I worked out that the probelm lay with the rack and pinion alignment.
Although the tape mechanism was fully down, the rack needed to advance
one more tooth to allow take up mechanism to start operation. After
marking the rack and pinion in both the up and down position(in case
things went badly wrong!), I was able to advance the rack one tooth by
loosening the (2?) screws that hold the plastic side to the metal
base. Trial and error really, but one tooth enabled a successful 'hand
wind' loading operation. I couldn't see any significant damage to the
(metal) rack or pinion, but time will tell whether this reoccurs.

I think the misalignment probably occured when I first reassembled the
unit after replacing the load motor. The trick seems to be to make
sure that the tape basket is pulled back to the fully ejected
position, together with the underside mech when the load motor is
replaced. In my case, I don't think it was quite there so the mech
unloaded 1 step further than it should (the initial whirr, and
probably click, that I heard).

I found an electrical schematic for the NV-HD650, which wasn't much
use, what I really wanted was a mechanical schematic.

For info, I got the spare motor with drive bush from seme.co.uk. who
were quite helpful and quick, but not online ordering.

Ian

"Peter Lord" wrote in message ...
I had a similar problem on a NV HD680B - fault was two teeth stripped on the
loading arm gear only visible when the mech was out. The 680b is fitted with
a Z-Mech which I am currently attempting to buy a manual for. VCR gave
fault code F06 in my case.

I have a copy of the NV-HD650 schematic if you would like one.

Regards

Peter

"IanG" wrote in message
m...
I've just replaced a split loading motor drive bush on my Panasonic
NV-HD650 VCR (with K-mechanism). As far as I can see, there should be
no need to readjust the mechanism as I didn't disturb anything apart
from the motor, but on reassembly, there was a brief whirr of the
motor, then nothing. No fault codes and a when a video is pushed into
the slot, there is no attempt to pick it up.

I have decoded, I think, the phase diagram on the underside of the
case, and see that this refers to a tape in the loaded condition. My
problem is that I can hand wind the mechanism to the point where the
tape is in the lower position, but then it stops. At this point, the
metal pinion has reached the end of the rack and looks like it should
stop revolving when the main cam continues to turn. All looks OK so
far, but I cannot get the main cam to turn further and move the tape
loading arms. It looks like, if I could get it to wind a bit further,
that all the marks would be in alignment, so I am reluctant to start
dismantling further.

Does anyone know what might be stopping the mech at this point?

Thanks for any help