I need to replace the shaft tube and bearings on my Maxxum 74. I heated the shaft connection and unscrewed the tube. When I slid the tube up and off, the 3 wires (red, black, and another black) were exposed. One of the black wires was unplugged from the motor housing. The red wire and the other black wire (has a 3 pin connection for the control box hook up) were hooked up into the motor. Did the 2nd black wire come unplugged accidentally or is it not supposed to be connected? I don't know the serial number because it's not under the foot control where I read it should be. Any ideas about this wire? It's a variable speed if that makes any difference.