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  1. #1
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    Aug 2016
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    90 4S - which prop

    I want to get a back up prop for my 2016 90 4S, the boat is a Crest in my sig.

    I am not looking for top speed but get down slow to troll and fuel efficiency at plane, that is plenty fast for me.
    Last edited by stockrex; 07-19-2018 at 08:49 AM.
    Shibs
    Crestliner 1700 with 90 hp 4S (2016)
    Avid spoonplugger and student of Buck Perry.
    Fish out of Muskegon Lake, MI

    Onix 10 SI

  2. Member Skeeterbait's Avatar
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    Oct 2011
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    5,796
    #2
    Spitfire X7 4 blade in 17 pitch.


  3. Member
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    Apr 2017
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    Oklahoma
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    #3
    Quote Originally Posted by Skeeterbait View Post
    Spitfire X7 4 blade in 17 pitch.
    Spitfire 4 blade preform much better than a three, no comparison.
    2016 Lowe FS 1710
    2016 Mercury Pro XS 115

  4. Member
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    Aug 2016
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    #4
    Danke, from what I read online most guys added a few miles an hour to their top speed. What happens to speed at idle? now at idle with a 17 pitch prop I can get down to 1.8 to 2.1 mph
    Shibs
    Crestliner 1700 with 90 hp 4S (2016)
    Avid spoonplugger and student of Buck Perry.
    Fish out of Muskegon Lake, MI

    Onix 10 SI

  5. Member Skeeterbait's Avatar
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    Oct 2011
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    #5
    The 4 blade prop should be more efficient at idle because the additional blade and cup it should slip less. That might translate to a little higher idling speed though. It will give you better steering control though.

    Remember on the 4 stroke also, If you do a lot of idling you need to keep a close watch on your oil as most 4 strokes have some fuel bypass the rings into the oil. You may need to change oil more frequently if the level starts to creep up the dip stick.

    While not a cheap option, there is a Mercury Smart Craft engine control gauge called a Merc Monitor. Some of them have a feature called troll control which allows you to set the idle speed on a 4 stroke engine to control forward momentum at idle. Don Weed can give you much more details on that than I though.


  6. Member
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    Aug 2016
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    MI - Michigan - GR
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    #6
    Faster at idle with 4 blade, that makes sense, would a different pitch help slow it down at idle?

    Yes Sir, mine made oil last time I changed oil, I do it myself and often, I use synthetic marine 10w30 and drain every season, did not get to use the boat much till now.

    I have the bluetooth thing to monitor but merc monitor is too expensive for my chunky azz. I rather invest that in a spot lock trolling motor :-)
    Shibs
    Crestliner 1700 with 90 hp 4S (2016)
    Avid spoonplugger and student of Buck Perry.
    Fish out of Muskegon Lake, MI

    Onix 10 SI

  7. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    Apr 2008
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    Greenville, SC (US)
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    94,941
    #7
    Quote Originally Posted by stockrex View Post
    Faster at idle with 4 blade, that makes sense, would a different pitch help slow it down at idle?

    Yes Sir, mine made oil last time I changed oil, I do it myself and often, I use synthetic marine 10w30 and drain every season, did not get to use the boat much till now.

    I have the bluetooth thing to monitor but merc monitor is too expensive for my chunky azz. I rather invest that in a spot lock trolling motor :-)
    Please see the Forum Announcements, and provide the REQUIRED info when posting. Thanks!

    I would not recommend full-synthetic oil (Synthetic BLEND is acceptable, of course). See Engine Owner's Manual for further details on oil selection.


    Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
    Still consider myself a "Marine Apprentice" after 47 years (learn something new every day).
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