Hello!
I am posting this here as the result of a suggestion on
rec.boats.cruising

I am currently singlehanding down the east coast, and have run into a
problem with my autohelm 4000. When in the disengaged position, the
belt still ratchets over the drive gear (catches on the teeth, doesn't
disengage properly) and interferes with free (hand steering) operation.
As long as it is engaged it seems to work normally.

I would suspect the belt tension being too tight, so that it doesn't
release completely, but I haven't heard of too many belts tightening as
opposed to loosening over time, although I guess anything can happen.

I have had the wheel actuator apart, the idler wheel actuated by the
lever seems a bit worn and sloppy, and it may be binding. One problem
is that I don't know if the principle of operation is that when the
belt is "loose" (disengaged), does it slip on the driven drum, or does
it pull back from the teeth of the drive????

I am now in Cocoa, and will check back in Vero. Thanks in advance for
the help! I really rely on this autopilot, and a new one is mucho
dinero.