IBM 3270 Maintenance Manual page 229

Check that the diskette drive belt is correctly
installed on the pulleys and is in good condition.
Type 1
Bottom View
Tvpe2
IS THE DRIVE BELT INSTALLED ON THE
PULLEYS CORRECTLY AND IN GOOD
CONDITION?
NO If the belt is installed incorrectly, correct
it; if it is not in good condition, replace it
(see Section 5, "Removal/Replacement and
Adjustments").
YES Replace the Diskette Drive (see Section 5,
"Removal/Replacement and Adjustments").
3-600-30 Maintenance Information