Without more info it's hard to say. This could be something as simple as a dirty lid "o" ring, if it is streched out or cracked you will need a new one. If not you can clean with dish soap then when you relube "o" ring use teflon or silicone grease then wipe excess off as this excess will collect dirt, also clean lip of pump pot also. If this is not the problem then you may need to replumb pump or replace seal. When you loose prime if the pump runs for any lenigth of time the water left in pot will overheat and cause plumbing to warp or seal falure.
Answers & Comments
Without more info it's hard to say. This could be something as simple as a dirty lid "o" ring, if it is streched out or cracked you will need a new one. If not you can clean with dish soap then when you relube "o" ring use teflon or silicone grease then wipe excess off as this excess will collect dirt, also clean lip of pump pot also. If this is not the problem then you may need to replumb pump or replace seal. When you loose prime if the pump runs for any lenigth of time the water left in pot will overheat and cause plumbing to warp or seal falure.