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Daysailor wannabe cruiser
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Discussion Starter · #1 · (Edited)
I've been looking for discussions on outboard propeller options for displacement(sailboat) hulls. I have a nissan xtra long shaft 6hp that propels my 2200lb sailboat. The stock propeller is a 8" pitch prop but now they have "elephant ear" "high thrust" propellers for that motor that are for sailboats. My current setup obviously works fine 90% of the time but when there is tide and chop I was thinking that a smaller pitch wider diameter prop would help me maintain speed against the waves. The prop is 69.99 with free shipping so that's not even one boat dollar.

Thoughts?????
 

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I have a J24 3000#+ it moves the same with a 6Hp Johnson twin OR a 4 Hp Tohatsu one cylinder :)

I dont really get and more speed with the 4 Hp much above 5/8 throttle (5 to 6 knots) depending on how much weight is in the stern and it has no problem pushing the boat in 20+ knots of wind


They make a 7" that would allow more RPM BUT the high thrust that fits is so over priced i have not bothered
 

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High Thrust Props

There are advantages to dropping the pitch in favour of more diameter.
In my case it involves much more horsepower but the concept is the same.
I have a MacGregor with the 50Hp outboard on the back and I too was looking for less speed and more thrust. The prop that came with it was a 3 X 10.25 X 13 and that got me into the 5800 rpm range but I am sure there was a lot of slippage because I did not get 13 pitch speed that I should have. Since my desire was less speed and more thrust I bought a Solas Alcup 4 X 11.4 X 10.5 propeller. The extra ear and larger diameter added more water surface contact which translated into more thrust at lower speeds. Of course my top speed dropped but my low to mid range speeds at the same rpms as the three blade actually increased somewhat, not a lot but a bit better. I also gained much more control at low speeds and reverse when docking which was an added bonus.
If you can get a four blade for your engine or even the bigger dog eared prop you will lose some high end speed but make up for it at low end thrust and manueverability. You will move more water and have better control.
Another little change you can look at is cupping. Some props have a little cup ridge on the trailing edge of each blade which helps the prop get a better grip on the water, the Solas Alcup has this feature. At any rate a prop that moves more water at slower speeds will enhance your low end power and manueverability.
 
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