Got a question that I'm hoping this forum can help with. I've read everywhere on my problem and am just not finding anything that matches my specific issue.

My old booster pump (Polaris PB4-60) started making really loud noises so I bought a new one and installed it. When I started the new pump up, it's making noises very similar to the old one. I took the whole thing apart again to make sure I didn't have anything in the intake line hiding somewhere and I did not find anything.

Water is definitely getting to the pump and through it. When the pump first starts, it runs quietly but after about 30 seconds to a minute in, it just starts making the loud noise again and continues for as long as the pump runs. Since it's brand new, I strongly doubt it's the bearings. Similar, the volute should be in good shape also as it's new. Any ideas on what could be causing the noise?

If you need additional info, pictures, etc. just let me know.

Thanks.