Emission preventing system of evaporated fuel for internal combustion engine

摘要

An internal combustion engine in which a fuel evaporated in a fuel tank is stored in a crankcase, including a system for preventing the evaporated fuel from being emitted into the atmosphere. The crankcase is in communication with an intake passage through a breather passage and with the atmosphere through an atmospheric vent. Change-over means provides communication between the crankcase and the intake passage while the engine is running, and vents the crankcase to the atmosphere when the engine is stopped.