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  1. #1
    Join Date
    Jun 2003
    Orlando, FL

    Default 1973 25hp Johnson rough idle after warm

    When the engine is just started, it runs great at all speeds. However, when it warms up, after about 15 mins of running, it will not idle. It idles on 1 cylinder then eventually stalls. In addition to start it I have to start it in gear at 1/4 throttle setting. It has new points, condensors, plugs, carb rebuilt, compression at 120 plus, rebuild in last 20 hrs. Help!

  2. #2
    Lieutenant Commander
    Join Date
    Mar 2001
    Stockholm, Sweden

    Default Re: 1973 25hp Johnson rough idle after warm

    The ignition coil I guess. Can you switch them and see if the problem moves to the other spark plug?

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