I just ran into this problem. I am the first owner of the boat ever to use the holding tank… So tank is half full and I’m getting ready for the NC/SC Govenors cup regatta and think.. ah I will pump out that 100 lbs of weight on starboard.. It not only laughed at me but fell out rolling on the floor… and to this day still wont open..It is siezed shut permanently.. We only stopped trying to get it open when it started to look as if the boat was going to take damage. An easy temp solution is to undo the hose leading to the fitting from underneath and just pull it out of the hatch and pump out directly from it. or if your real brave open main inspection port in the tank and go for shock value… I will be getting new fitting soon and replacing old one.
Didn’t you try the pumpout filler cap before using the tank? I generally like to know if I can empty a tank before I start filling it. Good thing the tank isn’t full, and that you know before it got to past full… with consequent burst hoses.. 😀
Nope I never even thought about it.. Tank was only about half full so no big deal.. just wanted to lighten the boat for the race. It’s a boat!!! got lots of things that always need fixing or projects under way.
Scott