[Mrmerlin]

have you checked the fuses?
then have you checked the pull switch?

NOTE the pull switch has a small non electric washer on its tip,
that can sometimes shatter and thus short out the switch,
as soon as its pulled the fuse blows.
If the fuses are good then the motor only runs when the knob is pulled then the motor need a 2 new transistors intalled this will fix the motor,
Their is a writeup on RL about the PN of the elex components required

To remove the motor from the attach point first remove the small aluminum cover,
Mark the position then loosen the 2 10mm bolts that hold the motor gently pry the link arm off the top portion of the lower latch drop the motor down then unplug the oval connector from the motor body