Mooney M20R - Power Plant Circuits

MOONN
AIRCRAFT
CORPORATION MZOR
SERVICE
AND MAINTENANCE
MANUAL
2.
Pre-stall
Waming
Circuit. The
pre-stall wamll/lg (2)
Install
and
conned
new
annunciator
assem
hom has
a
high frequency
continuous
tone
that
sounds
My
leaving
front
panel
off.
(Set
switch
to
"CAL~.
when
airspeed drops
to
within 4.3
to
8.7 KIAS
aboye
(3)
Drain fuel
from
tanks
and
replace
with
un-
stalling speed.
A
vane
in the left
wing
leading edge
ad/u-
usable
fuel,
plus
2
1/2
gallons
in both tanks.
ates
the
pre-stall
waming
horn switch.
CThis
vane
jis
(4)
Tum
Master
Switch ON and
adjust
calibra-
made of
heat treated steel
and
any
attempt
tion
pots
to
position
where ’low fuel"
lamps just
turn
switch
operation point by
bending
the
vane
will
on
for left
and
right
tanks.
the
switch).
Refer
to
section
27-93-00
for
procedures.
(5)
Tum Master switch
OFF,
set
annunciator
’CAL" switch
to
’NORM"
position,
install annunciator
3.
High
and
Low
Vacuum
Warning
Circuit.
A
swach/in
front and
install
glareshield.
the
vacuum
system
controls
the
vacuum
warning
light
Q~n
the
annunciator
panel.
Vacuum
below 4.25 IN.
Hg.
(6)
Refuelaircraft.
causes
the
vacuum
waming
light
to
FLASH.
Vacuu/m
5. Aftemate Air
Light Waming
Circuit Annunciator
above 5.5
IN.
Hg.
trips
the
high-vacuum
switch
causi~g
Panel.
The
light
illuminates
on
the annunciator
panel
when
the
vacuum
warning
light
to
illuminate
steadily,
the
altemate air door has
opened
for
any
reason.
4. Low
Fuel
Warning
Circuit. The low fuel
indicators
6.
Hi/Low
Voltage Waming
Circuit Annunciator
will illuminate
when
a
minimum
of 2 1/2
gallons
usa~le
Panel.
Remove annunciator
top
cover.
Conned
a
volt-
meterto aircraft
bus.
Start
engine
and
increase RPM
un-
fuel remains in
either
left
or
right
hand tank. When it
following procedure
should be
used
to
set
the
’low
Lights.
Slowly
decrease
RPM while
monitoring voltage
comes
necessary
to
replace
the
annunciator
panel
til
flashing
’VOLTS"
light extinguishes. (This
should be
any
reason
otherthan
"low fuel"
warning
malfunction,
above 26.6
volts).
Add
load,
such
as
Pitot
Heat 6
Nav.
wamingcircuits.
The calibration
transfer standard
(I
until
light
begins
to
flash. This should
occur
between
P/N
9500324000)
is
required
for this
procedure.
26.6 6 26.4
volts.
Adjust
trim
pot
as
necessary
to
obtain
ers
can
be
ordered
through Mooney
Service
desired result.
through
any
Mooney
Service
Center.
NOTE
A.
Calibration
Procedures
using
I.A.I.,
PAN
may
be
necessary
to
adjust
trim
pot
to turn
out
9500324000.
light
at
26.5
volts
first.
Increase RPM.
until
light
(1)
Remove
glareshield,
disconned
plug
goes
out
and
note
voltage.
Decrease
RPM until
rear
of
annunciator,
remove
annunciator front
panel,
light
flashes
on
and
note
voltage.
Light
should
place
"Norm-Cal" switch
in
’CAL"
position.
come on
between
26.4
and
26.6
vohs.
(2)
Plug,
P/N
9500324000,
calibration
transfer
standard
to
rear
of old
annunciator
and
reconned
h~r-
2434´•00
POWER
PLANT CIRCUITS
ness
plug.
(3)
Tum
Master Switch ON and
tum
right
halt~d
i.
Starter-ignition
Circuit. The
starter-ignition
switch
has five
positions:
OFF,
R
(right),
L
(leff),
BOTH,
and
variable
resistor
on
1~-ansfer
standard
slowly
counter
cloo,k-
START.
In the OFF
position
both
magnetos
am
wise until
rght
"low
fuel"
light just
tums
on.
Of
necess~ly
grounded.
At
the R
position
the left
magneto
is
tum
variable resistor
doc~vise
to
extinguish
’low
fu$l"
grounded.
At
the
L
position
the
right
magneto
is
light). @o
not
adjust
annunciator calibration
screws).
Ra
grounded.
At
the
BOTH
position
both
magnetos
are
HOT
peat
for
left ’low fuel".
and
the
ignition
system
is
ON.
Turning
the
ignition
switch
(4)
Tum Master Switch OFF and
remove
oild
to start
and
pushing
IN,
closes the
starter
solenoid,
en-
annunciator
assembly
after disconnedion of
harne$s
gages
the
starter and allows the
impulse coupling
to
and
transfer standard unit.
automatically
retard
magneto
until the
engine
is also
at
hamess
plug.
Remove front
plate
and
legend
on
produce
the
spark
to
fire
the
engine.
After
engine
starts,
(5)
Install
new
annunciator and
connect its
retard
firing
position.
The
spring
action
of
the
impulse
bration
transfer
standard
to
annunciator
panel
coupling
is then
released
to
spin
the
rotating
magnet
and
annunciator
panel
to
expose
the
NORM-GAL
the
impulse
coupling fiyweights
do
not
engage
due
to
and the Leftand
Right
trim
potentiometers.
centrifugal
action. The
coupling
then
ads
as,
a
straight
must
be in ’CAL"
position).
drive
and the
magneto
fires
at
the
normal
firing position
(6) Adjust
left
and
right
annunciator fuel
calibrl~
of the
engine.
The
starter-ignition
switch
is
spring
loaded
tion
screws
(nd
the
adapter
variable
resistoris)
to
retum
from START
to
the BOTH
position,
when
re-
until ’low fuel"
lights just
tum ON.
(If
necessary
tum
a~
leased.
nundator calibration
screw
counter
clockwise
to
extih-
WARNING
guish
’low
fuel"
light).
Do
not tom
the
propeller
when the
magnetos
are
O
Remove calibration
transfer
standard,
removing
switch
wires
or
electrical
connectors.
All
not
grounded.
Ground the
magneto
points
before
conned
plug
to
annunciator
panel,
set
switch
"NORMAL170
position,
install
annunciator
front
pan;el
spark
plug
leads
can
be
removed
as
an
alternate
and install
glareshield.
safety
measure.
a.
Anemate
method
for
calibration
without
I.All.
CAUTION
unit.
Do
not
operate
starter
in
excess
of 15
seconds
or
If
calibration
transfer
standard,
P/N
9500324000,
is
nd
available
use
the
following
method
to
calibrate ’low
fu~l"
m-engage
starter
without
allowing
it time
to
cool.
warning:
(1)
Remove
glareshield
and
remove
annuncig-
tor
assembly.
24-34-00
REV.i0-98
Island Enterprises