Jj0plin

We have an old Softub T220 and the impeller broke. I went to a spa store where they gave me one that is a bit thicker (.5 inch) and now the pump shuts off after a minute or less. There are no numbers on the impeller but it measures 7/16 inch, 4.25 and 2 inch for the opening. Sorry I don't know how to describe it more, this is the hubby's area. The pump is a 1hp century bn25v1. Can anyone point me to the correct impeller?