Hotpoint Aquarius t/d motor wont start up unless helped ?

The motor is buzzing but not turning , help it along or give it a nudge (with the covers off ) and the motor will run quite happily until it stops to reverse then wont start again, Is it the Capacitor not giving the motor the initial kick start to get it turning, or is it the motor itself, will just changing the Capacitor cure the problem. the model Number is TDL52P serial number 0769200172