Dave: My bad. I am calling the screw to the regulator an idle adjustment screw. I stand corrected. It is the regulator screw. As of yesterday I did install new gaskets and O rings. The regulator plunger is ok. looks new. Unfortunatly, I am still getting the same results. It must be something simple that I am missing. It usually is. I still haven't figured out why the engine will run full bore with the mixture control closed !!!!!!!!!!!!!!!!!!!!!!