Mooney M20K - General; Indicating; Fuel Flow System - General System Description; Panel Mounted Instrument

SERVICE
AND
MAINTENANCE
MANUAL
MOONEY
AIRCRAFT
CORPORATION
M20K
73-00-00
-GENERAL
continuous
consumption
or
78
GAUHR
Intermittent
consumption.
CTake
off
power).
The
engine
and
its
accessories are
certificated
under
Teledyne
Continental
Motors
CTCM)
Type
Certificate.
7331-01
-PANEL
MOUNTED
INSTRUMENT
Refer
to
TCM
Operators
or
Ovemaul
Manual
for
The
panel
mounted
instrument
contains
all
system
specific
instructions.
electronics
and
may
be
divided
into
groups.
73-3090
-INDICATING
1.
FT-101
OHOSKINS)
SYSTEM
A.
DISPLAY
The
display
uses
one
mini
lamp
and
S/N 25-0001
thru
25-0612
have
an
analog
readout
four
seven
segment
incandescent
digits
that
are
fully
style
fuel
flow
indicator
which
receives
its
signal
from
a
sunlight
readable
and
dim
automatically
dun~ng
night
transducer
(Mooney
SI
M20-48
descn’bes
adjustment
,,d I,,
light
flight
conditions.
of
Aerosonic
analog
F/F
gauge).
SIN
250001
through
S/N
25-0171
originally
had
a
pressure
transducer
B.
MICROPROCESSOR
The
microprocessor
installed.
SI
M20-49
described
a
recommended
contains
a
crystal
controlled
oscillator
that
controls
all
modification
to
a
turbine
type
transducer
and
matching
timing
and
computing
functions
for
precise
fuel flow
indicator.
This
turbine
transducer
has
been
the
and
totalizing
computations.
production
configuration
since
S/N
25-0172,
however,
C.
POWER
SUPPLY
The
power
supply
is
a
high
the
indicators
have
varied.
S/N
25-0613
3
ON,
the
speed
switching
regulator
type
for
optimum
efficiency
standard
indicator
has
been
a
digital
readout
type.
and
the
lowest
possible power
drain
on
the
aircraft
Digital
indicators
have
been
optional
equipment
for
all
electrical
system.
aircraft
up
to
S/N
25-0613.
continuously
D.
MEMORY-
the
microprocessor
All
aircraft
should now
have
the
turbine
transducer
stores
and
updates
the
totafu~ed
fuel
quantity
in
a
Installed
per
SI M20-49.
random
access
memory
chip.
The
Total
Fuel
Used
quantity
is
retained
dun~ng
aircraft
shut
down
by
73-31-00
FUEL
FLOW
SYSTEM
GENERAL
connecting
the
memory
wire to
the
aircraft
battery
SYSTEM
DESCRIPTION
through
a
memory
switch.
The
drain
on
the
aircraft
battery
is
small
due to
the
low
power
MOS
memory
The
Fuel
Flow
Totalizer
system,
utilizes
the
latest
in
chip
which
uses
only
0.7
milliamps
at
12
VDC
(13
microcomputer
technology
products.
The
fuel
flow
milliamps
at
24
VDC,
FT1OIA).
system
is
designed
to
maximize
the
efficiency
of fuel
system
management
by
displaying
the
fuel
E.
INTERNAL
SWTTCH
ARRANGEMENT
The
consumption
rate
(fuel
flow)
of the
engine
and the
programming
switch
block
(see
Figure
73-2)
located
precise
amount
of fuel
the
engine
has
consumed.
This
inside
the
PT-101
panel
mounted
unit
has
several
information
may
be
displayed
in
one
of the
following
arrangements
to
change
data
readout
if
desired.
formats,
US
Gallons,
Pounds,
Liters
or
Imperial
Switches
S1 and
S2
(see
Figure
73-1)
should
not
be
Gallons
(Alcor)
depending
on
switch
or
contact
changed
unless
the
transducer
"K"
factor
of
a
arrangement,
see
(Figure
73-1
and
73-2).
replacement
transducer
differs
from
the
on’ginal
unit’s
"K" factor
(see
Section
73-31-02,
3,
for
"K"
factor
The
system
consists
of
a
panel
mounted
instrument
description).
and
a
fuel
flow
transducer
which
is
installed
in
the
Switches
S3
thru
S7
can
be
positioned
in
various
aircraft
engine
fuel
line,
arrangements
to
change
full
flow
readout
to
gallons,
The
system
is
designed
for
use
in
all
single
engine
fuel
pounds
or
liters
as
the
situation
may
require,
(see
injected
aircraft
having
no
more
than
60
GALRHR
Figure
73-1).
FT-1O1SWITCH
ARRANGEMENT/
FT-~101
TRUTH
FIGURE
73,1
K-FACTOR
SWITCH
ARRANGEMENT
S1
S2
L
ON
ON
M
ON
OFF
H
OFF
ON
HH
OFF
OFF
FUNCTION
SWITCH
ARRANGEMENT
S3
S4
S5
S6
S7
GALLONS
ON
OFF
OFF
NA
NA
POUNDS
OFF
ON
OFF
NA
NA
LITERS
OFF
OFF
ON
OFF
NA
73-00-00
OLDWILLWAYNE