(3)  
Support lower shroud, open shroud latches, and remove shroud.

CAUTION:  EXERCISE EXTREME CARE NOT TO DAMAGE SHROUD DRAIN LINES WHEN HANDLING SHROUD.

(4)  
Remove placard from BATTERY switch.

(5)  
Start APU (AMM 49-11-0/201).

CAUTION:  TO AVOID DAMAGING APU, OBSERVE OPERATING LIMITS (AMM 49-11-0/201).

(6)  
With no load applied, APU frequency meter should stabilize at 405-410 Hz.

(7)  
If steady state "no-load" governed frequency is not within limits, install tachometer-generator (AMM 49-11-0/201).

(8)  
Start APU (AMM 49-11-0/201).

(9)  
Compare "no load" governed frequency in conjunction with the RPM indicator.

NOTE:  If the speed is out of limits, adjust no more than 1/12 (half a flat of nut) of a turn. Any adjustment of the Governor greater than 1/12 of a turn requires a check of the fuel control crack pressure.

(10)
APUs WITHOUT ALLIEDSIGNAL SB GTCP85-49-7096 AND FUEL CONTROL UNIT WITHOUT THE TIMED ACCELERATION CONTROL; if the stable APU frequency is not between 405-410 Hz, adjust the governor for the fuel control unit:

(a)  
Do the APU normal shutdown (AMM 49-11-0/201).

(b)  
Use the screwdriver and wrench assembly to loosen the locknut on the governor adjustment screw.

(c)  
If the APU frequency is too low, turn the governor adjustment screw clockwise.

(d)  
If the APU frequency is too high, turn the governor adjustment screw
counterclockwise.

(e)  
Tighten the locknut on the governor adjustment screw.

(11)
APUs WITH ALLIEDSIGNAL SB GTCP85-49-7096 AND FUEL CONTROL UNIT WITHOUT THE TIMED ACCELERATION CONTROL; if the stable APU frequency is not between 405-410 Hz, adjust the governor for the fuel control unit:

(a)  
Use the screwdriver and wrench assembly to loosen the locknut on the governor adjustment screw.

(b)  
If the APU frequency is too low, turn the governor adjustment screw clockwise.

(c)  
If the APU frequency is too high, turn the governor adjustment screw
counterclockwise.

(d)  
Tighten the locknut on the governor adjustment screw.

(12)
APUs WITHOUT ALLIEDSIGNAL SB GTCP85-49-7096 AND FUEL CONTROL UNIT WITH THE TIMED ACCELERATION CONTROL; if the stable APU frequency is not between 405-410 Hz, adjust the governor for the fuel control unit:

(a)  
Do the APU normal shutdown (AMM 49-11-0/201).

(b)  
Use the jamnut wrench to loosen the jamnut on the governor adjustment nut.

(c)  
If the APU frequency is too low, turn the governor adjustment nut clockwise with the adjuster wrench.

(d)  
If the APU frequency is too high, turn the governor adjustment nut counterclockwise with the adjuster wrench.

(e)  
Tighten the jamnut on the governor adjustment nut.

(13)
APUs WITHOUT ALLIEDSIGNAL SB GTCP85-49-7096 AND FUEL CONTROL UNIT WITH THE TIMED ACCELERATION CONTROL; if the stable APU frequency is not between 405-410 Hz, adjust the governor for the fuel control unit:

(a)  
Use the jamnut wrench to loosen the jamnut on the governor adjustment nut.

(b)  
If the APU frequency is too low, turn the governor adjustment nut clockwise with the adjuster wrench.

(c)  
If the APU frequency is too high, turn the governor adjustment nut counterclockwise with the adjuster wrench.

(d)  
Tighten the jamnut on the governor adjustment nut.

(14)
Do the APU normal shutdown (AMM 49-11-0/201).

(15)
Do the above test steps again until the governor speed adjustment is correct.

(16)
Placard BATTERY switch.

501 
49-11-0 Page 504  BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.  Apr 01/97 

504 
May 01/99  BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.  49-11-0 Page 505 

(17)
Restore airplane to normal configuration.

(a)  
Position lower shroud against upper shroud and close shroud latches.

CAUTION:  MAINTAIN A MINIMUM CLEARANCE OF 0.18 INCH BETWEEN ENGINE PLUMBING, FIRE DETECTOR, CLAMPS AND INSIDE SURFACE OF LOWER SHROUD.

(b)  
Disengage APU compartment access door support rods and stow rods. Close and latch access door.

(18)
Remove placard from BATTERY switch.

E.  Bleed Air Valve Opening Rate Test
NOTE:  It is not necessary to do the opening rate test for the bleed air valve after you replace the APU, fuel control unit or bleed air valve. You can use this test for troubleshooting or adjustment of the bleed air valve.
　
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