Abstract: An internal combustion engine comprising a cylinder block which defines a cylinder, a crankshaft bearing supported at least in part by the cylinder block, a crankshaft which is rotatably supported by the crankshaft bearing, a piston slidably housed in the cylinder, a connecting rod having one end connected to the piston and having an opposite end connected to the crankshaft, a cylinder head mounted on the cylinder block, a camshaft at least partially supported by the cylinder head for rotation relative thereto, an oil pump having an outlet, a first oil conduit communicating between the oil pump outlet and the crankshaft bearing, an oil filter communicating with the first oil conduit for filtering oil only in the first oil conduit, and a second oil conduit communicating between the oil pump outlet and the camshaft, oil in the second oil conduit being unfiltered between the pump outlet and the camshaft.

Abstract: Disclosed herein is a carburetor including a member defining an air induction passage including a downstream portion, an upstream portion, and a venturi located between the downstream portion and the upstream portion, a member defining a fuel chamber, a fuel well located in the air induction passage defining member, extending in the fuel chamber, and communicating with the fuel chamber, a high speed nozzle located in the fuel well and communicating with the venturi, and an enrichment fuel pump including a cover fixed to the fuel chamber defining member, a diaphragm located between the cover and the fuel chamber defining member and defining a fuel pumping chamber and a variable pressure chamber, a duct communicating between the variable pressure chamber and the downstream portion of the air induction passage downstream of the throttle valve, an inlet conduit communicating between the fuel chamber and the fuel pumping chamber and including an inlet check valve permitting in-flow into the fuel pumping chamber an

Abstract: Disclosed herein is an outboard motor comprising a cylinder block including a lower horizontal drive shaft housing mounting surface, and a cylinder head mounting surface extending upwardly from the drive shaft housing mounting surface, a drive shaft housing including a peripheral outer surface including an upper end, a cylinder block mounting surface at the upper end, and a portion extending rearwardly from the cylinder block mounting surface and having therein a vertically open bore located forwardly of the outer surface, and a cylinder head comprising a cylinder block mounting surface fixed to the cylinder head mounting surface and including vertically spaced first and second recesses adapted to respectively form portions of first and second combustion chambers and respectively including first and second exhaust ports, a bottom surface extending transversely rearwardly from the cylinder block mounting surface of the cylinder head, a projection extending downwardly from the bottom surface and into the bore,

Abstract: An integrated induction system for providing fluids to the cylinders in an engine comprises a casing adapted for mounting on the engine. The casing has an air inlet and a plurality of fluid outlets. A plurality of air tubes are disposed within the casing so that air entering the air inlet flows through the air tubes and respective fluid outlets to the cylinders. A fuel injection assembly is mounted within the casing to inject fuel into the air exiting the air tubes adjacent each of the fluid outlets causing a mixture of air and fuel to enter the respective cylinders.

Abstract: An integrated induction system for providing fluids to the cylinders in an engine comprises a casing adapted for mounting on the engine. The casing has an air inlet and a plurality of fluid outlets. A plurality of air tubes are disposed within the casing so that air entering the air inlet flows through the air tubes and respective fluid outlets to the cylinders. Other fluid delivery systems, such as a fuel injection assembly, are mounted within the casing. A temperature sensor is also mounted within the casing.

Abstract: An integrated induction system for providing fluids to the cylinders in an engine comprises a casing adapted for mounting on the engine. The casing has an air inlet and a plurality of fluid outlets. A plurality of air tubes are disposed within the casing so that air entering the air inlet flows through the air tubes and respective fluid outlets to the cylinders. A fuel injection assembly is mounted within the casing to inject fuel into the air exiting the air tubes adjacent each of the fluid outlets causing a mixture of air and fuel to enter the respective cylinders. Provision is made for venting the casing when the pressure therein reaches or exceeds a predetermined limit.

Abstract: An integrated induction system for providing fluids to the cylinders in an engine comprises a casing adapted for mounting on the engine. The casing has an air inlet and a plurality of fluid outlets. A plurality of air tubes are disposed within the casing so that air entering the air inlet flows through the air tubes and respective fluid outlets to the cylinders. A fuel injection assembly is mounted within the casing to inject fuel into the air exiting the air tubes adjacent each of the fluid outlets causing a mixture of air and fuel to enter the respective cylinders. Connected to the fuel injection assembly is a carrier upon which are mounted induction system components. The casing is mounted on distribution mountings which are connected to the engine. The distribution mountings have passages to allow communication between air and fuel contained within the casing and the cylinders, and to allow communication between a supplemental fluid source and the cylinders.

Abstract: A fuel injection assembly for an engine comprises a fuel injector having an injector outlet and a nozzle having a nozzle passage with a nozzle inlet and outlet. The nozzle passage includes a converging portion adjacent the nozzle inlet and a diverging portion adjacent the nozzle outlet. The fuel injection assembly further comprises a nozzle support for attaching the nozzle to the fuel injector so that the injector outlet registers with the nozzle passage adjacent the nozzle inlet enabling injection of fuel from the fuel injector into the nozzle passage. The nozzle has a nozzle port adjacent the nozzle inlet enabling the establishment of an air flow which enters the nozzle passage adjacent the nozzle inlet and exits the nozzle passage through the nozzle outlet. At least a portion of the air flow in the nozzle passage is sonic enabling the fuel injected into the nozzle passage to mix with the sonic air flow and be carried by it through the nozzle passage and the nozzle outlet.

Abstract: An integrated induction system for providing fluids to the cylinders in an engine comprises a casing adapted for mounting on the engine. The casing has an air inlet and a plurality of fluid outlets. A plurality of air tubes are disposed within the casing so that air entering the air inlet flows through the air tubes and respective fluid outlets to the cylinders. A fuel injection assembly is mounted within the casing to inject fuel into the air exiting the air tubes adjacent each of the fluid outlets causing a mixture of air and fuel to enter the respective cylinders. Connected to the fuel injection assembly is a carrier upon which are mounted induction system components. The casing is mounted on distribution mountings which are connected to the engine. The distribution mountings have passages to allow communication between air and fuel contained within the casing and the cylinders, and to allow communication between a supplemental fluid source and the cylinders.

Abstract: Modulated tuning intake systems for multi-cylinder internal combustion engines are described wherein dual plenums are each connected to essentially half the engine cylinders and tuned to provide enhanced charging efficiency in a predetermined, normally lower, range of engine speeds. A controlled valved connector or tube is provided between the plenums to effectively modify or eliminate their separate character by joining them at other selected engine speeds, such as the middle and higher speed ranges, thus providing enhanced charging efficiency at these speeds and obtaining improved volumetric cylinder charging efficiency over all, or a major portion, of the engine operating speed range.