B.  
Access

 (1)  
Location Zone
 317 APU Compartment-Exhaust Outlet, LH
 318 APU Compartment-Exhaust Outlet, RH

 (2)  
Access Panel
 317AL APU Access Door
 318AR APU Access Door

 C.  
Procedure

 S 866-002
 (1)  
Make sure the APU control switch on the P5 panel is OFF and attach a DO-NOT-OPERATE tag.

 S 866-003

 (2)  
Open these circuit breakers and attach DO-NOT-CLOSE tags.

 (a)  
P6 Main Power Distribution Panel
 1) 6K18 APU ALTN CONT

 (b)  
P83 Panel, E8 Aft Equipment Center
 1) APU PRIMARY CONT

 S 016-004
 (3)  
Open the APU access doors:

 (a)  
Open the latches on the APU access doors.

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SEE  A  LEAF SPRING SEAL  SEE  C 
SEE  B 
EXHAUST DUCT OUTER 
CLAMP LINER ACOUSTIC 
BOLT  BUSHING  SHIM  RIVET  DRAIN HOSE  A  EXHAUST DUCT INNER 
WASHER  WASHER  DUCT EXHAUST INNER  NUT 
LINER ACOUSTIC 
BOSS  NUT 
B  C 
Figure 601 APU Inner Exhaust Duct Inspection 

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 (b) (c)  Open the APU access doors.Engage the support rods for the APU access doors.
 S 016-005
 (4)  Remove the acoustic lining (Ref 49-81-03/201).
 S 226-006
 (5)  Make sure the support nuts have a torque of 400 |40 pound-inches (45.2 |4.5 newton-meters). (a) If the nuts are not tight, examine the bolts, bushing, and bosses:
 (b)  1) Remove the nuts, washers, bolts and bushings. 2) Measure the inner and outer diameter of the bushing. a) If the inner diameter is more than 0.4390 inch (11.15 mm), replace the bushing. b) If the outer diameter is less than 0.6252 inch (15.88 mm), replace the bushing. 3) Measure the diameter of the boss. a) If the diameter of the boss is more than 0.6255 inch (15.888 mm), replace the bushing.Install the bushings, bolts, washers, and nuts. 1) Tighten the nuts to 400 |40 pound-inches (45.2 |4.5 newton-meters).
 S 416-007
 (6)  Install the acoustic lining (Ref 49-81-03/201).
 S 416-008
 (7)  Close the APU access doors: (a) Do a visual check of the EGT bus bars: 1) Make sure the bus bars are not damaged. 2) Make sure no metal parts touch the bus bars. 3) Make sure the bus bars do not touch each other. (b) Disengage the support rods for the APU access doors. (c) Put the support rods in the clips on the inner side of the APU access doors.
 (d) (e) (f)  Make sure the insulation covers correctly attach to the APU compartment firewall.Close the APU access doors.Close the latches on the APU access doors.
 S 866-009
 (8)  Remove the DO-NOT-CLOSE tags and close these circuit breakers: (a) P83 Panel, E8 Aft Equipment Center 1) APU PRIMARY CONT
 (b)  P6 Main Power Distribution Panel 1) 6K18 APU ALTN CONT

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 S 866-010
 (9)  Remove the DO-NOT-OPERATE tag from the APU control switch on the P5 panel.
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