IBM Selectric Reference Manual

MACHINE LOCKUP
19.0 Machine Lockup
19.1 The most common causes of Machine Lockup are:
a. The Cycle Clutch Spring may be broken, out of
adjustment (Section 15.0), or is in need of lub-
ri cation.
b. Idler gear binding. Remove and lubricate with
#10 oi I.
c. Remove the type element, then recheck for lock-
up. If no lockup is encountered, a II typehead
motion adjustments and print shaft timing must be
checked.
d . The Pri nt Sleeve and beari ngs may be dry or worn .
e. Binds in the Carrier and Rocker Assembly.
f. Check the Print Cam Follower for bi.nds.
g. Oversize Cycle Clutch Pulley and Hub Assem-
bly. (Section 15.5)
h. Shift Cam Back-Up Roller adjustment. (Section
4.8)
i. Operation Shaft binds or Shift Cam adjustment.
(Section 4.0)
j. Shift Spring <;:Iutch is dry or requires adjustment.
(Section 4.0)
k . Dry center beari ng. (Secti on 15.7).
FAI LURE TO START
20. 0 Fai lure to Start
I f motor attempts to dri ve, check:
20.1 Centrifugal ~Iutch Binding (See Also 21 .3)
a. I/O PRINTER CENTRIFUGAL CLUTCH
A sintered iron pulley with a Mylar ® insert and
nylon clutch pawls has been released to eliminate
motor clutch lockup and pu Iley wear.
The nylon pawls are used to eliminate wear on
the teeth of the bronze pu Iley .
The
sintered iron pulley has a slightly larger in-
side diameter to accept the Mylar ® sleeve.
When rep laci ng the motor pu lIey, c lean the mo-
tor shaft thoroughly to prevent future binding. A
piece of fine emery cloth may be used while run-
ning the motor. Remove any abrasive material,
using IBM cleaning fluid, prior to assembly.
NO,TE: If emery cloth is used to clean the motor
shaft, the enti re paw I assemb Iy must be removed,
as a safety hazard is present if the emery cloth
contacts the moving pawls and springs.
Lubricate the new sintered iron pu lIey with IBM
# 10 oi I during initial assembly and thereafter as
required.
All parts necessary to convert to the new clutch
assembly are available under BIM 1272045.
b. Cycle Clutch Pulley oversize.
c. Dry or binding Center Bearing (15.7).
5-26
d. Binding Operational Shaft
e. Dry or binding Shift Clutch
20.2 Motor Fai Is to Drive
20.3
1. Thermal cut-out open.
2. Dry motor bearings.
Capacitor Start Motor
In order to eliminate problems which have existed
wi ththe shaded po Ie motor and clutch, an improved
capacitor start motor is avai lable for use in instances
where repetitive fai lures have been encountered
with the previous clutch arrangement. The new cap-
acitor start motor uses a 4 mfd. capacitor which pro-
vides much greater starting torque than previous cap-
acitor start motors. This new capacitor start motor
wi
II start the I/O under any load conditions with
normal line voltages.
Parts may be. ordered as follows:
Part
No.
1166082
1272458
Desc
ri pti on
Motor, 115V, 60 Cycle
BIM, Motor+Mounting
NOTE: This BIM contains motor and all hardware
and a temp late necessary to mount the motor.
20.4 Worn or Broken Belt
Drive belts may be breaking on machines receiving
heavy usage, or machines over a year old. The next
time the cyc Ie shaft is removed for replacement or
adjustment, the motor belt should be replaced, re-
gardless of its age or condition. It is a Iso recom-
mended that an extra be It be p laced on the cyc Ie
shaft.
The belt should be slipped over the cycle shaft and
tied with wire or lacing cord as illustrated below.
Figure 20.0
The motor belt should be turned inside-out so that the
smooth portion of the belt is rubbing on the cycle
shaft. It shou Id be folded over as shown be low and
wrapped, and then left hanging under the cycle
shaft and slightly toward the front of the machine.
Since it will be difficult to describe exactly how to
fo Id and wrap the be It, you must insure that after the

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