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  1. #1
    Cadet
    Join Date
    Jul 2007
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    11

    Default 4.3 cobra loss of power

    Negotiating several problems with the 4.3 cobra. With this one the engine wants to die when on plane above 300 rpm. I can throttle back/or to neutral and the engine kicks back to life. It sometimes dies completely and I can restart fine. Its got me puzzled. I have checked vent hose. fuel return hose from carb, fuel water separator and fuel line connections. I drained and completely dried the fuel tank(built in tank) last year and check for debris and h20 and found nothing.

  2. #2
    Honorary Moderator Emeritus Don S's Avatar
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    Aug 2004
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    Default Re: 4.3 cobra loss of power

    Sounds like carb issues. May be time for a rebuild.
    Don S.


    Please, no PM's (Private Messages) regarding boat/engine problems.
    That is what the forums are for.
    Only forum/moderator issues will be answered in PM's.

  3. #3
    Petty Officer 2nd Class
    Join Date
    Apr 2011
    Location
    Omaha, NE.
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    185

    Default Re: 4.3 cobra loss of power

    My 4.3 did this and it was the fuel filter. Appears you looked into that. Is the fuel pump pressure where it shouold be?

  4. #4
    Cadet
    Join Date
    Jul 2007
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    11

    Default Re: 4.3 cobra loss of power

    Got the carb kit today. Mine does not have a filter that I can see. not one inline or at the fuel pump, just the fuel water separator and of course the carb fuel inlet filter. How do you check the fuel pump pressure ?

  5. #5
    Honorary Moderator Emeritus Don S's Avatar
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    Default Re: 4.3 cobra loss of power

    Mine does not have a filter that I can see. not one inline or at the fuel pump, just the fuel water separator and of course the carb fuel inlet filter.
    That IS a fuel filter, not just a water separator. Probably why it's called a water separating fuel filter. It needs to be replaced yearly and the contents of the old filter checked for water.
    Don S.


    Please, no PM's (Private Messages) regarding boat/engine problems.
    That is what the forums are for.
    Only forum/moderator issues will be answered in PM's.

  6. #6
    Cadet
    Join Date
    Jul 2007
    Posts
    11

    Default Re: 4.3 cobra loss of power

    Don- I thought that was the only filter I need, but wanted to double check with you all. Dumped it the other day into a glass jar, no water present. Last year when I changed the filter, when it settled I has an inch of water.

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