A two stroke marine diesel is very different from a gasoline two stroke. Only intake is done through the cylinder wall ports and exhaust is through poppet valve

A two stroke marine diesel is very different from a gasoline two stroke. Only intake is done through the cylinder wall ports and exhaust is through poppet valves at the top. (Uniflow) Also lubrication is done like in four strokes. There is no crankcase compression, instead turbochargers are used.