Mooney M20B - Page 85

INSTRUMENT
TROUSLESHOOTING
(Con~inued)
TIZOZTBLE
CAUSE
I
REMEDY
ALTIMETER
Excess
scale
c~ror..
I
Improper
calibration
Replace
instnunent.
;idjustment.
Excessive
pointer
De~ective
mechanism
Replace
instnunent.
oscillation.
Highreading.
I
Improperwnting.
Eliminate leak
in static
pressure
sys-
ten
and
check
alignment
of
air-speed
~uh.
Setting
knob
is
hard
to
Wrong
lubrication
or
lack
i
Replace
instrument.
turn:
´•´•´•loflubrication.
Inner
reference
marker Out
of
engagement.
Replaceinstrument.
fails
~to
move
when
setting
knob
is rotated.
Setting
knob setscrew
Excessive
vibration.
Tighten
instrument
screw,
if
loose.
loose
or
missing.
I
Replace instrument,
if
screw
is
missing.
Cracked
or
loose
cover
Excessive
vibration.
Replace
instrument
glass.
Dull
or
discolored
lumi-
I
Age.
._
I
Replace
instrument.
nous
markings.
Barometric scale
and ref-
Shift in
mechanism.
Reset
pointers.
~nence
markers
are
out
of
synchronism
with
pointers
Barometric
scale and
ref-
Slippage
of
mating
parts. Replace
instrument.
ernce
markers
out
of
syn-
chronisn
AIRSPEED
I~NDICATOR
Pointers
of
static
instru-
Leak
in instrument
case
Check
for
leak
an;i
seal
ments
do
not
indicate
I
or
in
pitot
lines.
properly.
Pointer of instrument
Leak
in
instrument
case
Check
for
leak and
seal.
oscillates.
or
in
pitot
biles.
HEATED
PITOT
TUBE
(IF
USED)
Tubedoes
no’
heat
or
clear
Switch circuit
breaker
Replace
or
reset
of
ice w;th swich ON.
out.
´•e
OLDWILLWAYNE