5 Steps to Fix a Skimmer That Keeps Losing Prime

Check the pump lid o-ring first Remove the lid, clean the o-ring and its groove, lubricate with silicone pool lube, and reseat it. If the o-ring is hard or cracked, replace it. This fixes nine out of ten prime loss issues.

Verify the pool water level Make sure the water level is at least halfway up the skimmer mouth. Low water pulls air into the suction side.

Inspect the weir door The flap inside the skimmer should move freely. If it is stuck closed or missing, the pump can pull air instead of water.

Clear the skimmer basket A completely clogged basket starves the pump and lets air in. Empty it and check for debris.

Look for cracks or loose fittings If the o-ring fix fails, check for a hairline crack in the pump housing or a loose union fitting. But start with the lid o-ring.