(a)  
Remove the bolt (1) from the cushioned clamp (2) that attaches the W1 cable to the tab on the upper front mount bracket of the SCU.

 (b)  
Loosen the cushioned clamp (2) from the mount bracket, install the bolt (1) into the same hole in the tab of the mount bracket and tighten sufficiently to engage the self-locking threads of the nut plate.

 S 032-021-N00
 (6)  
If the SCU has the flex hose assembly (3) for the multiplexing option, remove the top connector of the flex hose assembly (3) from the bottom side of the SCU.

 (a)  
Install a protection cover to the flex hose opening.

 S 032-022-N00
 (7)  
Disconnect the ground cable (5) for the SCU:

 (a)  
Remove the bolt (6), washer (7) and nut (8) from the ground cable (5) that is attached to a bolt hole in Flange B2.

 (b)  
Install the bolt (6), washer (7) and nut (8) into the same bolt hole in Flange B2 and tighten the bolt (6) sufficiently to engage the self-locking threads of the nut (8).

 S 032-023-N00
 (8)  Remove the SCU from the flight position on the fan case:
 NOTE: It is necessary to have two persons do this procedure.
____
 (a)  
Remove the two bolts, washers and nuts from the lower SCU mount bracket on Flange A1.

 (b)  
Remove the two bolts, washers and nuts from the lower SCU mount bracket on Flange B2.

 (c)  
Remove the two bolts, washers and nuts from the upper SCU mount bracket on Flange B2.

 (d)  
Have another person very carefully hold the SCU, and remove the two bolts, washers and nuts from the upper mount bracket on Flange A1.

 (e)  
Remove the SCU with the mount brackets from the fan case.

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A
747-400
MAINTENANCE MANUAL

 S 422-024-N00
 (9)  
Install the SCU in the storage position on the left side of fan case:

 (a)  
With the electrical connectors on the SCU pointing rearward, install the SCU to the upper left side of the fan case at the

 10:30 o'clock position.

 (b)  
Put the forward mount brackets to the rear of Flange A1 and the rear mount brackets to the rear of Flange B2.

 (c)  
Align the bolt holes in the mount brackets with the bolt holes in the flanges with the bolts, threads lubricated with engine oil, washers and nuts.

 (d)  
Tighten the bolts to 85-95 pound-inches (9.6-10.7
 newton-meters).

 (e)  
Attach (to temporarily store) the cable clamps, ground cable, harness connectors and flex hose assembly (if necessary) for shipment and transportation.

 (f)  
Close the fan cowl panels (AMM 71-11-04/201).

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SUPPLEMENTAL CONTROL UNIT (SCU) - REMOVAL/INSTALLATION
______________________________________________________
 1.  General
_______
 A.  This procedure gives the instructions for the removal and installation of the Supplemental Control Unit (SCU).
 B.  The SCU is installed on the fan case at the 3 o'clock position.
 C.  Open the right fan cowl panel to get access to the SCU.
 TASK 73-21-15-004-001-N00
 2.  Remove the Supplemental Control Unit (SCU) (Fig. 401)
__________________________________________
 A.  References
 (1)  
AMM 71-11-04/201, Fan Cowl Panels

 B.  
Access

 (1)  
Location Zone
 412 Engine 1 - Fan Case 3 o'clock
 422 Engine 2 - Fan Case 3 o'clock
 432 Engine 3 - Fan Case 3 o'clock
 442 Engine 4 - Fan Case 3 o'clock

 (2)  
Access Panel
 414 Right Fan Cowl Panel - Engine 1
　
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