Hydraulically, servo-operated, automatic, change over valves, utilized in a two ram hydraulic steering gear, serve to __________.

Correct Answer: Option A — prevent either main pump from being hydraulically motored when idle by cross pressure flow

Servo-operated change-over valves in hydraulic steering systems isolate the idle pump from the active pump's discharge pressure. This prevents the idle pump from being 'motored' or driven backward by the system pressure, which would cause mechanical damage, overheating, and potential loss of steering control during a pump change-over operation.