Lubrication apparatus for four-stroke engine

摘要

A lubrication apparatus for a four-stroke engine that prevents lubrication failure from occurring around the crankshaft and reliably prevents oil from remaining in a valve operating chamber includes: an intake part positioned below the level of an oil A in an oil reservoir even if the oil reservoir is tilted and the level of the oil A changes; an oil feeding passageway that sucks up the oil A from the intake part and supplies the oil A to the crank chamber; and an direct passageway that allows communication between a valve operating chamber and a crank chamber when a negative pressure is created in the crank chamber. Open end parts of the oil feeding passageway and the direct passageway which are open in the crank chamber are provided to open as the piston moves from a position near the top dead center to the top dead center.