IBM Selectric Manual page 10

A. REST POSITION
1/16" to 3/32"
B.
RELEASED POSITION
FIGURE
22.
Shift Clutch Spring Retaining
Plate Adjustment
NOTE:
If
sufficient ad justment cannot be obtained with
the retaining plate, the right end of the cl·,ltch spring
may be placed in another hole in the ratchet. The ad-
justment can then be refined with the plate.
3. Shift Cam Stop - Adjust the stop so that the shift clutch
ratchet has .010" to .030" rotary motion between the
shift cam stop and the shift release arm with the mech-
anism at rest (Fig. 23).
Shift Release Arm _ _ _ _
Holding Inner Lug
Of Ratchet
• 010" to .030"
Sh i ft Cam Detented
FIGURE
23.
Shift Cam Stop
A(~jllstment
8
The adjustment insures that the shift cam will not be al-
lowed to travel past the detented position.
NOTE: The stop should not bind against the spring
clutch when the adiustment is rr:c:de.
CAUTION: Be sure the cam is detented at the time the
stop adjustment is checked.
4. Shift Cam Brake - The shift cam brake should be adjusted
to have .035" to .040" bite on the braking rib of the
cam (Fig .. 24). That is approximately 1/2 the thickness
of the rib.
5.
.035" to .040"
1/2
Thickness Of
FIGURE
24.
Shift Cam Brake Adjustrnent
Excessive braking action could prevent the cam from
reaching the detented position in the lower case. Insuf-
ficient braking action would result in a noisy shift oper-
ation and expose the mechanism to possible ports break--
age.
Shift Release - Adjust the shift release link so that the
release occurs when the key
It;
vel' has been depressed 2/3
of the full travel. As the keylever is allowed to restore
from a fully depressed position, the shi ft should again
operate when 2/3 travel ofthe keylever has been reached.
A balance between the two releasing points insures the
proper adjustment .
NOTE: The shift bellcrank attached to the right end of
the bail shouldbesetpriorto making the link adjustment.
For proper leverage the bellcrank should operate with
same over-center travel in both directions.
6. Shift Lock - Adjust the shift lock brucket up ur down so
thattheshiftlockengages just as the shift release occurs
orslightlyafterward. The lock should never engage be-
fore the shift release occurs. Keep the lock bracket ver-
tical during the adjustment.
The shift lock must be released easi Iy by depressing either
shift keybutton.
7. Shift Interlock
a.
723 and 725 - With the shi ft interlock on the high
pointofthe cam, adjust the interlock by its adjust-
i ng screw so that the ti p j LJst bottoms between two
teeth on the shift clutch ratchet (Fig. 25a).