[Boatanchors] Backlash in a National capacitor

[Ian Wilson]

I have a National 4-gang HRO-type variable capacitor here. It has
noticeable backlash.
Removing the top of the gearbox and looking at the two large driven gears,
I can see
that when the direction of rotation changes, there is a small dead zone as
the two
gears are pulled into alignment.

Presumably this is caused either by the springs losing tension (about which
I can't
do much), or by excessive drag on the shaft that rotates the capacitor
rotors. Assuming
that the problem is drag, how should I adjust/lubricate which bearings to
lessen this?

73, ian K3IMW