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  1. #1

    Default 2003 75hp 75ELPTO fast idle when warm

    Hi all
    So just replaced the plugs and the boat ran like a dream initially then did what it has done since I've owned this engine - started idling higher - don't have a tacho so no numbers but having heard others I'm happy its cold idle is ballpark and its hot idle is 'too fast' (as opposed to ridiculously fast).
    I know its too fast since one warm its slams going into F and even worse in R. Doesn't do this cold. I tried lowering the idle at the global idle screw adjustment but if I go any lower it starts to miss. I also put new fuel and a Nulon carb/engine cleaner thru it wondering if it was some sort of cylinder buildup thing going on but no real change other than giving me a heap of smoke for about five minutes and now less smoke than I was getting before.
    How do I fix this please ? Thanks for taking the time to read this.

    Engine otherwise purrs when cruising and pumps hard at WOT, has an even 120 across the 3 cylinders.

  2. #2
    Join Date
    Sep 2010
    Posts
    22,333

    Default Re: 2003 75hp 75ELPTO fast idle when warm

    Is the throttle arm on the motor against the idle stop.----If not ,then you need to adjust the cable at the motor so it goes against the stop with a slight preload.

  3. #3
    Join Date
    Sep 2003
    Location
    New Tripoli, PA, USA!
    Posts
    17,180

    Default Re: 2003 75hp 75ELPTO fast idle when warm

    Idle speed is determined by the spark advance, not the carbs.

    Look for an adjustment there and back it off a bit.

    Jeff

  4. #4

    Default Re: 2003 75hp 75ELPTO fast idle when warm

    Quote Originally Posted by fastjeff View Post
    Idle speed is determined by the spark advance, not the carbs.

    Look for an adjustment there and back it off a bit.

    Jeff

    Thanks very much for you help

  5. #5

    Default Re: 2003 75hp 75ELPTO fast idle when warm

    I will check this thankyou

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