I just got new check valve as pump kept losing prime. After stuggling ti get pump primed i took new valve back out and poured bit of water in it and it dribbled out. Took it back to store amd they said that was a faulty one and gave me another new one. I installed it and have water working for a couple of weeks. Just stopped working again, no prime, wont hold prime. This is the second new check valve it it has a bit of a drip. Is that enough to cause the issue? Why would a check valve go bad so fast?