3 Steps to Fix a Pool Pump That Keeps Losing Prime

Check the pump lid gasket first Nine times out of ten, a lost prime is caused by a worn-out O-ring or a lid that wasn’t tightened evenly. Pop the lid, clean the gasket and sealing surface, lubricate with silicone pool lube, and re-tighten firmly by hand.

Replace a cracked or flattened O-ring If the gasket is cracked or flattened, replace it with a $5 part from any pool store. Keep a spare O-ring in the garage for future use.

Check the skimmer water level and drain plugs If the lid fix doesn’t work, look for low water in the skimmer or loose drain plugs on the pump housing. Low water sucks air, and air breaks the prime.