[GreenKeys] 28KSR keyboard adjust question

[Nick England]

Greenkeyers have been really helpful and I hope I am not too much of a pest.
I'm new to this and don't have a manual other than what have found on the
web so far.

This is a skintight 28KSR - I believe this is a Mk III keyboard.

Here's the symptom - from the keyboard, pulses 3-5 always come out as
spaces.
So  "LTRS" (MMMMM) produces an "A" (MMSSS).
And "B" (MSSMM) produces an "E" (MSSSS), etc.
A and E are the only characters that get generated correctly!

All 5 code bars are latching OK - what's happening is that the code bar bail
is pulling to the left too early and resetting the code bars  - by the time
the signal generator camshaft gets around to pulse 3, the code bars have
already been reset and so the signal generator produces spaces for pulses
3-5.

The code bar bail is pulled back to the left by an eccentric on the signal
generator camshaft, but I can't figure out how to adjust the eccentric
timing. Adjusting the stud (154017) where the eccentric follower attaches to
the code bar bail doesn't help - it just makes sure the code bar bail gets
pulled back far enough to latch properly.

Could be there is something I don't understand about the code bar bail
operation - it springs to the right when a key is depressed and then slowly
gets pulled back to the left by the eccentric on the signal generator
camshaft. Is the code bar bail supposed to stay latched on the right until
late in the cycle? I can't see how, but if so I guess my problem would be in
the latch mechanism.
Any hints would be appeciated.

Boy, my hat is off to the folks who designed these fiendish contraptions.
And I know, I am just getting my feet wet with the easy stuff and ain't seen
nothing yet.
cheers,
Nick

[Note - I think this is a Mk III keyboard - it does not match the June 1953
model 28 principles of operation manual (216B) - the code lever bail
eccentric follower is different and so are the code bar transfer levers - my
keyboard does look like the photos in 1000-3 preventative maintenance tech
manual and the Mk III drawings in the April 1963 M28 parts book (1149B)]