Discussion in 'Jet Drives' started by sandrail, May 10, 2006.

  1. sandrail
    Joined: May 2006
    Posts: 6
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    Location: San Jacinto, CA

    sandrail Junior Member

    Good morning. I thought my last question would be very hard to answer since there being so many models of boats, but thanks for looking. I have another question, The jet boat I bought had a very small rudder on the jet but at sometime it must have broke off, is there anyway to install another or is it best to just forget about it? Some say it helps with the steering is this true or does it not help enough to replace it? Thanks Alot Richard PS As you can see I am a novice concerning jet boats:cool: :cool:
  2. marshmat
    Joined: Apr 2005
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    Location: Ontario

    marshmat Senior Member

    Not all jets have these rudders, or "turning fins" as the builders sometimes call them. Their purpose is to keep the boat tracking smoothly through a turn at speed, rather than sliding sideways.
    If your drive's manufacturer is still around, you can probably get a replacement from them with a little patience and a few hundred dollars. If your boat tracks well in high-speed turns as it is, the fin might not be necessary with your hull shape.
  3. lee armistead
    Joined: May 2006
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    Location: Ruskin. FL. 33570

    lee armistead Junior Member

    The turning fin is designed by the manufacturer to function as a turning devise for their type of jet drive. They have tested them to provide you with good steering control under normal operating conditions. Jet boats are very hard to control at slow speeds but out perform prop jobs a top end. Welcome to the world of jet boating. I have designed and installed a separate rudder system as a "see what it will do" situation. More work that its worth. Stick with the manufacturer recommendations. You'll find Hamilton jet drives on the web (they purchased Jacuzzi) and go directly to Berkley jet drives for other answers to this question. Hope my feed back helps. Lee Armistead

  4. Seabrooke22
    Joined: Apr 2010
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    Location: Melbourne, Australia

    Seabrooke22 New Member

    Jets and rudders and stuff.

    Sorry Lee but that it just plain wrong. Unless, of course, the engine is switched off which is where the rudder can come in very handy.

    Richard, so long as you have reverse on your jet you don't need to be too concerned. Here are some tips.

    Engine off: No thrust = no steering. :( A rudder can assist here but only a little as the rudder (or steering fin) on a jet is normally quite small.

    Engine running - slow speed or docking: For OUTSTANDING:!: :!: steering control at slow speeds, leave the engine just above idle and use the reversing bucket control together with your steering wheel. You will have total control from ahead thrust through neutral (with full steering) to reverse thrust. It takes only a little practice and you will be turning the boat at a stand still within its own length, walking it directly sideways or any other direction you want to go. :cool:

    So, get the boat out and do a bunch of low speed practice then you will be able leave the engine running until you are gently alongside the dock and your deck hand is sorting out the ropes.

    For an example, go to youtube and search "Boat Ballet" You will be amazed with the control. To make it easy, here is a link to the clip

    Cruising speeds: Jet - Prop.... no great difference here. A rudder won't really be all that noticable.

    High Speeds: A rudder can help with extra bite in the turns but you need to be VERY careful with the size of the rudder as too large a rudder will spin the boat around VERY quickly.:D

    Lee, I don't mean to be critical of you in any way but I hear so many people speaking of the limitations of jets when there are very few things that a jet boat can't do that a prop boat can...... except, of course, tear off prop blades, bend shafts, bend rudders in shallows, chop up legs and turtles and dolphins etc. etc. etc. but I don't find these to be things I need to be able to do. :D

    Richard, I do hope this helps. I see that this is an old thread and you have probably well and truly developed the skills I have mentioned already but I have only just joined the forum and came across this thread today.

    Cheers Gents,

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