Autopilot Servo

[Paul Sharp]

re: 1967 T337B, w/Cessna Navomatic 300 single-axis autopilot -

It has always worked fairly well in heading mode - a little looser in trackng under the "Nav" mode, but worked OK.

But on last trip, autopilot started commanding left turn. Nothing I did would change the settings. Worked that way in either the DG or Nav modes, no matter where the heading knob was turned.

Called Autopilot Central in Tulsa. They said it was most likely to be the servo unit, which if I remember right he said was in the right wing, accessible via an inspection plate between the flap and aileron.

If it turns out to be bad then they charge $895 to overhaul the servo.

Any suggetions from others out there?

1 - Is it hard to remove and reinstall the servo?
2 - Would it be cheaper to buy a surplus servo?
3 - Other places to recommend that do good work for less?

Thanks.