After being shown how a check valve can break and stick up preventing water flow the proper direction, I was sort of 2nd guessing the replacement of my pump. I asked them if they powered it up after getting it out, no they didn't. Then I started thinking, they did replace 1 check valve. I wondered could that have been the real problem? Did I really need a new pump? I separated the two halves of the pump and powered up the motor. It ran, but it spitted and sputtered going off and on. I shook the pump half, it rattled a lot. I put them together again and powered it up. The pump made a hell of a lot of noise and the motor still sputtered.
Now I feel comfortable that I definitely needed a new pump. I'm glad I told them to leave it here for me to dissect it.