Cessna T188C - Page 148

MODEL
188 & T188
SERIES SERVICE
MANUAL
NOTE
f. With bearing (6)
flush with end of housing
(12),
carefully
drill
bearing so the
drill will emerge
Relative
linear
movement
between
internal
from the
hole on the
opposite
side of
housing (12).
threaded
screw (9)
and bearing
(14) should
DO
NOT ENLARGE
HOLES IN
HOUSING.
be
0.004 to 0.010
inch at room
temperature.
g.
Press new groov
pins (10) into
the pin holes.
h.
Insert collar
(7), new O-ring
(13) and bearing
e.
Examine threaded
rod end
(15) and screw
(9) for
(14) into opposite
end of
housing (12).
damaged
threads or dirt particles that
may impair i. Complete
steps "f" and "g" for bearing
(14).
smooth
operation.
j. If a new
bearing
(16) is required,
a new
bearing
f. Check
sprocket
(5) for broken,
chipped
and/or
may be
pressed
into the
boss.
Be sure
force
bears
worn
teeth.
against
the outer race
of bearing.
g.
Check
bearing
(16) for
smoothness
of
operation.
k. Screw
the
threaded
rod
end (15)
into screw
(9).
h.
DO
NOT
attempt
to repair
damaged
or
worn
1.
Install
retaining
rings
(11),
if they
were
re-
parts of
the actuator
assembly.
Discard
all defective
moved.
items
and Install
new parts
during
reassembly.
m. Test
actuator
assembly
by
rotating
sprocket
(5)
with fingers while holding threaded rod end (15).
9-10.
REASSEMBLY.
(See figure
9-4.)
The
threaded
rod
end should
travel
in and
out smooth-
a. Always discard
the following items
and install ly, with
no indication of binding.
new parts
during
reassembly.
n. Reinstall
actuator
assembly
in accordance
with
1.
Groove Pins
(8 and
10)
paragraph
9-7.
2.
O-Ring
(13)
3. Nuts
(2).
9-11.
TRIM TAB
FREE
- PLAY
INSPECTION.
b.
During
reassembly,
lubricate
collars
(7)
a. Place
elevator
and
trim tab
in neutral
position
screw
(9) and
threaded
rod end
(15)
in accordance
and secure
from movement.
with Section
2.
b. Determine
maximum
amount
of allowable
free
c. Slip
collar
(7) and
bearing
(6)
on screw
(9).
play
using
formula
shown
in figure
9-2.
d.
Press
sprocket
(5) into
the
end of screw
(9),
c.
Using
moderate
hand
pressure
( up and
down),
align groove
pin holes and install new
groove pin (8). measure
free-play at trailing edge of
trim tab.
e. Insert
screw
(9), with
assembled
parts,
into
d.
If trim
tab
free-play
is
less than
maximum
allow-
housing
(12)
until
bearing
(6)
is flush
with
the
end
of
able,
the
system
is within
prescribed
limits.
housing.
e. If trim
tab free-play
is more
than
maximum
allowable, check the following items for looseness
NOTE
while
moving
trim
tab up
and down.
1. Check
push-pull
tube to trim
tab horn assem-
When
inserting
screw
(9) into
housing
(12),
bly
attachment
for
looseness.
locate
the
sprocket
(5) at
the end
of housing
2.
Check
push-pull
tube
to actuator
assembly
which
is farther
away from
the groove
for
threaded
rod
end attachment
for
looseness.
retaining
ring
(11).
3. Check
actuator
assembly
threaded
rod
end
for looseness in the actuator assembly.
* New
bearings
(6
and 14)
are not
pre-drilled
f. If
looseness
is apparent
while checking
steps
and
must
be drilled
on
assembly.
The
groove
e-l
and e-2,
repair
by
installing
new
parts.
pins
(10)
are
1/16
inch
in
diameter
and
require
g.
If looseness
is apparent
while
checking
step
a 1/16 (0. 0625) inch
drill
e-3, refer to paragraph
9-6 through 9-10.
HINGE
POINT
HINGE POINT
-r
TRAILING
EDGE
TRAILING
EDGE
Detail
E
TRIM TAB
- -
Detail A
1. Measure
chord length
at extreme inboard
end of
E FREE-PLAY
UP
trim tab
as shown
in
detail
A.
2.
Mulitiply chord
length by 0.025
to obtain maximum
* NEUTRAL
POSITION
allowable
free-play.
o FREE-PLAY
DOWN
3.
Measure free-play
at same
point on trim tab
that
A* TOTAL
FREE-PLAY
chord
length
was
measured.
4.
Total
free-play
must
not
exceed
maximum
allow-
able. Refer to detail B.
Figure 9-2. Trim Tab Free - Play Inspection
9-5