On 22/06/2019 10:48, Chris Hogg wrote:
On Sat, 22 Jun 2019 02:27:06 -0700 (PDT), wrote:

Thanks for all the comments so far.

Its a GL701, so may well be belt and shaft drive like the GL7xx models mentioned.

Yes, the motor's in the handle on that one. Diagram here
https://tinyurl.com/y6679fwe

Short of dismantling it, I don't see how you'll tell which part of the
drive sequence has failed. I suppose if you could work out whether the
flexible drive is rotating by it's sound or vibration, in which case
the failure is down in the head. OTOH if you can't feel vibration or
hear it rotating, it may not mean that the failure is at the top end -
it may just be that the drive shaft turns quietly! If you strip it
down, take lots of pictures as you go. Helps no end with reassembly.

I'd probably start at the bottom end. You might find a failure on the
last bit of flexible, you ought to be able to unthread the flexible from
that point. The top end should be pressed into a square section to
provide drive. If you just find twisted wire at the top then it has
failed at that end, you will need to dismantle the top to retrieve the
second bit.

Pretty obvious once you get it apart.