Dryer won't start - Kenmore 110.88752790 stacked unit

[aribert]

24inch wide "Kenmore" stacked unit.  Model # 110.88752790   When start button is pushed, frequently nothing happens.   Sometimes when the start button is pushed there is a buzzing sound for approx 5 sec (and the drum tries to turn - slowly creeps) and then shuts off.   With one hand on drum switch and the other pushing in the door switch, I was unable to assist in spin starting the drum with my missing 3rd hand.   It appears to me that there may be two issues - the start button and the motor for the drum.  The drum appear to rotate freely - subjective.  The drum motor does not have a capacitor start like a typical fractional hp motor - correct?  

How do I proceed to trouble shoot and repair?