To complete the San Cordoba tomb in Cenotes in Shadow of the Tomb Raider push the cart out of the way of the canon. Push the canon down to clear the path. Kick the raft into the water and use it to climb up the ship. Use the lever to move the canon above the weak planks. Jump into the water and swim to the front of the ship and climb up. Go over to the side of the ship and jump across to the cliff. Make your way around and jump back over to the ship and free the mast using the crank. Climb the mast and make your way back to the cliff. Climb around and get back to the middle of the ship and drop down.
Use the lever to move the mast so that the beam points towards the box. Go around the mast and climb on a box and jump to the beam. Climb over to the box, jump across to the front mast and climb up the mast. Use a rope arrow to make a path to the front of the ship, use the crank to release the canon and go down the rope. Drop down into the captain’s cabin to complete the San Cordoba tomb.
As found on Youtube