TM 1-1520-238-23
6-199
6.40.
ENGINE NOSE GEARBOX PRELOAD SHIM REMOVAL/INSTALLATION (AVIM) – continued
(5) Compare thickness of removed preload shim
against calculated dimension C.
(a) If thickness of removed preload shim is
within 0.001 INCH of dimension C, re-
use preload shim. Use caliper set.
(b) If thickness of removed preload shim is
not within 0.001 INCH of dimension C,
discard removed preload shim and obtain
new preload shim. Use caliper set.
(c) Surface grind new preload shim to meet
tolerance requirements and clean prior to
installation (para 6.40.4).
6.40.6. Installation
a. Install preload shim (1) in gearbox (2).
b. Inspect (QA).
c. Install engine nose gearbox rotor output shaft
seal (para 6.39).
END OF TASK
DIM. A
MINUS DIM. B
EQUALS
PLUS
EQUALS DIM. C
+ 0.004 INCH
± 0.001 INCH
M04-3812-4
CALCULATION OF PRE-LOAD SHIM
THICKNESS
M04-3812-3
2
1
