CAN OCCUR.
(b)
Install the bellcrank rig pin.
(c)
Install the three rig pins (PWA 85393) into the rig pin holes of the IGV, 5th-, and 6th-stage unison ring.
(d)
Install the rig pin (PWA 85394 or PWA 86197) into the 7th-stage pin hole of the unison ring.
(e)
If you can install all the rig pins, remove all of the rig pins from the unison ring and the bellcrank.
(f)
If you cannot install one of the rig pins of the unison ring, adjust the unison ring with the steps that follow: 1) Remove the rig pins from the unison ring and the bellcrank
rig pins.
2) Move the control handle on the hydraulic cart to the neutral position.
3) Turn the valve handle for the air supply to the closed
position.
4) Disconnect the unison ring linkage.
5) Disassemble the unison ring linkage.
a) Discard the key washers.
6) Assemble the unison ring linkage with the new key washers.
7) Adjust the unison ring linkage with the steps that follow:
a) Install the PWA 86097 rig pin. b) Turn the adjusters until you can install all the rig pins into the unison ring.
c) Tighten the nuts, at each of the rod end bearings which are changed, to a minimum of 15-22 pound-inches (1.7-2.5 newton-meters) plus the torque which is necessary to turn the nut on the bellcrank clevis bolt. 1 Install the cotter pins.
_
d) Examine the adjusters and rod end bearings for the correct installation.
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
75-31-00
ALL ú ú N02 Page 514 ú Jun 18/99
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
e) Install a piece of wire into the inspection holes at
the two ends of each adjuster.
NOTE:____ If you can not put the wire through, the
installation is satisfactory. If you can put
the wire through either end, you must
disassemble the linkage and adjust it as
necessary until the wire will not go through.
f) With the rod end bearings correctly installed, tighten
the jamnuts at each rod end to 115-150 pound-inches
(13.0-17.0 newton-meters).
CAUTION: MAKE SURE YOU REMOVE ALL OF THE RIG PINS FROM THE
_______ UNISON RINGS AND THE BELLCRANK. IF YOU DO NOT REMOVE ALL OF THE RIG PINS, YOU CAN CAUSE DAMAGE TO THE ENGINE.
g) With all of the rig pins removed, operate the hydraulic cart to supply 250-300 psi hydraulic pressure to the PF port.
h) If an electrical switch box is not used, push the actuation switch to retract and extend the actuator through its full movement. 1 Do this step a minimum of three times.
_ 2 Stop the actuator rod in the fully
_ extended position.
i) If an electrical switch box is not used, do the steps that follow: 1 Install a crowsfoot and a wrench on the flats of
_ the bellcrank adjacent to the 5th-stage adjuster links.
2 Push up on the wrench to move the bellcrank to the
_ closed position until the position slots approximately align.
3 Remove the crowsfoot and wrench.
_ 4 Operate the hydraulic cart to supply 250-300 psi
_ hydraulic pressure to the PF port. 5 Extend the actuator to the full open position.
_
6 Do these steps above one more time.
_
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
75-31-00
ALL ú ú N02 Page 515 ú Jun 18/99
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
////////////////////////A / PW4000 SERIES /747-400 / ENGINES/MAINTENANCE MANUAL ////////////////////////
j) Install the PWA 86097 rig pin. k) Install the three PWA 85393 rig pins into the rig pin holes of the IGV, 5th- and 6th-stage unison rings. l) Install the PWA 85394 rig pin into the rig pin hole on the 7th-stage unison ring.
m) If you cannot install one of the rig pins into the unison ring, you must do the steps from above which adjust the adjusters again.
n) Remove all of the rig pins.
o) Bend one set of the tabs on the key washer to the
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：747-400 AMM 飞机维护手册 大气 AIR 2(27)
