I am assuming that the photo named "rust" shows the underside of the fitting in the photo titled "drain". That fitting is on the cockpit sole (floor), correct? If so, those fittings are household plumbing fittings. That rusty elbow should be removed along with the drain fitting and replaced with proper fittings and bedded properly. If not, there will be a problem with moisture soaking up in the plywood core with rot and delamination occurring. The valve is a gate valve and should be replaced. Where does the other end go? I assume it exits the boat. Does it do so above or below the waterline. If below, it is important that that pipe, valve, and scupper (drain) fitting be replaced with proper reinforced hose, ball valve, and drain fitting with everything double clamped. It should be done that way if the thruhull is above the waterline but not critically important. For obvious reasons, the boat should be on land when doing the repairs.
Not a hard project, depending upon access of course.
Let us know if you have questions and tell us how you make out.
Tod
Mandolin, Bayfield 36 out of Rock Creek, Chesapeake Bay.
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