Table of Contents
Advertisement
(e)
Install the
mounting screws
that
secure
the
false panel to the aircraft structure.
( f)
Install
the
plastic
placard
strip
over
switches
and
engine controls. Secure the fasteners
by
pushing
into
locking position.
5.6
INSTRUMENT
VACUUM SYSTEM
-
The vacuum
sys
tem
consists
of
two
engine-
driven vacuum pumps
(one
on each engine), an oil se-
parator in each engine accessory section, a s uction
relief
valve in each
wheel well,
a
filter behind Instru-
ment panel, a suction gage
on
instrument panel,
and
necessary interconnecting
tubing
and
hose.
It
powers
the gyro-controlled
flight
instruments.
5.6.1
Adjustment
of
Suction
Relief Valve
-
(a)
Loosen
locknut
and
turn
adjusting screw
counterclockwise
to
increase s uction, or clockwise to
decrease s uction.
(b)
Adjust suction
relief valve
to
draw 4.25 inches
of mercury at cruising
speed.
5.6.2
Removal
of
Vacuum
Pump -
(a)
Disconnect suction and discharge lines.
(b)
Remove
nuts from the
four
mounting
s
tuds.
(c)
Pull pump
out
and
off
engine
mounting pad.
NOTE
Before
installation
of
pump, make
s
ure lubri-
cation
holes in pump
flange
are
not
covered
by the
flange gasket.
5.6.3
Installation
of Vacuum Pump -
(a)
Place gasket in position
on
mounting studs.
(b)
Place pump
on engine mounting
pad.
(c)
Install and
tighten
nuts.
5.6.4
(a)
(b)
Removal of
Oil Separator
-
Disconnect
inlet,
outlet, and
oil
return
lines.
Remove
two bolts
from mounting
brackets.
Revised
1
Jun
e
1955
4
(c)
Lift
unit from mounting.
NOTE
Clean
oil separator In unleaded
gasoline
o
r
other suitable solvent and dry thoroughly
with
compressed air each 100 hour
inspection.
5.6.5
Installation of
Oil Separator
-
(a)
Place
unit In mounting bracket.
(b)
Install bolts
In
mounting
bracket and tighten.
(c)
Connect
inlet, outlet, and
oil
return
lines.
5.6.6
Removal
of Suction Relief
Valve
-
Disconnect lines at inlet and
outlet
elbows.
Unit
will fall free.
5.6.7
Installation of
Suction Relief Valve -
Connect lines
at inlet and
outlet
elbows.
5.6.8
Removal of Filter -
(a)
Disconnect
Instrument lines
at manifold.
(b)
Remove nuts fr om
the two mounting
bolts.
(c)
Remove filter bowl
to
clean
or replace
filter
element.
NOTE
The filter should be
cleaned every fifty
hours.
To clean element blow
air through element
in
the direction
opposite
normal flow
.
Care
should
be taken not to blow
air into
element
at right
angles,
as
this will
tend
t
o clog
dust
in element.
Tilt air hose at approximately
forty-five
de-
grees. After dust has been blown
from ele-
ment, wash in alcohol, then dry with
compress-
ed
air.
5.6.9
(a)
(b)
(c)
Installation
of
Filter -
Place unit
on
mounting bracket.
Install
nuts
on the two m ounting
bolts.
Connect instrument lines
at
manifold.
Advertisement
Table of Contents
