"Peggie Hall" wrote tank by pumping the head.

You--and most other boat owners too--need to learn to use the "dry"
mode

It does work and I use a variation of this method. The variation is
only because our Groco, at least, requires more wet strokes to move
paper to the bottom As soon as stuff is out of sight, I switch to
dry.

At the end of any weekend trip or day sail with lots of guests, I do a
long wet flush from empty to be sure the line is clear.

In view of the difficulty most guests have with the regular method,
even with printed instructions, I think I'll just put up with more
frequent trips to the pump out instead of trying to add another lever
sequence.

BTW tightening up that hose clamp has brought the water off pump
cycling of my fresh water pressure set down to only about once every
2 -3 hours. I can't fix the last little drip until I move the pump so
I can get at a metal joint on the tank that is weeping slightly but
it's quite livable. I'll do that when I install the accumulator tank
I bought yesterday.

--

Roger Long