Why Won’t My Pump Prime?

You could have a leak in your suction line, generally the fitting underneath the skimmer.  Usually, if the system is running fairly well and then you begin having problems when you are vacuuming, this would usually indicate that you have a cracked fitting underground.

If it just won’t prime when you go to turn it on and it was running fine before, this would suggest that the strainer lid may not be tight enough or the gasket under the lid is stretched or pinched.