'83 force 55 hp, barely idles w/full throttle

[Luckydog]

motor will start and rough idle w/full throttle and emits heavy gray/white smoke from exhaust. Dies at any other throttle setting lower. Engine does run better when I adjust the screws in, located at the top, above the carb throat(idle mixture screws maybe?) But it still won't idle low enough to engage in gear. The last time we had the boat out a couple of years ago is when it started. Ran great for a few hours, then the motor started running slower and slower. so we headed back to the ramp. by the time we got to the ramp it was barely running and died at the ramp. It seems to be running way to rich. Help!!!

 

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Re: '83 force 55 hp, barely idles w/full throttle

You may have lost compression. A grey/white smoke as opposed to a black/brown smoke indicates water. When you pull the plugs to test compression,examine the plugs,as they'll tell you a lot. A black plug is normal. A black 'tarry' or wet plug indicates oil-fouling, probably burning too rich. Finally, a clean new-looking plug with any amount of hours on it, would indicate a leaking head,exaust port plate gasket(s), or other crack allowing coolant to enter the jug.<br />If you have one or more new-looking plugs, and one or two tarry wet plugs, chances are the tarry wet ones are burning to rich, because they are carrying the entire load.<br />Let us know how the compression test goes.<br />BTW, you are correct..The screw above the carb throat is the fuel/air mixture screw. Also drain the carb bowls,and inspect the fuel tanks for water.