1978 35 HP Johnson. Carb needle is vibrating to the lean setting

[antzboat]

My carb needle (or carb knob, not sure whats it called) is vibrating and turning to the lean setting which causes the motor to sneeze and eventually stall because its It is running too lean. If I gently hold my finger on the knob it will not move and the motor runs perfect, also if I drive slow it will not turn, but once i get up to speed it starts to vibrate and spin towards lean. Is there anything I can do to fix or replace this part? And is the carb needed the correct name for this piece?

I attached an image of the area I am talking about under this posting, its has written on it to turn one way for lean and one way for rich.

 

[antzboat]

Motor image

 

[dazk14]

What kind of shape is the rubber retainer, it's normally a tight fit and only a few bucks.

Moly grease (the heavy dark stuff) can be used on the threads to firm it up.

Keep the grease off the needle end.

 

[antzboat]

Thanks for the info ill check that grease out. As just a very temporary fix. Can I put some electrical tape around the knob to stop it from vibrating, or is that possibly dangerous?