Seacock maintenance?

[Hillbillybuddha]

The thru-hull seacock for my head waste overboard is not closing all the way. There's only the smallest, slow leak so I'm not worried about it. Also there's a hose attached that goes above the waterline to the y-valve that rarely is open to overboard. I wouldn't have even noticed the seacock leak if I hadn't removed the hose to change it to a low odor hose. I'll replace the seacock next time I haul out which will be next year (knock on wood) when it's time for paint.

My question is, there any maintenance I can do on it until then? I open and close all my seacocks monthly, just to make sure they don't freeze up, but other than that.