A four-stroke engine (10) employs engine vibration for lubricating engine components. The engine vibration induces a ripple in a surface portion of the oil in an oil reservoir (38), which is located within a crankcase (26) of the engine (10). The oil rippl...

Piston stroke recognition methods for small internal combustion engines, such as single and two cylinder engines, in which the ignition-related trigger pulses corresponding to the engine cylinders are the only input signal used for stroke recognition.

An evaporative emissions control system (30a, 30b) for small internal combustion engines (32) includes a control valve (66a, 66b) associated with a fuel line (62) and with a vent line (64) which each connect the fuel tank (54) to the carburetor (34). When ...

An engine with a variable compression ratio includes a connecting rod connected to a piston, a first arm turnably connected to the connecting rod and to a crankshaft through a crankpin, a second arm integrally connected to the first arm, a control rod turn...

A centerless recoil starter (26) in a small internal combustion engine (14) having a blower housing (28), a flywheel (36), and a crankshaft (38). The centerless recoil starter generally includes an annular cover (30) mounted to the blower housing and defin...

A carburetor having a plurality of restricted fluid flow paths upstream of a fuel and air mixing passage to inhibit the passage of large fuel vapor bubbles through the fuel paths and to the fuel and air mixing passage. Desirably, the restricted flow paths ...

A capacitor discharge engine ignition system includes an ignition coil having a primary winding and a secondary winding for coupling to an engine ignition spark plug. A first electronic switch has primary current conducting electrodes in circuit with an ig...

A capacitor discharge engine ignition system that includes an ignition coil having a primary winding and a secondary winding for coupling to an engine ignition spark plug. A first electronic switch has primary current conducting electrodes in circuit with ...

A detachable working machine throttle lever is provided with a main body (25, 35), a rotative lever member (29) to which a wire (21) from an engine (3) is connected, and an engine stop switch (23). When the lever member (29) is rotated in one direction, an...