Wonder if the key or whatever holds the quadrant in position might have fallen out or sheered. Had that happen to me after a haulout when the yard didn't reinstall the bolt that locked the quadrant to the shaft. The cinch bolts on the quadrant held the quadrant in position from Santa Cruz till we began surfing into SF Bay. Suddenly boat wouldn't turn to port. Tried using the emergency tiller but couldn't over power the cocked quadrant. Didn't realize I had to disconnect the steering cables to be able to use the E tiller. Had just a little port rudder so managed to get into the marina and into the slip by doing 180s and 270s to starboard.