I have a 1978 17' fiberglass terry fishing boat with a 115hp mercury inline 6 (1978) . Brought it last year without prop. <br /><br />I having issues taking off. I trottle down 7 out of 10 times the boat with not plane and the engine just revs up. I no a motor person so any help is appreciated. <br /><br />Prop right now is 13.25X15<br /><br />Thanks