In addition to what Neil said:
If your pins are worn crooked, they aren't in alignment to the load.
Measure the difference between the thin part and thick part where the bushing contacts it with a caliper.
Take half that thickness, and insert a sheet metal shim on the side of the cage that held the thin side to square the sheave up with the load.
Re-string the cable, and see if your helm
If the issue is with the sheaves directly under the pedestal
, slack up the pedestal
bolts, and lower or raise the front or back, that same half distance and repeat the performance.
When you know the thicknesses you need, the under-pedestal wedge can be made out of wood. The turning blocks ahead of the quadrant you can have made up at a machine shop out of stainless or bronze bar stock. If you are doing it yourself, drill the holes first, make your thickness mark and grind down until you get a constant taper.
I like Super Lube for grease. Take a chip brush and cut the bristles down to a 1/2 inch long or so and pack the groove between the bristles full of grease and slather everything down, including the grooves in the quadrant.
What you ought to end up with, if the cables
are "just right" tension you can steer with one finger, a half a turn either side of center until the rudder
loads up. You'll also feel the pressure difference back fed through the system, when when you are motoring...
If you are starting with a new cable, tighten it down snug and take her sailing. The next day, adjust to center the wheel
and set the cables
to just right to take the stretch out.