alignment, caster adjustment

[bcjm]

1971 280SL. I went to an alignment shop after replacing my kingpin. They did the toe and camber but couldn't (don't know how to) do the caster.  

When I did my kingpin, I can see how the steering knuckle going up/down/turning when rotating the cam bolt.  I figure that is how they adjust the camber.  I couldn't figure out how to adjust the caster so I can't argue with the shop.  I came home with caster 1.39 and 2.03 degree.  The car ride straight, does not pull to one side and the wheels return to center after the turn.

Should I redo my alignment?  How do you adjust the caster?

[BHap]

On the upper, outer control arm bushing there is a "star" washer.  This is the large washer that has notches all around the outside.  The washer has a small "nub" near the center hold that fits into the end of the upper control arm threaded bushing.  By spinning this washer, the upper bushing turns and moves the upper kingpin mounting point forward or back.  I would guess that there is a special tool, but that a hammer and punch would also work.  I'd go back and ask to have it set properly, after all of your work - I'm sure you want to have it right....

Bob Happe
Pittsburgh, Pa
1970 280SL, white/black 4 speed

[bcjm]

Now I remember that special looking washer.  I put it in without paying any attention. I centered (try to) the upper control arm threaded bushing when installed.  Are you saying the "star" washer is used to turn the steel bushing when spun?  Interesting.  I hope I had the "slot" on the steel bushing faced the right direction.

[A Dalton]

The washer adjustment for turning the threaded bushing is only a final tweaking adjustment to get castor equal on each side . They want that centered as much as possible so that you do not crush/compress the foward/rear seals.
 The actual castor adjustment is done with the eccentic bolt/lock adjusters at the front mounts of the flat springs.