Preheat the oven to 350 degrees F (175 degrees C). Grease a 9x5-inch loaf pan.
Combine coconut oil, eggs, and vanilla extract in a large bowl; whisk well to combine. Add flour, sugar, baking soda, cinnamon, and salt. Stir well until combined. Fold in bananas, pineapple, and coconut; stir until just blended. Pour batter evenly into the prepared pan.
Bake in the preheated oven until a toothpick inserted into the center comes out clean, about 1 hour. Cool in the pan for 10 minutes. Remove to a wire rack to cool completely.