Patent ID: 7314115

Claim:
A lubricating system for an internal combustion engine comprising: a lubricating oil tank being integral with a crankcase and being partitioned from a crank chamber by a tank partition wall projecting from an inside wall of said crankcase; a recovery pump by which lubricating oil dropping to and dwelling in a bottom portion of said crank chamber after lubricating individual portions of said internal combustion engine is sucked through a pump suction port opened in said bottom portion of said crank chamber and is fed to said lubricating oil tank; a supply pump for supplying said lubricating oil from said lubricating oil tank to said individual portions of said internal combustion engine; an overflow oil passage wall projecting from said inside wall of said crank chamber extends downwardly; and an overflow oil passage formed by said tank partition wall and said overflow oil passage wall, said overflow oil passage wall extending substantially parallel to said tank partition wall, through which said lubricating oil that flows over the upper edge of said tank partition wall of said lubricating oil tank is led to said pump suction port of said recovery pump.