Whisk together the flour and salt in a small bowl.
Whisk together the eggs and sugar in a medium bowl until pale.
Whisk in milk, water, orange juice, vanilla extract, and orange zest.
Whisk in flour mixture until combined. Whisk in cooled melted butter.
If the mixture is too thick, add a tablespoon or two of juice or water.
Whisk until a thin consistency is achieved. Cover and refrigerate batter for 30 minutes.
Heat an 8-inch crepe pan or small skillet over medium heat for about 1 minute.
Cover the surface with a small amount of oil, heat until it gets sizzling hot.
Ladle some batter (1/4 cup or so) into the middle of the crepe pan or skillet.
Immediately start swirling the pan to distribute the batter over the surface.
Cook for 45 to 60 seconds or until light golden brown.
Flip over and cook the other side for 20 seconds.
Remove crepe to a plate and repeat with remaining batter and oil.