Preheat the oven to 350 degrees F (175 degrees C). Grease and flour three 9x5 inch loaf pans.
In a large bowl, mix together the pumpkin, oil, sugar, and eggs. Combine the flour, baking powder, baking soda, salt, cinnamon, nutmeg, and cloves; stir into the pumpkin mixture until well blended. Divide the batter evenly between the prepared pans.
Bake in preheated oven for 45 minutes to 1 hour. The top of the loaf should spring back when lightly pressed.