Pack a small amount of paper into the knob's shaft hole so that the knob
can't slide onto the shaft too far. Some DG knobs, if allowed to slide all
the way onto the shaft, will hit the panel when you try to adjust the card.
If there isn't enough "throw" before the knob hits the panel, it won't allow
you to adjust the card. The set screw should hold it, but the paper trick
makes it fool proof and relieves the pressure from the set screw.

Jim


"Dave" wrote in message
...
Ummm.. make sure the Knob is not loose and turning freely. We had the
same symptoms, loose knob slipped "in" on the shaft hard against the
panel, so could not push the shaft in to uncage the gyro, so it coud
not be "set". Slid knob back out to proper position on shaft, toghten
set screw, fixed..

Maybe?

Dave


On Mon, 20 Feb 2006 22:33:53 -0600, "mbremer216"
wrote:

Well, it looks like my directional gyro just went belly up. When I went
for
a ride today, the setting knob was very sticky, and then suddenly not
sticky
at all as it now rotates freely and doesn't feel like it is engaging
anything. The gyro card does not rotate with the knob.

I have a Cherokee with a heading tracking Autocontrol III autopilot.

What are opinions regarding having it rebuilt as opposed to replaced?

Thanks

Mike