Self priming pumps are able to pull prime after loosing prime or in some cases can run dry and initiate priming. Centrifugal pumps which SOME are called self-priming actually need to be primed the very first time and then after should hold prime or start up again if pump has retained its priming liquid in its volute. These pumps do not prime from a dry condition.

The second type of Self Priming pump is a positive displacement one and can pull prime completely on its own from often a dry condition. These would be diaphragm / mud Pumps.

Self-priming pumps all have a common limit to how high they can lift or prime. This is often 25 feet maximum and with some pumps may take up to 5 minutes. While some are limited to only a few feet vertical suction lift.

Self Prime pumps come in all materials like Cast Iron, FRP, Aluminum and Stainless. Powered by electric motors, gas / diesel engines, PTO / pedestal and air / pneumatic.

Many self priming pumps are able to handle debris / trash / solids, while others are for high pressure (fire fighting, irrigation, washdown).