| 摘要 |
PURPOSE: An engine is provided to prevent the inflow of lubricating oil into an intake system by employing a breather mechanism for discharging blow-by-gas from a crank case. CONSTITUTION: An engine(21) comprises a breather mechanism(25) which includes a breather passage(51) opened to a crank case(35), a breather chamber(52) which is connected to the crank case through the breather passage, and a breather valve(53) which is installed in an inlet end of the breather chamber and opened when the internal pressure of the crank case exceeds the set value to let blow-by-gas flow into the breather chamber from the crank case. When the engine is laid down, lubricating oil is blocked from flowing into the breather chamber through the breather passage. When the engine is in a standing position(P1), the outlet end(58b) of the breather passage is located above the inlet end of the breather passage. |
