Piper Navajo PA-31 Service Manual page 674

PIPER NAVAJO SERVICE MANUAL
TABLE X-III. TROUBLESHOOTING CHART (PRESSURE SYSTEM)
Trouble Cause Remedy
Pressure drops ex-
tremely low with single
pump operation. (Note
position of red indica-
tor button of pressure
gauge. )
Manifold check valve
leaking.
Check operation of valve
and replace if nec-
essary.
During single engine
operation, red pres-
sure indicator button
remains retracted on
inoperative engine.
Leaking manifold check Check operation of
valve. valve and replace if
necessarv.
No pressure gauge in-
dication at instrument.
No pressure gauge in-
dication at instrument.
No pressure gauge in-
dication at the instru-
ment or source.
Pump inoperative. Dis
connected, broken or
restricted lines.
Hose from instrument
to gauge leaking or
restricted.
Faulty gauge. Mal-
functioning regulator
valve or pump.
Replace pump. Locate
trouble and correct.
Check all lines and
connections.
Check operation of in-
strument. If operation
is faulty, replace gauge.
If instrument is not
faulty, check operation
of pump and regulator
valve.
Reissued: 10/12/79 INSTRUMENTS
3E12