Lionel O Gauge Milwaukee Road Electric Locomotive 6-8558.  I tested this locomotive and the center gear came out. I put it back in place and reattached the truck cover.  It has broken off, I JB Welded it back.  I took it apart because the rear light was not working.  The wire is loose and will need to be reattached.  Please see pictures.  

Shipping is $18.85 with tracking.  Thanks for looking.