Abstract: A fuel injection type multiple cylinder engine unit includes an oil lubricating device including an oil tank and the oil in the oil tank is pumped up by a pump having an oil drain side to which pipes are connected for supplying the oil near the injectors. Each of the pipe has a front nozzle portion disposed at a portion near the front fuel jetting end of the injector and the fuel and the oil independently injected in an intake device of the engine unit are atomized and mixed with suitable mixture ratio. The intake device of the engine unit is provided with a surge tank which comprises a main surge tank formed integrally with an inlet manifold and sub-surge tanks formed by forming recesses between the respective adjacent intake pipes in association with the inlet manifold. The main surge tank and the sub-surge tanks are communicated with each other to thereby increase the total inner volume of the surge tank.

Abstract: A fuel injection system of an outboard motor is provided with a vapor separator as a fuel tank disposed in the outboard motor and the system includes a fuel return pipe connected to the vapor separator, a fuel supply pipe connected to the vapor separator for supplying fuel to the fuel injector and a vent means connected to the vapor separator. The vent means is connected to a port formed to the throttle body through a connection hose on an upstream side of the throttle valve. The port formed to the throttle body is opened at a portion at which an air flows in the throttle body with highest flowing speed and upstream and downstream sides of the throttle valve are communicated through a by-pass passage which is provided with a port on the upstream side of the throttle valve opened near the port formed to the throttle body.

Abstract: A fuel injection type multiple cylinder engine unit includes an oil lubricating device including an oil tank and the oil in the oil tank is pumped up by a pump having an oil drain side to which pipes are connected for supplying the oil near the injectors. Each of the pipes has a front nozzle portion disposed at a portion near the front fuel jetting end of the injector and the fuel and the oil independently injected in an intake device of the engine unit are atomized and mixed with suitable mixture ratio. The intake device of the engine unit is provided with a surge tank which comprises a main surge tank formed integrally with an inlet manifold and sub-surge tanks formed by forming recesses between the respective adjacent intake pipes in association with the inlet manifold. The main surge tank and the sub-surge tanks are communicated with each other to thereby increase the total inner volume of the surge tank.

Abstract: An apparatus for controlling an ignition timing for a marine engine has a temperature sensor for detecting a cold or warm-up state of the engine and for outputting an ON/OFF signal, and has an ignition timing controller for receiving the signal from the temperature sensor, for receiving signals representing an engine rotational speed and a throttle opening degree which are sent from other sensors, and for setting an optimum ignition timing.

Abstract: A fuel injection system for a multiple cylinder two-stroke cycle engine having a plurality of cylinders provided with intake manifolds, respectively, comprises a plurality of fuel injectors each operatively connected to its respective intake manifold, a controlling unit operatively connected to the fuel injectors for controlling fuel injection of the fuel injectors, and a unit operatively connected to the fuel injection controlling unit for detecting the revolution number or speed of the engine. The fuel injection controlling unit includes a micro computer for carrying out calculations in response to information from the engine revolution operation detecting unit so as to inject the fuel a plurality of times with equal angular intervals defined therebetween during one revolution of the engine, or the crank shaft, during the neutral and low revolution periods of the engine.

Abstract: A rotational speed control system for an engine includes controls for determining whether the throttle is closed beyond a predetermined position, whether the engine is mechanically loaded, and whether the engine rotational speed exceeds a predetermined speed. A control delays the ignition timing of the engine when the throttle is closed beyond the predetermined position, the engine is not mechanically loaded, and the rotational speed exceeds the predetermined speed.