Altimatic II B Roll problem

[Donald Moreau]

I just recently purchased a Twin Co with altimatic II B, and when you turn the roll on it won't work. The altitude hold works, but if I turn the roll switch on, I can hear the servo but it doesn't turn the yoke. It has the rectangular box servo on the firewall. Hopefully I can adjust the clutch in the servo. Before I started taking anything apart I was wondering if anybody has done this before? And if anybody has any input it would be greatly appreciated.

[md11flyer]

Sometimes its a matter of lack of use . Sounds like the servo soleniod is not doing its job. There are 2 reasons it doesn't work properly.. one is its gummed up with dirt and oil, second is the ground to the solenoid is compromised by either the 40 year old "grey wires" or connectors. You could check the solenoid / servo by swapping it out with a known good servo. If the good servo also gives the same symptoms, then you have a cable / coonector problem, if the new servo works well then you now know the servo/solenoid needs overhaul.
Have you had avionic work lately? Sometimes when you muck with the grey cables connecting the autopilot components, some of the 40+ year old wires and the connectors fail. I have personally have had. the same problem with the grey wire symptoms after a panel upgrade. The rerouting of these old wires caused a ground wire to separate from the connector to the ADI,
causing various problems that were only solved after ohmning the grey wires to the ADI.
I hope this helps,
God luck
Gary

[steen]

Donald,
I would bet that the clutch has been overeridden and disconnected by manually countering the autopilot with control inputs.
This requires a mechanical re-connect at the servo.
The other possibility is a corroded box under the #3 pass. seat floorboard that, when cleaned up, performs remarkably....like new!
Good luck. It's a great autopilot.....years ahead of it's time.
Steen