IBM Selectric Service Manual

If no scale is available, the torque may be estimated by
holding the carrier while the clutch is engaged. The
torque limiter should slip readily yet return the carrier
positively without any hesitation when the carrier is re-
leased.
The adjustment is made by adjusting the eccentric stud
in
the torque limiter hub. If sufficient adjustment is not
available at the eccentric, the torque limiter sprint may
be shifted on the torque limiter hub by positioning the
torque limiter spring clamp.
NOTE: The carrier return clutch arbor should have an
end play of .004" to .006" between the torque limiter
hub
and the C-clip on the operational shaft. Adjust the
play by positioning the torque limiter hub laterally on
the shaft. The end play can be adjusted" easi Iy if .the
torque limiter spring is moved to the right, off the torque
limiter
hub.
CARRIER RETURN MECHANISM - LATE STYLE
Be sure that the print escapement and operational control ad-
justments are correct before attempting the carrier return ad-
justments.
1. Pawl Clearance - Adjust the clutch latch eccentric so
that the escapement pawl wi II clear the rack teeth by
.005" to .020" when the latch is being held down by the
keeper Fig. 147.1). NOTE: The latch actuating arm
collar should be adjusted for .001" to .007" end play of
the latch actuating arm (Fig. 147.1) prior to making the
pawl clearance adjustment.
The adjustment ensures that the escapement pawl will not
drag
along the rack during a carrier return operation and
that the pawl will be allowed to re-enter quickly at the
completion
of the return operation.
Clutch Latch
Eccentric
FIGURE 147.1 .. Pawl Clearance Adjustment
2. Clutch Latch Overthrow - Use the following procedure to
obtain the correct clutch latch overthrow and latch arm
height.
a. Carrier Return Lever - Position the carrier return lever
laterally on the left-hand operational pivot pin so
that the carrier return latch will hang vertical with-
out binding against its interposer. Be sure to tighten
the locking screw in the lever onto the flat portion
of the pivot pin (Fig. 147.2).
7':1~-- Carrier Return Lever
FIGURE 147.2 Carrier Return Lever Adjustment
b. Carrier Return Latch Arm Adjusting Screw (clutch
latch overthrow) - With the carrier return cam on
the high point, adjust the keeper latch arm adjust-
ing screw (Fig. 147.3) so that the clutch latch will
overthrow
the latching surface of the keeper by.030"
to .040". Be sure that the platen and feed rolls are
installed and the index selector lever is in the double
index position when
checking this adjustment. NOTE:
Contact assembly removed when making this adjust-
ment.
.030" to .040"
Overthrow
FIGURE 147.3 Clutch Latch Overthrow Adjustment
2-45

IBM Selectric Specifications

General

Type	Electric typewriter
Introduced	1961
Keyboard Layout	QWERTY
Carriage Return	Electric
Manufacturer	IBM
Printing Technology	Typeball (golf ball)
Power Source	AC Power
Power Supply	120V AC