Jim is right here bad batteries won’t smoke it may be the brushes, Why don't you try changing the batteries and that will give you the confirmation o whether batteries are the real problem or brushes. I have recently come across the batteries for your model here http://amzn.to/2hIhkbD
I am also sharing a 20% OFF code for you ( FP3YYHB3 ) If you want to buy the batteries.
I am new here and excited to help everyone as much as possible preferably for woodworking tools.
As an Seatle resident and associate at Parkland Woodworking, I have the privilege of meeting a lot of woodworker professional alike, who are making wonderful things. I’m pleased to introduce myself to Tools in Action.