Piper Cherokee Six - Page 491

PIPER
CHEROKEE
SIX
SERVICE
MANUAL
TABLE
IX-I.
VACUUM
SYSTEM
(cont)
Trouble
High
system
pressure.
Cause
Vacuum
regulator
in-
correctly
adjusted.
Remedy
Adjust
regulator.
Vacuum
regulator
sticking
or
dirty
screen.
Clean
and
check
opera-
tion
of
regulator.
Regulator
cannot
be
adjusted
to
produce
correct
pressure.
Lines
leaking.
Check
lines
and
fittings.
Vacuum
pump
mal-
functioning.
Replace
pump.
Vacuum
correct
on
ground
but
will
not
maintain
pressure
at
altitude.
Vacuum
pump
mal-
functioning.
Replace
pump.
Regulator
sticky.
Clean
regulator.
Vacuum
correct
but
pilot
reports
pressure
erratic
or
shows
complete
loss
in
flight.
Regulator
sticky.
Clean
regulator.
Oil
in
pump
due
to
leaky
engine
seal
or
cleaning
fluid
blown
into
pump
while
cleaning
engine.
Replace
pump.
Pressure
can
only
be
maintained
at
full
throttle
on
ground.
Leak
in
system.
Repair
or
replace
lines.
Worn
pump.
Stuck
regulator.
Replace
pump.
Clean
or
replace
regulator.
I
INSTRUMENTS
Revised:
8/7/74
2J23