Why do 2 stroke diesel engines pollute more than 4 stroke diesels?

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Two-stroke engines produce a lot of pollution because the fuel air mixture in them gets contaminated with the engine’s lubricating oils. Simultaneously the combustion chamber draws in the contaminated mixture as exhaust gases are expelled through an exhaust port. Some of the fuel and oil gets mixed with the exhaust resulting in a single engine is contributing towards pollution greater than a four stroke engines.

two-stroke engines, unlike four strokes, don’ t have a system of valves that open and close in the exact moment, they have a set of intake and exhaust ports that are far less efficient. This leads to fresh mixture escaping (to an extent) thru the exhaust ports, which leads to more contamination. On top of that, you have oil in the mix, which makes things even worse.





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