Patent ID: 6021748
Filing Date: 2000-02-08
Classification: F02B,F02D,Y02T

Abstract:
A control for a planing-type boat having an engine powering a water propulsion device, said engine having at least one combustion chamber, an exhaust port leading from said combustion chamber, an exhaust timing valve cooperable with said exhaust port, said exhaust timing valve moveable between a first retracted position and a second extended position where in said second position a flow of exhaust through said exhaust port has a shorter duration than when said valve is in said first position, an engine speed sensor for sensing the speed of said engine, and a drive unit arranged to move said exhaust timing valve, said control arranged to hold said exhaust timing valve in said second position when sensed engine speed is in a range below a first engine speed range, to rapidly move said exhaust timing valve with said drive unit from said second position to a new position towards said first position at a predetermined higher engine speed above said first engine speed range and to hold said exhaust timing valve in said new position when said sensed engine speed is in a second range the lower end of which comprises said predetermined higher engine speed.