I have a year old Minn Kota 101 Maxxum. The prop will spin at all speeds when it is out of the water. When it gets water resistance it will not spin and loses power.

Could this be a battery problem??? My batteries are dated 12/05.

Pull the prop and see if the dowl pin has sheared. That's what it sounds like.

I checked the pin first and its ok. After the TM has water resistance, and pulled back up it will spin for a few seconds and then stop. You can hear a buzz in the lower unit.  

However, after a few min. it will spin at full speed, while out of the water.  Back in the water, it loses power.