TM 1-1520-238-23
5-97
5.19.
MAIN ROTOR HUB RETENTION NUT REMOVAL – continued
5.19.3. Removal
a. Check torque and remove 12 retaining ring
bolts (1).
(1) Remove lockwire from bolts (1).
NOTE
Check torque on retaining ring bolt by
tightening until it begins to turn.
Bolt holes are identified on retaining
ring.
(2) Check and record the torque value on each
bolt (1) in the following order: 1, 2, 3, 4, 5, 6,
7, 8, 9, 10, 11, 12. Use torque wrench.
(3) If the torque on any bolt (1) is below 125
INCH-POUNDS, check torque on two adja-
cent bolts.
(4) If either torque is below 175 INCH-POUNDS,
replace main rotor hub retention nut (2).
(5) Remove bolts (1) from retaining ring (3) in the
following order: 12, 11,10, 9, 8, 7, 6, 5, 4, 3, 2,
1.
b. Remove retaining ring (3) from mast (4).
c. Remove retention nut (2).
(1) Install two bolts (1) in retention nut (2) 180
degrees apart.
(2) Use two bolts (1) as handles to turn retention
nut (2) clockwise.
(3) Remove retention nut (2) from mast (4).
(4) Remove bolts (1) from retention nut (2).
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M04-212-2
4
10
2
11
7
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5
9
1
8
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12
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