[Boatanchors] Backlash in a National capacitor

[LeeCraner at aol.com]

Ian:
 
It could also be some prior owner disassembling the front of the gear box,  
pulling out the worm gear and then not preloading (rotating) the driven 
gear  halves.
 
Unscrew those four front screws and rotate the worm gear out.  Clean  
everything and relub.  Clean the driven gears, separate the halves and put  a few 
drops of oil to lub the halves.  Preload (rotate) the halves and  reinstall 
the worm gear.  Your backlash should be gone.
 
73
Lee WB6SSW
 
 
In a message dated 9/19/2012 2:57:40 P.M. Pacific Daylight Time,  
ianmwilson73 at gmail.com writes:

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
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