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US 5,072,809 AGranted
Lubricating device for four stroke outboard motor
AssigneeSanshin Kogyo Kabushiki Kaisha
InventorYasuhiko Shibata
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AssigneeSanshin Kogyo Kabushiki Kaisha
InventorYasuhiko Shibata
Estimating the term…
A number of embodiments of outboard motors including dry sump lubricated four cycle internal combustion engines. The dry sump lubrication system includes a scavenge pump for drawing lubricant drained from the engine lubricating system through an inlet port and returns it to a dry sump reservoir through an outlet port and a pressure pump that draws lubricant from the dry sump lubricant reservoir through an inlet port and delivers it the engine lubricating system through an outlet port. At least one of the ports of each of the pumps is positioned above the normal lubricant level in the lubricant reservoir when it is filled with the normal volume of lubricant so as to insure that lubricant will not drain back into the engine when the pump system is not operating. Various arrangements for achieving this result and for cooling the lubricant are described.
An outboard motor comprised of a power head having a powering internal combustion engine have an internal lubrication system, a propulsion unit driven by said engine for propelling an associated watercraft, means for mounting said outboard motor upon a hull of the associated watercraft for movement between a plurality of trim adjusted positions and a tilted up out of the water position, a dry sump lubricant reservoir for containing lubricant for lubricating said engine, a scavenge pump driven by said engine and having an inlet port communicating with the engine internal lubricating system for receiving lubricant therefrom and an outlet port for returning lubricant to said dry sump lubricant reservoir, and a pressure pump having an inlet port for drawing lubricant from said dry sump lubricant reservoir and an outlet port for delivering lubricant under pressure to the engine internal lubricating system, at least one port of each of said pumps being positioned above the normal lubricant level within said dry sump lubricant reservoir in all positions of said outboard motor for precluding the draining of lubricant from said dry sump lubricant reservoir back to the engine when the engine is not running.
An outboard motor comprised of a power head having a powering internal combustion engine having an internal lubrication system, a propulsion unit driven by said engine for propelling an associated watercraft, means for mounting said outboard motor upon a hull of the associated watercraft for movement between a plurality of trim adjusted positions and a tilted up out of the water position, a dry sump lubricant reservoir for containing lubricant for lubricating said engine, a scavenge pump driven by said engine and having an inlet port communicating with the engine internal lubricating system for receiving lubricant therefrom and an outlet port for returning lubricant to said dry sump lubricant reservoir, a pressure pump having an inlet port for drawing lubricant from said dry lubricant reservoir and an outlet port for delivering lubricant under pressure to the engine internal lubricating system, each of said pumps having check valve means in its discharge side for precluding flow back to the pump from which its output port when the engine is not running.
Dependencies are inferred from the claim text.