Drain cocks come in several different styles--screw threads, quarter-turn twist, and quarter turn and pull.
Then, close the
drain cock. Handle the drained fuel as hazardous waste and recycle it as prescribed by your SOP.
Open the separator, located behind the engine access door (curbside), by turning its
drain cock counterclockwise.
If that happens, fuel pours out of the
drain cock all over you and the ground.
* If the fuel is free of contaminants and water, close the
drain cock. Your system is not contaminated.