Getting under it
Hi Hans -See how much access you have between the cockpit and the hull below the drain. You should have a hose clamp under the drain; check to see if the leak if at that connection. To remove the actual drain, you should be able to remove the caulk with a razor knife &/or some solvent to break it free. Rebed and re-attach hose with clamp, then test for leaks.Let us know how what you find.Best,Trevor