Cessna T188C - Butterfly Valve Adjustment

MODEL
188
&
T188
SERIES
SERVICE
MANUAL
Detail
A
16
10
(Showing
Valve
MO '^r--B~
Positioning)
^9^.^~
C
~Chemical
Flow j To Boom
15
8,
1
1
13
3
i
18
Valve
Open
1 13
4j
ATo
(Spray
Position)
6 16
4 5 5 Chemical _
3 \
18
21
>
1.
Bolt
1 2. Coupler Adapter
; ~\ 'Ss ' ~ 3. o-ring 8 Valve Closed
4.
Shim
(Recirculate
Position)
\5. Packing
14. Seal
Attaching Screw
6.
Insert
15.
Hose
Adaptor
-
'7. Hopper Adaptor
16. Suck
Back Adjustment
Screw
8.
Butterfly
Valve
17.
Valve
Body
9. Cap
18. Grease
Fitting
19
10.
Control
Arm
(Manual)
19.
Dust
Cap
11. Butterfly
Halves
20.
Insert
Land
12.
Seal Retainer
21
Shaft
13.
Seal
Figure
19-29.
Manual
Butterfly
Spray
Valve
4.
Visually
inspect
shalt-to-land
seal
for
a snug
m.
Using
a thickness
gage,
measure
gap
between
fit.
If a 0.001-inch
shim
can be
slid between
shaft
each
adapter
(2)
and (15)
and valve
body
(17).
(21)
and land
(20), excessive
leakage
will result.
n. Subtract
0.010-inch
from measurements
obtained
5. Reinstall
or replace
insert
as required.
in
step "m",
and
install
shims equal
to
that number
g. Position
valve body
(17) with
hopper adapter
(7)
(1608075-1
shims
are 0.014-inch
and
1608075-2
shims
away from
you, and
the suck-back
adjus
tment screw
are
0. 005-inch.
)
(16) to
your right.
o. Reinstall
0-rings
(3) and
adapters
(2) and (15).
h. Slide
insert (6)
into valve body
(17), so that
p. Install cap
(9) and control
arm (10).
straight
land
(20) on the
inside of
insert is
toward
q.
Reinstall and
tighten
bolts and washers
attaching
you, and curved land is pointing away and to the adapters (2) and (15).
right. Shaft
holes in insert
should be aligned
verti-
r. Equally
tighten bolts attaching
adapters
to proper
cally in valve
body (17), and
with the lower
bearing.
torque values.
Refer to chart
in Section 2 of
this
i.
Carefully slide shaft
(21) through insert
(6),
manual.
and into
lower
bearing.
s. Attach
hopper
adapter
(7)
to aircraft
hopper,
j. Install
butterfly
seal
assemblies
into the
shaft.
after
lubricating
fitting
with MIL-G-81322A
general
Coat
screws
and slot
edge
of
seals
with
Loctite
purpose
grease.
Sealant
Part
Number
59231,
if required,
prior
to
t. Connect
coupling
and
hose
to respective
adapters.
assembly.
Check
system
after
curing
time
of sealant
has
lapsed.
k. Remove
O-rings
(3) and
shims
(4) from
adapters
(2)
and (15),
and
slide
into
valve
body (17),
with
pack-
: 19-89.
ADJUSTMENT.
If "suck-back"
adjustment
ings
(5) in
place.
is required
due
to nozzle
"drip",
an adjustment
1.
Stand
valve
on
one
end
and
place
a 10-lb.
weight
screw
(See
figure
19-27)
is
incorporated
on the
on the
top end.
aft
side of
the
control
valve.
Screwing
in
the
adjust-
19-63