Idle speed control for fuel injection outboard motor

摘要

An outboard motor has an idle speed control in an induction and fuel injection system. The idle speed control controls the rate of flow of air through a bypass passage into the induction system to help improve engine performance. The bypass passage bypasses flow through the throttle body to increase the air flow while the throttle body is either closed or in a wide open position. Of course, the arrangement also can be used to increase the air flow in other orientations of the throttle valve. The bypass passage also is connected to a vent from a vapor separation tank such that vapor from the gas-filled vapor separation tank passes into the bypass air flow and is admitted into the intake system downstream of the throttle valve. The bypass air flow is subdivided between a number of the intake pipes. The bypass arrangement thus advantageously introduces a subdivided amount of ventilation air from the vapor separation tank into each of the plurality of combustion chambers formed within the engine. Thus, the arrangement substantially equalizes the amount of vent air being introduced into each combustion chamber through the bypass arrangement.