My circulator pump crapped out and I tried replacing the impeller, but that wasn't it. I can hear light buzzing from the pump, but nothing circulates. I have a Taco 006-BC4, but I found a Taco 006-B4 that someone is selling. I only want to replace the pump motor and not the connection, and as far as I can tell, the motors between the two are the same and the difference in the models is only the connections. All the electrical specs appear to be the same. Does anyone see it differently? Thanks. http://www.taco-hvac.com/uploads/Fil...ry/100-1.7.pdf