Get the bucket by the well and bail out the boat first. Also, wait until nighttime and go up to the tree blind to get the spare spark plug from the birdwatcher. Now wait until morning to try the boat.

If you open the lid engine you see marks indicating the engine pistons are up to the top left and bottom right, middle (even) in the top right and down (negative) in the lower left.

Set them into those positions with the screw driver, leave to close the lid and then pull the cord. Finally you can go! A map will show you the spots you can boat over to.

Nancy Drew Ghost Dogs Walkthrough