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  1. #1
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    250xb water pressure

    water pressure runs around 17 to 18 at wot and about 3psig at idle with a strong pee stream however at the lake over the weekend after taking off from first stop the pressure would only go up to 9 or 10psig, idle pressure also low and pee stream did not appear to be as strong. could something have gotten clogged or some type restriction i can checkout. THANKS....

  2. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #2

    Re: 250xb water pressure (stratospro)

    Need a couple of pieces of information prior to commenting:

    1. Does your gearcase have LOW WATER PICKUPS in the nose of the gearcase?

    2. WHEN was your water pump last replaced?



    Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
    Still consider myself a "Marine Apprentice" after 48 years (learn something new every day).
    Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor

  3. Member
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    #3

    Re: 250xb water pressure (EuropeanAM)

    yes it has low water pickup,and new impeller about 8 months old

  4. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #4

    Re: 250xb water pressure (stratospro)

    I would recommend removing the gearcase (plan to replace at least the impeller and gaskets, at a minimum).

    Remove the plate below the impeller- and the shift-shaft seal carrier.

    Inspect the passages between the LOW WATER PICKUPS and the WATER PUMP for wood, debris, or various forms of "organic matter".

    More than likely, you have something floating around in there that's blocking off the low water pickup water flow (leaving only the water flowing from the side pickups).



    Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
    Still consider myself a "Marine Apprentice" after 48 years (learn something new every day).
    Mercury Parts, Mercury Outboards, Smartcraft & Accessories, Injector Service, TDR Reeds- BBC Sponsor

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