ENSTROM F-28F/280F SERIES MAINTENANCE MANUAL
Rev.
7
MM-9-2
Aug
22/16
(7) Install the hoist sling (T-0011) so the arms are between the pitch arm and the blade
retention assembly, over the lead/lag retaining nut, and outboard of the main rotor
damper rod-end. The sling arms are long enough to be double wrapped, if preferred
(Figure 4-3).
(8)
Attach the sling to a lifting device and slowly lift the hub assembly from the mast. The
hub must be lifted exactly parallel to the mast. If there are any side loads, the hub will
stick on the splines and will not come off. If the hub has been installed for a long
period of time, the hub puller (T-0174-1) must be used and the control rods must be
removed from inside the mast.
NOTE: It may be helpful to put the left-side wheel down to align the mast
vertically prior to lifting the hub assembly from the mast.
(9)
Install the hub assembly onto a hub stand.
C.
Main Rotor Hub – Disassembly
NOTE:
Mark all parts for reassembly in the same respective positions.
(1)
Remove the pitch links (2) and the walking beams from the pitch horns (1) (Figure 9-
1).
(2)
Remove the pitch horn (1) from the blade grip.
(3)
Remove the damper as follows (Figure 9-5):
(a)
Remove cotter pin (14), nut (13) and washer (12).
(b)
Remove bolt (11) and washer (12).
(c)
Pivot damper to remove spacers (15) on top and bottom of damper rod end.
(d) Remove nut (10) and washer (9) from inboard damper pivot bolt (7) and
remove bolt.
(e)
Remove the damper from hub assembly.
NOTE:
For damper reassembly, refer to Paragraph 9-5, G
(4)
Remove retention assemblies as follows (Figure 9-4):
(a)
Bend the tab up on hinge pin lock washer (4).
(b)
Install tool (T-0051-3) on nut (5) and remove nut.
(c)
Twist the grip slightly so that the hinge pin (3) will clear the pitch horn and slide
or tap the hinge pin from the assembly and remove assembly from the hub.
(d)
Remove the DU washers from both sides of the universal block recesses.
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