Hull Patching is part of a Ship Repair mini-game that pirates can play to fix their vessel at sea or to earn some pocket money repairing vessels at the tables stationed around each Shipwright stand. These tables are marked with signs, indicating the difficulty of the repairs needed.
At sea, simply walk to a part of your ship that has a hole in the deck and press Shift. When sailing, the difficulty will vary depending on how damaged your ship is.
Play Hull Patching
This messy challenge involves slapping tar onto a leaking hull. Using the mouse, move the bucket and targeter to a spouting leak, then left-click to throw tar on it.
If you hit, the tar will stick and the hole is plugged. If not, try again. New leaks will continue to appear until you have plugged them all.
This event is also timed, so try to work accurately, but quickly.