TM 1-1520-238-23
Change 4
6-439
6.99.
MAIN ROTOR MAST MOUNTING BOLT REPLACEMENT (AVIM) – continued
d. Install 18 bolts (5) and washers (6) through
mast base (2).
e. Install retainer (1) on mast base (2).
(1) Position retainer (1) over bolts (5) and mast
base (2).
(2) Install six screws (3) through washers (4),
retainer (1), and mast base (2).
CAUTION
To prevent damage to main rotor drive
shaft and oil seal, lockwire shall be not
less than 0.120 INCH from edge of retain-
er opening.
(3) Lockwire six screws (3) in sets of three.
(a) Use double twist method. Use wire
(item 224, App F).
(b) Twist pigtails outboard away from rotor
mast opening.
f. Inspect (QA).
g. Install mast base oil seal retainer (para 6.100).
END OF TASK
4
3
5
6
2
1
M04-3251-4
3
0.120
M04-3251-3A
