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Old 27-07-2009, 21:41   #1
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Outboard Directional-Control Issues

I bought a 27' sailboat, 2.5' draft (centerboard up) with an 8hp outboard mounted to the right of the rudder. The outboard is fixed and steering is done via the rudder. Initially I noticed the outboard was not fixed straight but was slightly clockwise. When stationary and starting to move forward I pivoted to port and when moving in reverse i pivoted to starboard. I adjusted the motor to as close to straight-ahead as i could eyeballing it and still have the pivoting problem but maybe not so pronounced. Is this just a fact of life given the motor is offset to starboard and there is no propwash behind the rudder? If so should I rotate and lock the motor slightly counter-clockwise to counter this?
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Old 28-07-2009, 02:36   #2
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Best way is to try and see what works best for your boat.
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Old 28-07-2009, 04:27   #3
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With the engine off the centerline and the boat stationary you will be influenced by propwalk and the offset thrust of the engine.

Once flow begins over the rudder and keel you will have longitudinal stability. If you offset the thrust to correct at low/zero speed you will likely be fighting the opposite effect at higher speeds.

What hp does the engine produce?
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Old 28-07-2009, 05:07   #4
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I noticed this on my ODay 222 w/ 6 hp outboard mounted offset to stbd. If I got it going at desired speed, centered the tiller, and then adjusted the angle of the outboard, I could completely eliminate the tendency to veer off one way or another.
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Old 28-07-2009, 06:01   #5
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It's an 8hp. I've read that propwalk isn't much of a factor with outboards because of the smaller prop and higher rpms. Is the pronounced pivoting just a fact of life if the engine is off the centerline? Can anyone verify this?

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Originally Posted by Ex-Calif View Post
With the engine off the centerline and the boat stationary you will be influenced by propwalk and the offset thrust of the engine.

Once flow begins over the rudder and keel you will have longitudinal stability. If you offset the thrust to correct at low/zero speed you will likely be fighting the opposite effect at higher speeds.

What hp does the engine produce?
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