Autopilot Servo

[Paul Sharp]

Well, this morning I turned the A/P on and I hear the servo motor going, so I took off that inspection panel and looked at it. I couldn't read the model or part number plate because it was too close against a panel and impossible to read in the small space wihtout removing the unit.

Whenever the A/P is on, the motor is running - still trying to command a left turn, I suspect as that's what it does when I'm in the air flying. It doesn't matter whether the knob is in or out or what any other knob positions or settings are, it stays running trying to make that turn.

The case was split diagonally, held in with 4 screws so far as I could tell. The whole unit, i.e. the whole case, was mounted in the wing, of course, but if I were to try to undo the "electronics" portion, or what appears to be the outer hal fo the split case, I'm not sure what I would have found and I was leery of messing with that if it might leave the plane where I couldn't fly it while getting it checked or fixed.

So I'm not sure what to do next at this point.

BTW, Bob, when you mentioned "so that the heading bug aligns with top dead centre" what do you mean? Do you mean that when you set a course with the A/P "Heading" knob that the bug on the DG should center (or else you adjust it then with the little outer lever)?