IBM 01 Maintenance Manual page 324

MODEL B4
CUSTOMER ENGINEERING
The No.1 Backspace Pawl Bottomed Evenly Between Teeth
Figure
34.
Checking Guide Pin Verticalness
Figure 35. Operating Link Adjustment
5. BACKSPACE OPERATING LINK. Adjust so that
when the cam is at rest, the backspace pawl spring
lugs will clear the riveted stud in the backspace pawl
support by
:132"
(Figure 35).
If
the cam fails to move
the carriage far enough to backspace properly, this
clearance may be increased slightly.
6. THE PAWL ALIGNING LINK is adjusted to fully
align the pawls when the backspace cam is on its high
point (Figure 36). Unhook the aligning link and place
the backspace cam on its high point. Pull the aligning (
link to fully align the escapement pawls and match
the pin in the clevis to the working side of the elong-
gated hole in the backspace bellcrank. Check for full
alignment at the high point of the backspace cam by
checking for movement to the left by the escapement
pawls when pulled or pushed with a spring hook.
There should be no movement, but this may indicate
over-alignment. In this case back off one-half turn
on the aligning link and check the movement of the
escapement pawls again to eliminate any choke-off.
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