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  1. #1
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    Default 1983 7.5 hp mercury carb to throttle linkage

    Hi.i Need some help with with this motor.sn is 6240895.after water pump change I started the motor and idle is pretty high.noticed that there is no linkage between carburetor and throttle,only choke is hooked up to butterfly, and it stays wide open when advancing the spark/trigger lever.is this normal that carb butterfly stays in one(open) position at all times?.also....what is tune up procedure?i just acquired this engine and any help would be nice.thanx

  2. #2
    Lieutenant Commander
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    Default Re: 1983 7.5 hp mercury carb to throttle linkage

    There should be linkage from the throtal to the carb and a cable from the choke nob to the shutter in the throat of the carb. A picture of the carb would help. PO might have had the carb off the motor and did not replace it as it should be or lost some of the linkage. The shutter in the throat of the carb is for the choke and should open and close when the nob is moved.
    JMO
    Oldman570

  3. #3
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    Default Re: 1983 7.5 hp mercury carb to throttle linkage

    her is some pics018.jpg014.jpg015.jpg016.jpg.
    i see.there is two shutters in that carb.one for choke and one for throttle.did not see the one further inside the carb.is there a special procedure for link and sync on this engine.i tried to adjust carb idle for lover revs with no result.its still reving too high.thanx

  4. #4
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    Default Re: 1983 7.5 hp mercury carb to throttle linkage

    The idle has to be set with the motor in a barrel of water or in water with the motor in FWD gear. It has to have that backpressure to be set correcly. The RPM's should be set at 650 to 700 RPM and the idle jets should be set at 1 1/2 turns out from lightly seated and adjusted alittle rich from best idle. The adjusting screw for the idle is on the lever of the linkage above the cables with the set lock nuts, from the way it looks to me, to set the idle at the recommended RPM as the idle jet is being set. JMO
    Oldman570

  5. #5
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    Default Re: 1983 7.5 hp mercury carb to throttle linkage

    Ok.will do that.thanx.

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