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Freshwater to Salt water...

Discussion in 'Engines' started by ShearPleasure, Mar 15, 2022.

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  1. Hi, moving a 44' Viking with 6-71 DD that has been freshwater her whole life and now will be taken to florida. Suggestions on what I need to do to the boat and the motors to make this transfer. Maintenance difference from Fresh to salt? Thanks!
  2. Capt Ralph

    Capt Ralph Senior Member

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    Bottom paint and zincs are different.
    Fresh water zincs are usually a lighter aluminum, salt water zincs are a mixture of different monkey metals.
    Also the engine zincs.
    Fresh water bottom paint usually does not have copper or most of the poisons that salt water bottom paint has.

    Your boat may actually run a micro bit faster. As the more dense salt water helps your ship float a micro inch higher and offers a micro ounce more thrust on the propeller face.

    All else should be the same.
  3. YachtForums

    YachtForums Administrator

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    In the performance boat spectrum, the difference in top speed can be several MPH as you approach or exceed the triple digit mark in saline solution.
    cleanslate likes this.
  4. Ken Bracewell

    Ken Bracewell Senior Member

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    I suspect you don't have a Reverese Osmosis water maker, but they need to run at a higher pressure in salt water than when in fresh.
  5. mapism

    mapism Senior Member

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    Yeah, but on a DD powered 44' Viking, I'd expect the "micro bit faster" estimated by CR to be closer to the reality... :D

    Back to the OP question, I can't think of anything else on top of what was already mentioned.
    But since you asked also about maintenance, you might consider fitting some connections for fresh water flushing of any raw-water feeded onboard equipment (typically, engines, genset, airco).
    The logic being that whenever you leave the boat unused for some time, it's better to have fresh rather than salt water in contact with any metal bit.
    A problem that you didn't have during the "previous" boat life in freshwater, obviously.
    As an example, I explained my own flushing system in post #40 of this thread, but there are also other possible ways to tackle this problem.
    Including doing nothing, in fairness - the large majority of salt water boats are NOT equipped with any flushing system, and it's not like all of them corrode overnight...
  6. cleanslate

    cleanslate Senior Member

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    Whaaat ?!? Lol.
    Definitely does not have a water maker.
    Unless you consider a leaking rudderpost or stuffing box to be a water maker?
    Lol.
    Not saying that the gentleman has one.
  7. cleanslate

    cleanslate Senior Member

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    Really have to keep up on your zincs more.
    Time to buy some “real” bottom paint and put that on. That can be done when you arrive in Florida.
    Uhm , well , basically you have to double up on the maintenance .
    Anyway, enjoy! Mind over matter.
  8. Capt Ralph

    Capt Ralph Senior Member

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    Josie just reminded me, Cover your varnish or any fine wood.
    The sun eats everything down here way different than up north, then throw in some salt under some sole or heel (ouch)..