2010.