Cessna T188C - Adjustment; Description; Removal; Removal and Installation and

MODEL
188
& T188
SERIES
SERVICE
MANUAL
g. Tighten
packing nut
only enough
so that linkage
NOTE
works freely when rotated
by handle (18).
h.
Check that DEXRON
type automatic
transmission
If
the adjustment
screw is not disturbed,
fluid
is to FULL mark
on dipstick
in reservoir and
suction adjustment
should not
be required.
pressurize
to 15
psi.
19-79.
REASSEMBLY.
(BALL
TYPE
VALVES)
i. Install
side panels
on left
side of aircraft,
aft of
(See
figure 19-27.
firewall.
a.
Install
ball
(26), packings
(27). support
assembly
19-72. BOOM PRESSURE VALVE CONTROL LINK- (29) with packing (28) and lever (30).
AGE. (See figure 19-21, sheet
12.)
b. Check ball (26) and seals
(23), (35) and (38) fit
as follows:
19-73.
DESCRIPTION.
Beginning
with 18801683,
a 1.
Install adaptor
(21), seal (23).
adaptor (33)
two-part,
solid shaft linkage is employed
to control and
seal (35) less packings, bolts
and washers.
the boom pressure valve. The
control handle is lo-
2. Applying equal forces
against adaptors (21)
cated below the left side of the instrument panel, and (33), measure gaps between adaptors (21) and (33)
The valve is attached to a bracket which is welded to and valve body (25).
the structural
tubing on the left side of the
aircraft, 3. Install
shims (24) and (36) as required
to a
outboard
of the hopper,
thickness
of .002-inch less than each
gap measure-
ment.
19-74. REMOVAL, INSTALLATION AND RIGGING. 4. Install side cover (40) and seal (37).
Refer
to paragraph 19-70, steps "d",
"e" and "g", 5.
During assembly, for measuring
gap between
and paragraph 19-71, steps
"c" thru "g" and "i".
valve body and two adapters, set
valve assembly up-
right, with hose adapter down on flat surface and
NOTE
cam-lock adapter up.
Place a 5 to 6 pound weight
on
top to give "equal forces" for seal-to-bail seating.
If universal
joints (14) were disconnected
or
then measure gap.
removed, pins (13) will have to be safety 6. Install shims (38) as required to a thickness
wired, and universal joints
will have to be of
approximately .002-inch less than
the gap measure-
wrapped with three layers of Polyken 230 or ment.
Polyken 231, (Kendall-Polyken Division, c. Disassemble components and install packings
Chicago, Illinois) or Tuck 92T, (Technical (22), (34) and (39).
Tape
Corp., Shawnee
Mission, Kansas).
d. Assemble
all components
and install
attaching
Also, if
spools (16) were
removed,
pins (13)
bolts
and washers.
will
have to
be safety
wired.
19-75. MANUAL CONTROL
VALVE.
SHIM CHART
19-76. DESCRIPTION. A three-way control valve is SIZE PART NO. THICKNESS
installed
between the pump,
the hopper
and the noz-
LARGE
1608075-1
005
zles. The
valve is controlled
by
the spray
valve con-
1608075-3
.005
trol
lever in the cockpit. This valve
permits a by-
LARGE 1608075-2
014
pass
for pressure control
and also
provides recircu-
SMALL
1608075-4
014
lation
through
the hopper
for
a more
consistant
mix-
ture of the spray material. Also incorporated into
the control valve is a bleed-back valve to relieve
boom pressure after the
control valve is closed to
19-80. ADJUSTMENT.
If suck-back adjustment is
prevent
nozzle "drip".
required
due to nozzle "drip", an adjustment
screw
is incorporated
on the aft side
of the control
valve.
19-77. REMOVAL AND INSTALLATION. Screwing in on the adjustment screw decreases suc-
tion. Unscrewing
the
adjustment screw
will increase
NOTE
the suction. Screw
should be "backed-out
until noz-
zles stop
"dripping".
Back adjustment
screw out se-
lf the
adjustment screw is not disturbed,
ven turns
from CLOSED position for maximum
"suck-
suction adjustment should not be required. back." (See figure 19-27, Item 32.)
a. Completely dram
hopper.
19-81. ELECTRIC SPRAY
VALVE ASSEMBLY.
b. Disconnect
control
rod at valve
control lever.
c.
Disconnect
hose
coupler
at forward
end of
valve.
CAUTION
d. Remove hose and clamps at aft end of valve.
e. Remove bolts
attaching valve
to adaptor
at gate
An electric
motor dynamic
braking system
box
and remove
gasket or seal.
is provided
on the Cessna
valve through
a
f. Reverse
preceding
steps
for valve
installation.
series
of
relay and
limit
switch
circuitry
in
the
aircraft.
DO
NOT
electrically
operate
19-78. DISASSEMBLY.
(BALL TYPE VALVES)
valve assembly
except through this cir-
See
figure
19-27
for
valve
disassembly.
cuitry.
19-58