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Equalizing hynautic steering

Discussion in 'Technical Discussion' started by JBP, Apr 15, 2018.

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  1. JBP, Apr 15, 2018
    #1
    JBP

    JBP New Member

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    Good Morning

    This steering is on a 62 Malcom Tennet power catamaran. We repowered the the boat last winter and and at high speeds 25-30 knots the boat turns super easy port and hard to recover to starboard. Rudders are toed out. I was going to decrease rudder toe to compensate ?

    This system does not use a link bar between the rudders years ago I seen rudder angles changed by shutting off valves at the cylinder and turning the helm for alignment, it was similar set up. Thoughts?

    Thank You
  2. Capt J, Apr 15, 2018
    #2
    Capt J

    Capt J Senior Member

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    Are you sure that both rams are steering to starboard at speed? There is a check valve in most steering rams and on the sea star these can go bad fairly often and they work fine in one direction but in the other direction either don't turn fully or start bleeding back and losing turn angle.
  3. JBP, Apr 15, 2018
    #3
    JBP

    JBP New Member

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    Yes they are staying in sync, I have a rubber indicator on both sides, running at low speed's is operating as normal as it always has last 3000 miles I put on it, new motors have increased the speed from 20 to 30 knots the problem seems to increase as you add speed, i'm perplexed why it wants to go one way more than the other, I was hoping this was a rudder angle issue and not a hull design issue
  4. Capt Ralph, Apr 15, 2018
    #4
    Capt Ralph

    Capt Ralph Senior Member

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    Both props spinning the same direction?
  5. JBP, Apr 15, 2018
    #5
    JBP

    JBP New Member

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    they are countering rotating both swinging away from each other
  6. Capt Ralph, Apr 15, 2018
    #6
    Capt Ralph

    Capt Ralph Senior Member

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    This steering is on a 62 Malcom Tennet power catamaran. We repowered the the boat last winter and and at high speeds 25-30 knots the boat turns super easy port and hard to recover to starboard. Rudders are toed out. I was going to decrease rudder toe to compensate ?

    This system does not use a link bar between the rudders years ago I seen rudder angles changed by shutting off valves at the cylinder and turning the helm for alignment, it was similar set up. Thoughts?

    Thank You[/QUOTE]
    Same problem at original or lesser speeds?
    Any rudder equipment messed with during engine replacment?

    You may (should) have a MSV at each rudder cylinder.
    2 brass nut/screws on top of each MSV. These are the more correct valves.

    I just use the pressure relief valve (250 psi) method.

    An easy experiment would be to turn the wheel over to hard std, then force another turn (pressure relive valve opens). This will sync both cylinders to their end (or rudder stop) travel.
    Then turn to the hard stop to port. Both cylinders should be at full travel or in sync against their stops.

    If your worried about forcing the pressure relief valves, open the brass nuts (4) turn hard stb, after several turns, all should be at max stb travel, close the nuts and turn to port, check all sync'd to port end of travel.