TB 1--1520--240--20--144
NOTE
The forward and aft swashplate rotating ring lower seal retainer nuts may
be replaced on aircraft. However, if an unserviceable swashplate station-
ary ring is found, replace swashplate assembly. If unable to change/re-
place the nut with swashplate on aircraft due to any reason, then remove
swashplate and accomplish off aircraft.
WARNING
If a nut, washer, bolt, or other foreign object is subsequently
dropped during replacement, it must be recovered prior to
flight. Failure to secure the dropped item will result in a red
// X // condition for that aircraft until the item has been recovered.
a. If incorrect nuts are found, but no damage is found on the forward and aft stationary swashplate (on
aircraft) --
(1) Have helper slowly rotate blades and position incorrect nut in an open area of the swashplate,
which will allow it to be easily removed.
CAUTION
Have a helper hold the rotor blades in place
so that the swashplate rotating ring does not move.
(2) Replace all incorrect swashplate lower seal retainer nuts with the correct nut. If P/N
FN22M-624 self-locking nuts are not available, P/N HS4143-4 is an acceptable substitute. Torque nuts to a
dry torque of 350-380 inch-pounds.
b. If damage due to incorrect nut installation is found on either the forward and/or aft swashplate, re-
place swashplate assembly.
c. Purge all on-hand stock of incorrect swashplate lower seal retainer self locking nuts.
NOTE
The incorrect nut height measures 0.425" -- 0.455" (NAS 1758-L6) The
correct nut height measures 0.350" maximum (FN22M-624)
10. Supply/Parts and Disposition.
a. Parts Required. Items cited in paragraph 12c may be required to replace defective items.
b. Requisitioning Instructions.
All requisitions shall use project code (CC 57-59) "X-1-L" (X-RAY-ONE-LIMA).
NOTE
Project code "X1L" is required to track and establish a data base of stock
fund expenditures incurred by the field as a result of message actions.
c. Bulk and Consumable Materials.
NOMENCLATURE
PART NUMBER
NATIONAL STOCK NUMBER
NUT, SELF-LOCKING
FN22M-624 or HS4143-4
5310-01-184-0354
4