Piper cherokee WARRIOR - SYSTEM FAILURE PROCEDURES; Alternator Failure and Engine Roughness

CHEROKEE
WAR.RIOR
ALTERNATOR
FAILURE
Loss
of alternator
output
is detected
through a
zero readhg
on
the ammeter.
Before
executing
the following
procedure,
insure
that the
reading
is
zero and not
merely
low
by
actuating
an electrically
powered
device, such
as the
landing
light.
If no increase
in the
ammeter
reading
is noted, alternator
failure can
be assumed.
l.
Reduce electrical
load.
2.
Alternator
Circuit
Breakers
-
Check
3.
"Alt"
Switch
-
Off
(for
I second), then
On
If the
ammeter
continues
to
indicate
no output, or
alternator
will not
stay
reset, turn
off
"Alt"
switch,
maintain
minimum
electrical
load, and
land as soon
as
practical.
All electrical
power
is being supplied
by the
battery.
ENGINE
ROUGHNESS
Engine roughness
is usually
due to carburetor
icing
which is indicated
by
a drop
in
RPM,
and may
be accompanied
by a
slight loss of airspeed
or altitude.
If
too much
ice
is allowed
to
accumulate,
restoration
of
full
power
may
not be
possiblel
therefore,
prompt
action
is required.
l. Carburetor
heat
-
on
(See
Note). RPM
will decrease
slightly
and
roughness
will
increase.
Wait for a decrease
in engine roughness
or
an increase
in
RPM,
indicating
ice
removal.
If no change
in approximately
one minute,
return
carburetor
heat
to OFF.
If
the engine
is still
rough,
try steps below.
a.
Mixture
-
Adjust
for
maximum
smoothness.
Engine
will run
rough
if too
rich or
too
lean.
b.
Electric
Fuel
Pump
-
On
c.
Fuel Selector
-
Change
to other tank
to see
if
fuel
contamination
is the
problem.
d.
Engine
Gauges
-
Check
for abnormal
readings.
If any
gauge
readings
are
abnormal,
proceed
accordingly.
e.
Magneto
Switch
-
"L" then
"R"
then
back to
"BOTH."
If operation
is
satisfactory
on either
magneto,
proceed
on
that
magneto
at reduced
power,
with
mixture
full rich, to a
landing at
the first available
airport.
If roughness
persists,
prepare
for a
precautionary
landing
at
pilot's
discretion.
NOTE
Partial carburetor
heat may cause
partial
melting
of ice
which
will refreeze
in the
intake system;
therefore
when
using
carburetor
heat, always
use full
heat and
when ice
is removed
retum
to the
full
cold
position.
EMERGENCY
PROCEDURES
REVISED:
JANUARY
25, 197
444