Pumpout deck cap stuck

[Island Time O25]

While replacing the deck cap I would seriously consider replacing the waste hose as well. And may be the waste tank also. IMO the stuck cap is indicative of the general level of maintenance (or lack thereof) for the waste system.

[wsmurdoch]

My boat has been routinely pumped out using a nozzle with a rubber stopper like thing on it that would fit into any size waste fitting. The stopper like thing sealed at the top lip of the waste fitting. The threads below were left filled with s**t and toilet paper residue which dried in the threads and glued the screw cap in place. The cap was so hard to turn that I was scared that the deck fitting would go around before the cap would screw out. Once the cap was out, a wire brush and water cleaned the threads which I then greased. I'm hoping that a quick rinse with a hose after a pumpout will prevent a recurrence.