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Full Throttle Only Mercury M-800 Thunderbolt Help

M

MyName

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I bought this 1978 Glastron with Mercury 80hp model 800 Thunderbolt 2 stroke 4cyl Ser#500I9751 but soon had running & starting problems. I've replaced/redone all necessary CDI stator trigger rectifier coils starter & solenoid correct plugs wires switch box carb & fuel pump kits fuel lines prime bulb everything! H2o pump ok compression 130#ea But...now at startup the MercControl choke lever must be up and motor runs Only Full Throttle. Putting the lever down does not lower RPM, I can only lower it by hand moving the motor port side vertical Throttle Arm & Spark Arm & go turn off the ignition. There's several adjusting screws, Throttle Actuator Cam, Secondary Pickup and so on?
Question: Can anyone please help? I Called Mercury but they're no help, answering from home eating donuts & my SELOC manual has become like my only source since Sacramento Area Marine Repair shops are forever to busy it seems
Regards,
Stephen
 
You might have slack in the remote throttle system that's not pulling the spark advance back enough.

To clarify: the carbs are closed from about 3,000 rpms and down (in neutral) with spark retard alone taking the idle speed lower. Anything that keeps that lever on the port side from moving all the way to the stop (which might need readjusting) will not allow a lower idle.

Jeff
 
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