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  1. #1
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    2008 175 Optimax, problem getting on pad after it gets hot.

    When i first take off , fresh off the trailer, the motor performs perfectly. gets up on the pad quickly, and runs great . 5800 rpm, and runs smooth. I stop at my first spot , fish some, and the motor starts right away, idles well, but has trouble taking off. Everytime I repeat this , It gets worse.

  2. Member Delta Bass Fool's Avatar
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    #2
    Have you checked your primer bulb to see if it is holding a prime when you start to detect the loss of power?
    '94 Charger Foxfire 180VF '96 Suzuki DT150S BASS

  3. Member
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    #3
    would check for spark on all 6 when heated up and mabe cyl drop test to isolate non working cyl, also check for fuel in air side of system
    .................................................. ...the scariest thing in life is the unknown ...................................

  4. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #4
    If you would, please take a moment to review the Announcements at the top of the Forum, and be sure to provide the Required Info with each post. Thanks!


    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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  5. Member
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    #5
    Sorry it took so long to get back with you all.
    SERIAL# 1B308831
    Switched from a 25 Tempest Plus, to a 24 Tempest Plus.
    Did a compression test, 109 to 115 psi.
    Installed new NGK PLUGS. Checked Fuel, and Air Pressure. Both within specs.

  6. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #6
    And what were the Air/Fuel Pressures:

    -At idle
    -Under Acceleration
    -5/10/15 seconds after engine shutdown?

    How is it performing with the 24P Tempest?


    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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  7. Member
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    #7
    the prop did not help much. The engine seems like the spark advance is retarded.
    yesterday I took it below Wheeler Dam. with the livewells full of catfish, and the motor hot from running and heat from the sun. the motor would only turn 3000 rpm. when I tried to take off.

  8. Member lpugh's Avatar
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    #8
    Only one large plug in the tempest for most setups
    Thank You Leon Pugh

  9. Member
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    #9
    yep ^^^^^
    .................................................. ...the scariest thing in life is the unknown ...................................

  10. Member
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    #10
    Could you have a coil breaking down intermittently when hot?
    Praying for a Cure

  11. Member
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    #11
    I did a pressure test numbers were steady at 75, and 85.
    got a wisp of vapor from the air side.
    took all the plugs out, regaped them, and reinstalled them,
    will be putting it in the water tomorrow.

  12. Member
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    #12
    Fuel/air pressures are incorrect and that's assuming you used a proper gauge set - dual glycerin filled set - to measure both at the same time.
    _______

    Phil
    '09 Hewescraft ProV
    '09 150 Optimax


  13. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #13
    Quote Originally Posted by EuropeanAM View Post
    And what were the Air/Fuel Pressures:

    -At idle
    -Under Acceleration
    -5/10/15 seconds after engine shutdown?
    Five (5) separate sets of numbers are needed, see the above from Post# 6. As suggested, you do need a dual-pressure GLYCERIN (or liquid) dampened gauge set.


    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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    #14
    With the problem getting worse, decided to bite the budget bullet, and take it to Jaco's Marine in Lawrenceburg Tenn.
    They promised to fix the beast. Will tell you the problem ASAP.

  15. Member
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    #15
    they will
    .................................................. ...the scariest thing in life is the unknown ...................................

  16. Member
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    #16
    Well it was something I would never found. The Exhaust Tuner had come off. All the studs were broken. Hope to get it back tomorrow.

  17. Mercury 3L/4 Stroke/Verado Moderator EuropeanAM's Avatar
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    #17
    Good catch- that would have been one of the next items to check had we confirmed accurate/good pressures.

    BOLTS are the correct fix (studs will repeatedly come loose... the whole idea of nylock nuts in the exhaust is absurd, IMHO).


    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