These parts are not threaded. Use some type of penetrating oil. Let it set until it spins pretty easily. Then with a pair of pliers' gently pull and twist it at the same time. If you plan on reusing the fittings, be sure not to damage them with the pliers when you are extracting them. When you are ready to reinstall just lightly sand dowen the fittings where they go back into the hole, use some gasket maker to insure no vacume leaks. Insure you clean the holes out well so the gasket maker will stick. Hope this helps. It worked for me.