jack plates and steering connection.

Discussion in 'Propulsion' started by valvebounce, Apr 17, 2017.

  1. valvebounce
    Joined: Dec 2010
    Posts: 447
    Likes: 9, Points: 18, Legacy Rep: 124
    Location: manchester uk

    valvebounce Senior Member

    I have a 14ft f/glass boat with a short shaft transom.
    I am about to collect a 25hp Johnson longshaft 2 stroke to put on it.
    At present I have a classic 1963 18hp Evinrude short shaft on it.Which runs as sweet as a nut.It has remote controls fitted,and steering.
    If I fit the 25hp it will go straight on,but the cavity plate will be 4" to 5"lower than the hull.The hull is almost flat bottomed at the stern,with a "V"planing hull forward.
    The boat has a splashwell.
    If I fit a jackplate,the steering rod will have to fit at 45% from the universal ball in the splashwell to the connection on the outboard.
    Will the universal rotating ball handle the angle,or will I need to fabricate an extension from the motor connection to the steering rod connection that is level with the present position of the ball?The height difference will be 4" to 5".
     
  2. gonzo
    Joined: Aug 2002
    Posts: 13,078
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    Location: Milwaukee, WI

    gonzo Senior Member

    The angle will increase as the motor turns, most likely causing it to bind and/or bend permanently. The anti-ventilation plate will cause a lot of drag if you run it submerged, so that is not a good option. I think that an extension to bring the steering down will be the best. Those motors have a plate bolted to the front bracket, so it shouldn't be too hard to make a longer plate.
     
  3. valvebounce
    Joined: Dec 2010
    Posts: 447
    Likes: 9, Points: 18, Legacy Rep: 124
    Location: manchester uk

    valvebounce Senior Member

    I thought that might be the answer G,I made a modified one for the 18hp Evinrude,so,like you say
    A longer one would be the answer.This 25hp is a great buy,So a bit of modifying will be worth it.
     
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