Self-priming surface transfer pump made of bronze construction. Suitable for transferring or transporting clarified liquids such as: must, wine, oil, milk, petroleum, with a viscosity not exceeding four degrees Engler or thirty degrees Centistokes. The liquids to be transferred must be neutral and clear or contain only a small percentage of suspended solids (at most 0.2-0.5%) with hardness and granulometry characteristics such that they do not cause wear on the internal friction surfaces of the pump.