Patent ID: 6491032
Filing Date: 2002-12-10
Classification: F02B,F02D

Abstract:
A marine internal combustion engine comprising a cylinder block defining a cylinder bore, a cylinder head assembly fixed at one end of said cylinder block enclosing one end of said cylinder bore, a piston that reciprocates in the cylinder bore, a connecting rod pivotally connected to said piston, a crankshaft rotatably journaled and driven by said piston through said connecting rod, said piston, said cylinder bore and said cylinder head forming a combustion chamber, at least one air intake passage being at least partially defined in said cylinder head, a plenum chamber in fluid communication with said air intake passage, an intake valve positioned between said air intake passage and said combustion chamber, a throttle valve pivotally mounted in said air intake passage between said plenum chamber and said cylinder head assembly, a fuel injector mounted to inject fuel toward said combustion chamber, a bypass passage in fluid communication with said plenum chamber and in fluid communication with said air intake passage downstream of said throttle valve, an ISC valve positioned along said bypass passage, an engine speed sensor positioned to detect a speed of said crankshaft, an actuator connected to said ISC valve, an intake pressure sensor positioned along said intake passage between said throttle valve and said intake valve, a throttle position sensor adapted to detect a position of said throttle valve, an ECU electrically connected with said engine speed sensor, said intake pressure sensor and said throttle position sensor, said ECU adapted to control a fuel injection amount in response to a first set of engine running conditions, and said ECU signaling said actuator to substantially fix said ISC valve in an open position over a range of values of a second engine running condition, above a preset value of the second engine running condition.