ENSTROM F-28F/280F SERIES MAINTENANCE
MANUAL
Rev.
7
MM-9-18
Aug
22/16
Table 9-2. Retention Assembly
–
Inspection
P/N Figure
9-8
Item #
Part Name
Inspection*
Serviceable Limi
ts*
Repair Limit
s
Repair or Action
28-1
427
9
13
Blade Gri
p (Cont'd)
Thre
ad
s (cro
ssed or
missi
ng
)
Nicks, scrat
c
hes, or
c
o
rr
os
ion
Cra
c
ks
Non
e Allowe
d
Non
e Allowe
d
Non
e Allowe
d
Not Repairabl
e
.010 deep
Not Repairabl
e
Repl
ace Blad
e Grip
Blend and p
ol
ish out
smooth
Repl
ace Blad
e Grip
28-1
432
0-1
2,
-15
14
Lamiflex
Bearin
g
Thick
n
ess
.770-.79
0
External to internal tab
angle 12° (-12)
External to internal tab
angle 15° (-15)
Colum
n for separations
(See Note)
±1/2°
±1/2°
N
o
ne allowed
Not repairabl
e
Not repairabl
e
Not repairabl
e
Not repairabl
e
Repl
ace lamiflex
Repl
ace lamiflex
Repl
ace lamiflex
Repl
ace lamiflex
28-1
433
5
16
Nut
Thrust face for flatness
Thre
ad
s (roll
ed or
missi
ng
)
.0015
Non
e Allowe
d
Not Repairabl
e
Not Repairabl
e
Repl
ace Nut
Repl
ace Nut
28-1
400
7
19
Blade Rete
ntion Bolt
O.D. .8738 to
.8745
-.0002
Not Repairabl
e
Repl
ace Bolt
Note:
Lamiflex bea
ring
s that are found swe
lled from grease co
ntam
ination sh
oul
d be cl
ea
ne
d with denat
ured al
co
hol
and che
c
ke
d f
or
delamination.
If the b
e
a
rin
g is
swelled
b
e
y
ond the lim
its (.790” thi
c
k), they may
still be
servi
ceable
if they
can be reinstall
ed i
n a
c
co
rdan
ce
with para. 9-4 and do not cause binding
in the control
s
.
Any bea
ring t
hat sho
w
s ev
iden
ce
of bul
ging
aro
und
the o
uter
circumfere
nce of
the el
astom
er
seg
m
ent
s, exce
ssive a
x
ial swelling,
vis
u
al
delamin
ation
of the segme
nts or the ex
pulsi
on of shi
m
fragment
s on the outsi
d
e diamet
e
r, should be
repl
ace
d
by an airwo
rthy bea
ri
ng
prior to the next flight.
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