96 850T starting problem

My 96 850 T has 245000 miles. When cold it starts fine however if driven a short distance 1/4 - 1/2 mile and shut off it sometimes wont start. When the ignition is turned to start it only makes a faint clicking sound, the starter doesn't spin. After 10 or 15 minutes it again starts fine. If driven more than a few miles after a cold start everything works fine. My initial feeling is that the starter brushes are worn and sticking. Any help in diagnosing this odd problem will be appreciated. Thanks John