Just returned from a two week trip and I was wondering. I had to motor sail to keep up with our group for part of the time. Wind was from behind as were the waves at about 4 feet. When topping a wave and surfing down the backside I would pick up about a knot to a knot and a half and the motor would change pitch. I though it might have been from cavitation. Since there has been much discussion about transmission damage from free wheeling props when just sailing, what about when surfing down the face of a wave while motor sailing?
