Why are 2-strokes sold for boats and manufactured overseas?
The U.S. regulations on marine (maritime) emissions are less stringent than for road and industrial vehicles. The 2-stroke diesel is simpler and has proven reliability; reliability concerns are greater for boats than for road and industrial vehicles. “Dirty” 2-stroke diesels are easier to manufacture without advanced manufacturing technologies — one of the reasons the 2-stroke diesel has been around nearly unchanged for 70 years or so (I am simplifying) and competing 4-strokes have been relatively recent on the scene. By the way, if you double the number of parts in a system, then to get the same reliability you need to quadruple the reliability of each individual part.
