ENSTROM F-28F/280F SERIES MAINTENANCE MANUAL
Rev.
7
MM-9-3
Aug
22/16
NOTE: If shims are installed behind DU washers, remove and save for
reassembly.
NOTE:
For retention disassembly, see Section 9-2, Retention Disassembly.
(5) Remove bolts (1) and (2) from the walking beam brackets (3) and remove the
brackets (Figure 9-3).
(6)
Remove the dust cover (4).
(7)
Bend the locking tabs (6) out of the recesses in the retaining nuts (5). Install tool (T-
0051-3) on the nuts and remove the nuts and the washers.
(8)
Turn the hub assembly over and remove the locking keys (10) from the retaining nuts
(9).
(9)
Using tool T-0003, remove the nuts, shims (8), and DU washers (7).
(10) Turn the hub assembly over and remove the hardware (11) from the center hub
adapter.
(11) Remove the upper and lower spline adapters (12 and 18) by tapping them from the
hub plates with a nylon drift.
(12) Remove the dowel pins (13) from the hub plates (14 and 17) and the center spacer
(16) by tapping them through with an aluminum drift.
(13) Remove the grease fittings (19) from the hub plates (6 places).
WARNING: Use extreme caution when removing or installing the blade and grip
assemblies to prevent from injuring personnel.
WARNING: Use protective gloves when handling heated parts.
NOTE:
Heating the assembly can be facilitated by using an oven.
(14) Heat the upper hub plate to approximately 250°F/121°C and lift the hub plate from
the universal blocks (15). Tap with a plastic mallet if necessary.
(15) Heat the lower hub plate to approximately 250°F/121°C and tap the universal blocks
from the hub plate.
D.
Inspection – Refer to Table 9-1 for detailed inspection requirements.
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