ENSTROM F-28F/280F SERIES MAINTENANCE MANUAL
Rev.
7
MM-11-25
Aug
22/16
C. Gearbox – Installation
(1) Install main rotor hub on gearbox. See Section 9-1-B for hub installation
procedure.
CAUTION: Hub must be installed with index marks on spline adapters
aligned to properly phased spine on rotor shaft, or serious flight
control problems will result.
(2) Install push-pull rods and swashplates if required. See Section 12, Flight
Controls, for swashplate installation procedures.
(3) Secure collective walking beam to swashplate and center pivot point on
gearbox. Torque bolts.
NOTE:
Pivot bolts at walking beam swashplate connection are safety wired
with .032 wire.
(4)
Lightly coat the top of the pylon mount pads and the shank of the mount bolts
with Loctite Silver Grade anti-seize.
(5)
Using sling T-0011, lift gearbox into position on pylon.
(6)
Install gearbox mount hardware (4 places). Torque bolts.
NOTE: Gearbox mount bolt torque is 240 in-lbs/27.1 Nm. Torque seal
should be applied to the installed hardware for slippage indication.
NOTE: NEW hardware must be used when re-installing a main rotor
gearbox, as the self-locking feature of the recommended nuts
precludes re-use.
(7)
Install jackstrut and pulley assembly, idler assembly, and drive belt.
(8)
Connect temperature probe adapter to fitting on bottom of gearbox.
(9)
Connect collective push-pull rod to collective walking beam. Install fiberglass
cover.
(10) Connect lateral and longitudinal push-pull rods (1 & 2) to lower the
swashplate. See Section 12, Figure 12-20 for correct hardware installation.
(11) Install baggage box. See Section 8, Structure, for the baggage box
installation.
(12) Install bulkhead over gearbox pinion area.
(13) Install fuel tanks and connect fuel lines.
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