Pulley And Clamp Replacement - IBM System/34 Maintenance Manual

25-710
PULLEY AND CLAMP REPLACEMENT
1. Reinstall the pulley, clamp, and clamp screw
G.
(Keep the screw loose so the motor shaft can turn
inside the pulley.)
2. Carefully reinstall the drive band ends on the
pulley pin
e.
Reinstall the band clamp (with the
notch facing away from the stepper motor) and
screw.. (Do not tighten the screw.)
3.
Loosen the two mounting screws
e
and let spring
tension position the idler.
4. Tighten the mounting screws and center the drive
band on the idler pulley as shown
O.
5. Reinstall the diskette drive control card and the
card retainer.
6. Reinstall the head cable on the diskette drive
control card.
7. Turn the' stepper motor pulley by hand to about
cylinder 40 and insert a timing pin
O.
8. Disconnect the drive motor power connector.
DANGER
Voltage is still present at the power connector
when the pulley and clamp are disconnected
and power is on.
9. Remove the attachment card at A-A2L2 to prevent
the stepper motor access lines from being
activated by an external source.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
34
25-710
Set Power to I (operator panel).
,,/-
..........
,
Install a jumper
e
from TPA 13 (ground) to THP11
(-align access 0).
Make the gap
G
between the pulley and the
casting the same as the gap that was recorded in
25-700, step 9.
f
,~'"
1 '".
/
Tighten the clamp screw
G.
Remove the timing pin
O.
Remove jumper
e.
( "
I
Tighten the band clamp screw • . (Ensure that
\''--'
~
the drive band is straight.)
Turn the stepper motor pulley by hand and check
that the drive band is centered
0
on the idler
pulley in all of the head / carriage assembly
movement (cylinder 00 to cylinder 76).
If the drive band is centered, go to step 19. If the
drive band is not centered, go to 25-740, step 4.
Go to 25-480, step 5.
C'_~',
C ' "
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