Firing up the pond at the building I manage part time. Filled the pond completely up. Did everything I could to bleed the air out of the lines. Turned the power on to the recirculating pump and it whirred for about 30 seconds then died. Dead silent. Power is good to it. Before I order a new one and replace anybody want to give me some troubleshooting thoughts? I put my wrench to the propeller shaft and it turns.