Nortel DMS-10 Series Installation, Operation And Maintenance Manual page 459

Procedure 6-6
Cooling fan replacement
Step Description
54
Remove the rear panel of the chassis to be worked on. Figure 6-6 shows the eight screws
to remove. Save the screws.
55
Remove the two screws securing the fan mounting bracket in the chassis. These screws
are on the outside of the chassis, in the upper left corner of the right hand panel, as seen
from the rear. See Figure 6-6. Support the fan assembly with your hand while removing
the two screws.
56
Remove the fan mounting bracket from the chassis. Slide the base of the bracket 1/2-inch
to the left and then pull back 1-inch from the center of the chassis until the bracket is free
of the chassis base.
57
Disconnect the connector from the Fan Filter PCA. Connector is on the Fan Filter PCA on
the bottom rear of the bracket.
58
Remove the fan. With the bracket balanced on the lip of the BMC chassis, remove the four
bolts in the corners of the bracket. Save the bolts.
59
Mount the replacement fan. With the bracket balanced on the lip of the chassis, reinstall
the four bolts in the corners of the bracket. Use the same four bolts removed in step 8.
60
Connect power to the fan. Connect power cable to the Fan PCA on the bottom rear of the
chassis.
61
Install the fan mounting bracket. Push in 1-inch and to the right 1/2-inch; register and lock
the slots on the bracket with the pins on the chassis base.
62
Reinstall the two screws removed in step 5 to secure the bracket in the chassis.
Note: When replacing the bolts, carefully align them before tightening to avoid stripping. Tighten
the bolts, alternating until all are equally tight. Do not "cinch down" any one bolt until all are
properly aligned; no binding or force needed to turn.
63
Reinstall the rear panel of the chassis just worked on. Use the screws saved in step 4.
64
Clean the foam filter using the Cleaning the Fan Foam Filter procedure.
65
Reinstall the front panel on the A chassis. Snap the cover in place.
BMC II BISYNC Operation, Administration, and Maintenance Guide BMCB001 and up
Section 060-INDP-610 Maintenance Procedures Guide 6-21
Sheet 2 of 2