[C320-list] Fuel / Water separator

[jpmesa at aol.com]

This is my first boat ( out of 7) with an extra fuel / water separator on it. It's a 1994 Perkins M30 and I have a few questions regarding the filter. The clear bowl on the bottom of the filter has a drainvalve on it. Can I use that valve to clear out a little fuel or is that used onlyfor changing the filter?   If, I can clearout a little fuel does that need to be done with the engine running? Or maybe just the ignition turned on, ( electric fuel pump, etc).  The bowl is niceand clear at the moment, just would like to know ahead of time. 
Thanks,  JOHN    Holokai 2