Re: 18ft Lund 50F Yamaha Prop???
Steelespike, I am an advocate of safety too, but there are unique situations here in Alaska and the Yukon where things can't always go by the book. For example, there are branches hunted on the mighty Yukon River which are extremely shallow, narrow, and inhospitable. They are only accessable by boat and over 1,000 miles from civilization. This requires a small boat with good power that can haul much gear and fuel. Many boats travel these waters, and every one of them is homemade or modified for the conditions. I highly doubt you will find hp ratings or factory floatation on these boats. We hunt with a homemade fiberglass over plywood Carolina Skiff looking thing with twin commercial outboards and a spare on deck. Because of the conditions we usually come home with two of the three outboards needing repair. We bring 6 55 gallon drums of gasoline and can haul 3 70+" moose and all gear for a month. Hp ratings? Can't have enough. Coast Gaurd approved floatation? Where do you put it? I do wear a life jacket, but the chances of survival in these remote areas are probably zero.<br /><br />Now, on to props. The 4-stroke T-50 is a high-thrust and has a larger gear case than the 2-stroke 50. It has a high 2.33 gear reduction. So 10" and 11" diameter props will not work. I think your dealer is mistaken. The best way to prop your boat is with a tachometer and a speedometer. Your engine must maintain between 5,000 and 6,000 rpm.<br /><br />For the light load, I would suggest a 13 3/4" diameter by 15" pitch. You might get more speed out of a 13 1/4" by 17 if you can keep the rpms up.<br /><br />The 13 3/4" by 15" would probably work for your all-round use, but a 13 1/4" by 15 would help with the added load.<br /><br />For the heavy load, I would use the smallest diameter 13 pitch prop available. Say a 13 5/8" by 13. I don't think you can drop below a 13 pitch prop with the T-50. <br /><br />Good luck, and like Steelespike said, be careful.
