Crankcase breather mechanism

摘要

An improved engine construction is disclosed having a valve train including valves and corresponding valve stems for controlling the intake and exhaust ports, cams for imparting reciprocating motion to the valves by way of the valve train, and a valve spring for biasing each valve toward its closed position and the valve train into tracking relation with the cam. The only element of the valve train coupling a cam to a stem is a cam follower with a depression for receiving the corresponding stem end and a cam engaging surface opposite the depression with the cam follower being held captive intermediate the stem and cam solely by the spring biasing of the stem toward the cam and the engagement of the stem end and the depression. A feature of the engine resides in a combination crankcase breather mechanism and oil fill cap which due to its remote location from the engine crankshaft as well as the tortuous air flow path through the cap to the atmosphere minimizes the egress of oil from the engine through the breather mechanism.