Thanks to great advice from mas985, I recently replaced a couple pump motors/impellers.
One was the recirc pump, that went great, no problems.
The second was a pump used for spa jets. It is a Whisperflo WFE-6 on a 2.20 SHP Emerson pump (correctly sized impeller/pump combo).
When the spa-jet pump started up, it sounded just fine, nice and quiet/smooth. That lasted for about 20 minutes or so. The next time I walked by the pump, it was loud. The best way I can describe the sound is like loud "static". Crackley, noisey. But the funny thing is that it does not sound like it's coming from the new motor that I replaced.
It sounds like it may be coming from the pump head itself, close to the motor.
When I had replaced the motor, I replaced the seals and gaskets as well. Could it be that one of those seals is bad somehow?
Thank you in advance for any ideas!