ENSTROM F-28F/280F SERIES MAINTENANCE
MANUAL
Rev.
7
MM-9-17
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
40NB
C20
-
52YZP
7
Bearing
O.D. 3.2492 t
o
3.2500
I.D. 2.4993 to 2.5000
Ratcheting or
roughness
No Tole
ra
nce
Allowed
No Tole
ra
nce
Allowed
Non
e Allowe
d
Not Repairabl
e
Not Repairabl
e
Not Repairabl
e
Repl
ace Bearing
Repl
ace Bearing
Repl
ace Bearing
28-1
426
1
8
Spacer
Length 3.061
to 3.062
Ends pa
rall
el
-.001
Within .0012 FIM
Not Repairabl
e
Not Repairabl
e
Repl
ace Spacer
Repl
ace Spacer
32NB
C20
-
44YZP
9
Bearing
O.D. 2.7494 t
o
2.7500
I.D. 1.9993 to 2.0000
Ratcheting or
roughness
No Tole
ra
nce
Allowed
No Tole
ra
nce
Allowed
Non
e Allowe
d
Not Repairabl
e
Not Repairabl
e
Not Repairabl
e
Repl
ace Bearing
Repl
ace Bearing
Repl
ace Bearing
28-1
431
3
11
DU
Wa
she
r
Thickne
s
s .090 to.093
-.
003
Not Re
pairabl
e
Repl
ace Wa
sher
28-1
427
9
13
Blade Gri
p
Blade retention bolt
bore
Dia. .875 to .876
Larg
e bea
rin
g bore
Dia.
3.2512 to 3.2522
Small beari
ng
bore Di
a.
2.7511 to 2.7519
Thru b
ore
Dia
. 1.5145
to 1.5165
Dra
g link e
ar
width .745
to .747
+
.0
0
05
+
.0
0
18
+
.0
0
11
+
.0
0
15
-.001
Not Repairabl
e
Not Repairabl
e
Not Repairabl
e
Not Repairabl
e
Not Repairabl
e
Repl
ace Blad
e Grip
Repl
ace Blad
e Grip
Repl
ace Blad
e Grip
Repl
ace Blad
e Grip
Repl
ace Blad
e Grip
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