New Pump Tripping Breaker In House

[mshumack]

The breaker may be weak so it may still need to be changed but I would look elsewhere for a problem.
FYI, you should also check that the wire into the breaker is tight. A loose wire will cause heat build up and increased resistance. You should periodically check all the breaker screws to make sure they're snug - but don't do this with any power on at the breaker.