ENSTROM F-28F/280F SERIES MAINTENANCE MANUAL
Rev.
6
MM-9-31
Apr
7/15
H.
Damper
– Installation
(1) Remove cotter pin and nut from center walking beam bolt. Slide bolt back to
end of threads.
(2) Install damper assembly on main rotor hub.
(3) Install chamfered washer on inboard damper bolt.
NOTE:
Chamfered side of washer must go against bolt head.
(4) Install inboard bolt through hub plates and damper. Install bottom washer and
nut but do not secure.
(5) Pivot the damper to align rod end with hole in hinge pin.
NOTE:
Slotted style rod end using the locking key must be installed with
the key on the top side to prevent interference with the hinge pin.
See Figure 9-15.
(6) Install spacers on each side of rod end and slide rod end into hinge pin while
aligning spacers with hole.
(7) Install washer on 1/2 inch bolt and install bolt through hinge pin and rod end.
Install two washers and locknut on bolt.
(8) Torque 1/2 inch bolt to 450 to 500 in.-lbs/50.8 to 56.5 Nm while aligning cotter
pin hole. Install cotter pin.
(9)
Torque
inboard
damper
bolt to 190 in.-lbs/21.5 Nm.
(10) Install washer and locknut on center walking beam bolt. Torque nut and install
cotter pin.
I.
Main
Rotor
Hub
– Installation (See Figure 9-1)
(1) Locate the spline with phasing mark at top of main rotor shaft and mark it with a
black felt marker for alignment ease. Apply No-Lok anti-seize compound to the
rest of the rotor shaft splines.
(2) Using sling T-0011 on main rotor hub assembly, carefully lower hub onto main
rotor shaft while aligning the phasing marks on lower spline adaptor to phasing
mark of rotor shaft spline. Remove sling.
CAUTION: When hub installed, the rotor shaft spline phasing mark must be
located between upper spline adapter phasing marks. Check this
before installing mast nut and washer.
(3)
Install
mast
washer
with
chamfered side down toward splines.
(4) Install mast nut and torque to 400 ft-lbs/542.3 Nm using tool T-0048. (See
Figure 9-2.) Safety wire mast nut using 0.041 safety wire (three places).
UNCONTROLLED COPY WHEN DOWNLOADED OR PRINTED
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