Long time lurker, first time poster. I just recently backwashed my pool and my pump is now leaking like a sieve from underneath. For the record, I replaced the shaft seal and impeller (because the plastic threads were cracked) less than a year ago because I was having leaking issues and haven't had any issues since the replacement. I can't imagine that it's common for shaft seals to go bad that quickly, is that accurate? Also, is it possible for the water to be leaking from between the pump housing and the seal plate? I can't remember what shape the diffuser gasket was in when I took it apart last time, but I'm guessing that could lead to leaking? Also, just as another data point, I've had leaking issues in the past to the point where my motor housing had rusted underneath and I had to replace the motor bearing. Not sure if shaft warping is a possibility, but just thought I'd throw it in there to be thorough.
Thanks in advance for any help you guys can provide.