Need Help adjusting idle Mercruiser 140

[Alumarine]

Hi there. The idle is to high on my 1980 Mercruiser 140 serial 5668920.
It varies between 800 and 1000.

I've adjusted what I think is the idle adjust screw. If I back it off AND push on it a bit the idle will drop.
Next time I come back to idle though it will still be too high unless I push on that linkage.

Is it just that it's binding somewhere, or am I doing it wrong?
thanks

 

[Bt Doctur]

disconnect the throttle cable, set the idle speed, adjust throttle cable to fit plus 2 turns tighter ,putting slight pressure to force it against the stop

 

[Alumarine]

Thank you very much.
That's going to help a ton.
I would've messed it up I think.

 

[Alumarine]

disconnect the throttle cable, set the idle speed, adjust throttle cable to fit plus 2 turns tighter ,putting slight pressure to force it against the stop

That worked like a dream, thanks again.