TABLE X-I. VACUUM SYSTEM
Trouble
Cause
Remedy
No vacuum gauge indica-
Filter clogged or dirty
Clean or replace filter.
tion at instrument.
Line from gyro to filter
Check line.
restricted.
No vacuum gauge indica-
Faulty gauge or mal-
Replace gauge. Replace
tion at instrument or
functioning pump.
pump.
source.
Low vacuum system
Filter dirty.
Clean or replace filter.
pressure.
Vacuum regulator valve
Adjust regulator valve in accordance
incorrectly adjusted.
with adjustments in this section.
Line from gyros to
Repair line.
filter restricted.
Line from pump to gyros
Check all lines and
leaking.
fittings.
Normal pressure indication
Faulty instrument.
Replace instrument.
but sluggish operation
of instruments.
High system pressure.
Vacuum regulator
Adjust regulator.
incorrectly adjusted.
Vacuum regulator
Clean and check opera-
sticking or dirty screen.
tion of regulator.
Regulator cannot be
Lines leaking.
Check lines and fittings.
adjusted to produce
correct pressure.
Vacuum pump mal-
Replace pump
functioning.
Vacuum correct on
Vacuum pump mal-
Replace pump.
ground but will not
functioning
maintain pressure at
altitude.
Regulator sticky.
Clean regulator.
PIPER AIRCRAFT
PA-28-161 CADET
AIRPLANE MAINTENANCE MANUAL
Issued: FEBRUARY. 28, 1989
I N S T R U M E N T
2B13