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  1. #1
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    Loss of Power 250 PRO XS

    OK. I'm running down the lake yesterday WOT at 74 mph. Then I start feeling a loss of power. The engine is not missing. But my top end speed gradually dropped from 74 to 68. Fished for a while, then took off for the run back to the ramp. Same thing happened again.

    Any idea what might be causing this?


  2. USAF and DOD retired Phoenix Jim's Avatar
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    #2

    Re: Loss of Power 250 PRO XS (matt williams)

    can you say coil!! Welcome to the club.
    2018 Phoenix 920 Pro XP

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

    Re: Loss of Power 250 PRO XS (matt williams)

    Start with a spark test- preferably with the engine warmed up to operating temperature.

    Best means of doing this is on the "Computer Diagnostic System"... have them perform an "Auto Self Test- Plugs OUT of cylinder head" (which also performs a "loaded, 6 cylinder spark test).

    While it's connected, be sure to request a printout of the "Freeze Frame (Fault) History" for future reference (I'd be glad to review this for you if you'd like).



    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).
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  4. Member
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    #4

    Re: Loss of Power 250 PRO XS (EuropeanAM)

    Took it to the shop yesterday. Ran diagnostic and everything checked out OK.

    Then the guy pulled my fuel filter and found some "jelly" like substance in there. He said it was related to the gasoline, but he was somewhat surprised to see it in an engine with just 67 hours. Anyway, he replaced the filter and it solved the problem.

  5. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #5

    Re: Loss of Power 250 PRO XS (matt williams)

    <TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by matt williams &raquo;</TD></TR><TR><TD CLASS="quote">Took it to the shop yesterday. Ran diagnostic and everything checked out OK.

    Then the guy pulled my fuel filter and found some "jelly" like substance in there. He said it was related to the gasoline, but he was somewhat surprised to see it in an engine with just 67 hours. Anyway, he replaced the filter and it solved the problem.
    </TD></TR></TABLE>

    Good deal!

    Not sure how old your engine is, but it might be a VERY wise decision to do the following:

    -Make sure you're running a GOOD QUALITY FUEL STABILIZER
    -Replace the fuel line and primer bulb from the tank, all the way to the engine. The line you WANT will be EPA Complaint... likely gray w/blue letter (not red or rust colored lettering).

    Ethanol enhanced fuel raise "havoc" with any fuel system.... and this is a wise (and small) investment to help give your engine a "fighting chance".



    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

  6. Member
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    #6

    Re: Loss of Power 250 PRO XS (EuropeanAM)

    Thanks for the reply. My engine is a 2008. The mechanic looked at my fuel line (it's grey) and said it is up to specs.

    Do you think this jelly stuff in the filter is something that accumulated there over time, or could it be that it is the result of a single tank of tainted gasoline?

    Either way, I assume the filter did its job and prevented anything bad from getting into the guts of the engine. Is that correct?

  7. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #7

    Re: Loss of Power 250 PRO XS (matt williams)

    <TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by matt williams &raquo;</TD></TR><TR><TD CLASS="quote">Do you think this jelly stuff in the filter is something that accumulated there over time, or could it be that it is the result of a single tank of tainted gasoline?</TD></TR></TABLE>

    Nearly impossible to say, without "seeing" it. I can tell you that today's fuels are degrading 15 days from the time they are pumped, with "gels" forming within 30 days!

    <TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by matt williams &raquo;</TD></TR><TR><TD CLASS="quote">Either way, I assume the filter did its job and prevented anything bad from getting into the guts of the engine. Is that correct?</TD></TR></TABLE>

    That would be "it's job and function".





    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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