Patent ID: 6883320

Claim:
A method of regulating a valved intake flow through a cooler and a cooler bypass to an engine intake, the method comprising: a. using a hydraulically powered actuator to change the valved flow; b. adjusting the hydraulic actuator with a spool valve positioned by a proportional solenoid to infinitely adjust the valved flow; c. controlling the proportional solenoid in response to a sensor of engine temperature; d. arranging a spring to move with changes in the valved flow; e. transmitting a feedback force to the spool valve via the spring; and f. responding to a change of current to the proportional solenoid caused by a change in engine temperature detected by the sensor by moving the spool valve to change flow of hydraulic fluid to the hydraulic actuator to adjust the valved flow and change the feedback transmitted by the spring to the spool valve.