If you need to swap a new nozzle into your Mosmatic Nozzle Assembly, see the instructions below for installation. Do the opposite to remove.
1) Clamp 19mm wrench in vise and set nozzle assembly in wrench end.
2) Tighten nozzle with a 13mm socket till tight. NO TAPE.
You could also do this without a bench vise by bracing the 19mm wrench on the bench or ground. Just get it nice and tight. If it leaks, tighten more.