Re: testing a motor without a prop Home › Forum › Ask A Member › testing a motor without a prop › Re: testing a motor without a prop outboard315Replies: 197Topics: 16 June 11, 2017 at 2:15 pm #59465 It is not recommended but I believe if you keep it below half throttle you should be ok. With the JW motors they changed props to stop them from over revving on light canoes.