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MotorGround >> Boat guys... Propeller?


6/22/09 1:28 PM
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white belt
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Edited: 06/22/09 1:29 PM
Member Since: 1/1/01
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Well I had the fortune of losing my prop last night. Any suggestions on what size and pitch to get? The boat is a 11 foot Walker bay (zodiak type) and the motor is a 02 Johnson 15hp. I normally carry 4-500lbs weight. Oh and I run a stingray Jr as well.
6/27/09 11:09 AM
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Ponyboy
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Did it slip causing you to stop and then it came off as you coasted to a stop or did you get too close to rocks?

Think about how many rpms the engine could go to with the old prop when you had the boat loaded how it will normally be run and talk to someone smart or look it up and see if your boat was overpropped or underpropped.....but only if your last prop was in pretty good shape.

If the old prop was nicked and dented, then any information on rpms....etc will be tainted by the condition of the old prop.

This is your chance to correct it if it is off.

Stainless is the shit but might not make a difference on an engine that small and they are like magnets to thiefs.
6/28/09 1:06 PM
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white belt
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Thanks Pony, I did a hell of a lot of reading, found a great website forum on www.iboats.com Ended up getting a 9 1/4 diameter and 10" pitch. I'll see how that works out rpm and planing wise and make a change from there if necessary. There is a prop wizard out there for the bigger boats but no info for my application.
8/20/09 12:46 AM
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White347LX
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How many blades?

I just replaced the wore out factory 2 blade prop on my 74 Merc 20 with a 3 blade because the rubber slip ring burned out. I think it's the same size and pitch as you described. It planes out faster and at a lower speed but lost a couple MPH on the top end.
8/21/09 2:39 PM
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white belt
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It is a 3 blade, never saw a 2 blade option, just 3 or 4. After running it for bit I am very happy with the choice. I do notice though depending on load in the boat, shimming the motor up makes a huge difference in top end. Also with now that I have it trimmed out well I find I can't inflate my air floor enough, the swell works it way back deforming the floor and when it goes out the back the prop slips (cavitates). Now I fin I just sit on the swell to hold it back.
8/23/09 7:00 PM
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Ponyboy
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I'd take the plane out at slightly lower speed over having a couple of people in the boat and not reaching plane.
8/26/09 11:49 AM
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white belt
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Absolutely, if I were buying again I would get 11 pitch. Going to have to buy a new pump though to get the floor up to a higher pressure to truly check performance.
8/28/09 3:34 AM
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White347LX
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I'm buying another 2 blade prop because the engine is just screaming with this 3 blade on there. Most of my boating is just wide open up and down the Mississippi River from the boat ramp to my trotlines so I think the top end is what I'm most concerned with. This 3 blade is nice when the wind picks up and I'm bouncing across 3' waves but I try to NOT be out there in those conditions with a 16' jonboat. lol

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