Cold weather, bout 15-20 degrees out, Power.

Cold weather, bout 15-20 degrees out, Power Steering return line cracked, replaced line with same size hose 3/8" power steering on my van, started it up and turned wheel back and forth to get air out, had a small leak didn't tighten clamp enough, tightened clamp, worked fine until I backed up and started going down the road, heard a pop and no power steering again. Return line looks fine, leak was coming somewhere from around the pump area, did I blow the pump again? Second time I have changed pump within year and a half, what am I doing wrong?