Engine breather construction

A four stroke engine breather comprising a camcase cover including an inner surface, an outer surface including an endless upstanding peripheral wall defining a camcase cover chamber, a baffle dividing said camcase cover chamber into first and second sub-chambers communicating with each other, a passage extending between said inner surface and said first camcase cover sub-chamber for conveying an air/oil mist from the camcase to said camcase cover chamber, a partition having ends extending from said peripheral wall to partially define a sump sub-chamber within said camcase cover chamber, a restricted passage between said sump sub-chamber and said inner surface to afford drainage of oil from said sump sub-chamber to the camcase, and an oil drainage aperture located in said partition and communicating between said sump sub-chamber and said second sub-chamber, a wire mesh element in said sump sub-chamber, a plate engaging said upstanding peripheral wall of said camcase cover, said baffle, and said partition to further define said camcase cover chamber and including an aperture communicating through said plate with said second sub-chamber in said camcase cover chamber, a reed valve fixed relative to said plate and including a valve portion movable between positions closing and opening said aperture and being biased towards said closing position, and a breather cover including an end wall extending in generally parallel relation to said camcase cover, an endless peripheral wall extending in upstanding relation to said end wall and engaging said plate to define therebetween a breather cover chamber, a series of baffles extending in upstanding relation to said end wall and within said peripheral wall and engaging said plate to subdivide said breather cover chamber into a series of serially connected sub-chambers including a first sub-chamber communicating, when said valve is in the opening position, through said aperture in said plate with said second sub-chamber in said camcase cover chamber, and a last sub-chamber communicating with the atmosphere through an opening in one of said end wall and said peripheral wall of said breather cover.

An outboard motor comprising a cylinder head partially defining a camcase, a camcase cover further defining said camcase and including an inner surface, and an outer surface, and a breather including an endless peripheral wall extending from said outer surface of a said camcase cover in upstanding relation thereto and defining a camcase cover chamber, a baffle dividing said camcase case chamber into first and second sub-chambers communicating with each other, and a partition having ends extending from said peripheral wall to partially define a sump sub-chamber within said camcase cover chamber, a passage extending between said inner surface and said first camcase cover sub-chamber for conveying an air/oil mist from said camcase to said camcase cover chamber, and a restricted passage between said sump sub-chamber and said inner surface to afford drainage of oil from said sump sub-chamber to the camcase, a wire mesh element in said sump sub-chamber, a plate engaging said upstanding peripheral wall, said baffle, and said partition to further define said camcase cover chamber and including an aperture communicating through said plate with said second sub-chamber, a reed valve fixed relative to said plate and including a valve portion movable between positions closing and opening said aperture and being biased toward said closing position, and a breather cover including an end wall extending in generally parallel relation to said camcase cover, an endless peripheral wall extending in upstanding relation to said end wall and engaging said plate to define therebetween a breather cover chamber, and a series of baffles extending in upstanding relation to said end wall and engaging said plate and within said peripheral wall to subdivide said breather cover chamber into a series of serially connected sub-chambers including a first sub-chamber communicating, when said valve is in the opening position, through said aperture in said plate with said second sub-chamber in said camcase cover chamber, and a last sub-chamber communicating with the atmosphere through an opening in one of said end wall and said peripheral wall of said breather cover.

A four stroke engine breather comprising a camcase cover including an outer surface partially defining a camcase cover chamber including a first sub-chamber and a sump sub-chamber, an inlet passage through said camcase cover and communicating with said camcase cover chamber for conveying an air/oil mist from the camcase to said camcase cover chamber, a restricted oil drainage passage through said camcase cover and communicating with said sump sub-chamber for conveying oil from said sump sub-chamber to the camcase, an oil drainage aperture in said camcase cover and communicating between said sump sub-chamber and said first sub-chamber in said camcase cover chamber, a plate engaging said camcase cover to further define said camcase cover chamber and including an aperture communicating through said plate with said first sub-chamber in said camcase cover chamber, a reed valve fixed relative to said plate and including a valve portion movable between positions closing and opening said aperture and being biased toward said closing position, and a breather cover including a wall engaging said plate to define therebetween a breather cover chamber which includes a series of serially connected sub-chambers including a first sub-chamber communicating, when said valve is in the opening position, through said aperture in said plate, with said first sub-chamber in said camcase cover chamber, and a last sub-chamber communicating with the atmosphere through an opening in said breather cover wall.