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  1. #1
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    Mercury 250 XS 4 Stroke (total RPM?)

    For a 250 PRO XS 4S (2b781054)

    I see the RPM range is 5600 to 6200 RPM

    The current RPM I'm getting is around 5750 with a super light load. I have a 26 FURY 3 blade on it now, but the hole shot is lacking on boat, so I think I'm a bit over propped, so I'm going to come down in size.

    I really want to go with a four blade prop, since I want a better hole shot and mid range cruise.

    Do you think I should go with a 24 or 25 Fury 4?

    Also, should you be right at the 6200 top RPM range or is anything in the 5600 to 6200 RPM range fine at WOT?

  2. Member low slung cruiser's Avatar
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    #2
    Yes yes and yes...
    id suggest a 24p 4blade fury...
    get as close as you can to 6200
    Sterling 22XS / Mercury Pro XS V8

  3. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #3
    Definitely way over-propped. What boat is this engine on?


    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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  4. Member
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    #4
    Quote Originally Posted by EuropeanAM View Post
    Definitely way over-propped. What boat is this engine on?

    It is on a 20' pad custom aluminum bass boat. Built something like an Xpress, but with heavier gauge aluminum. I took it out again with three big guys and light gear and 15 gallons of fuel I was only getting 5625 RPM. You think I should go with a 23 or 24 fury? I was wanting a four blade fury, since holeshot is taking about 8-9 seconds to get on plane, but I've read they aren't good for power loading and with our steep ramps I sometime have to power load to get as close to the front roller as possible.

    Should I gain about 200 RPMS for every pitch down?

    Don, in this cooler weather and lighter load with two guys what total RPM should I be trying to hit?

  5. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #5
    I would try a 23P, personally. I would also be having the "Demand Linear" verified on the G3 Computer Diagnostic System (confirming it reaches 100%) BEFORE I bought any props.

    Holeshot will improve considerably as you get the engine up into the target RPM range. Really should be up there in the 6100-6150 range.


    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).
    Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor