Well, I today took the bottom pulley assembly of the varidrive apart,
the part that is attached to the motor shaft, and that wobbles badly.
The wobble is not caused by the plastic bushing at all. It and the
green coating are just fine. (The green coating did have a few score
marks parallel to the shaft, probably from some grit that somehow got
inside.)

I knew I was in trouble when I went to loosen the two 1/4-20 setscrews
that fasten the varidrive pulley to the motor shaft, and found that both
were already loose. And then I noticed that the square key was a bit
cockeyed. Removing the pulley took considerable force, requiring a
prybar against the motor housing. The keyslot on the motor shaft
flares, becoming wider as one goes away from the motor housing, and the
metal was mushed outward. The slot in the pulley doesn't look too bad,
except for the busted-off corners.

The motor shaft does not appear to be bent, but I should verify this
with a dial indicator.

I assume that the pulley was a push fit on the motor shaft, when it was
young. Over the years, the setscrews loosened, and things drifted,
unnoticed. (Or someone forgot to tighten them after a repair.) The
whole assembly seems to have moved out about 1/2 or 3/4 inch, enough so
the end of the varidrive assembly was hitting the lathe cover, and
chewed a hole in it, so one could not properly install the cover. I
wondered about that when I got the lathe.

I filed away the obvious bumps on the shaft and the bore, but the pulley
still will not go on the shaft without far too much force. Tomorrow, I
will fit pulley to shaft using blue highspot and a small file, slowly.

I suppose locktite may be needed as well, as the motor shaft and/or bore
in the pulley is probably slightly tapered, and would fret in operation.
Before I took it apart, the pulley was solidly albeit crookedly stuck to
the shaft.

Anyone have any other ideas?

Joe Gwinn