Through-Hull Leak (Maybe)

Before I left the boat yesterday, I noticed that some water had collected in the bilge over the weekend's sailing. I checked all of the through-hulls and found that the one from holding tank is (very) slowly weeping water. Last night I taped tissue paper marked with felt-pen around the bottom of ball valve to try and see if the water is coming from the through-hull or the ball valve. The lack of ink-bleeding on the paper today indicates that valve is (probably) fine. This is a bit of a shame since the valve is brand new (was replaced at my haulout in March) and now I wish I'd also replaced the through-hull too. I suspect my yard damaged the through-hull seal when they twisted off the old ball-valve which had become pretty rusty.

Also, unlike the valve, replacing the through-hull involves cutting out a section of the hull and so requires re-hauling the boat. Bah!

There's a chance that the through-hull isn't actually leaking. At least it seems to have stopped today. Its possible that the water is from another source and had just collected around the wooden backing plate of the through-hull while we were healed over while sailing.

Either way, the backing plates look pretty damp and should probably be replaced. I'm also considering temporarily sealing up the through-hull with caulk or 5200 (which wouldn't require a haul-out). I have no immediate use for it since I don't plan on any long coastal trips where it would be legal for me to pump the sewage straight out (and would prefer not to do that in any case, not least because of the stink it makes).