Troubleshooting (Altimeter) - Piper Dakota Maintenance Manual

CHART 3402. TROUBLESHOOTING (ALTIMETER)
Trouble
Excessive scale error
Excessive pointer oscil-
lation.
High or low reading.
Setting knob is hard to
turn.
Inner reference marker fails
to move when setting knob
is rotated.
Setting knob set screw
loose or missing.
Cracked or loose cover
glass.
Dull or discolored
markings.
Barometric scale and ref-
erence markers out of syn-
chronism.
Barometric scale and ref-
erence markers out of
sync with pointers.
Altimeter sticks at altitudc
or does not change with
chatlge of altitudc.
PIPER AIRCRAFT
PA-28-236
MAINTENANCE MANUAL
Cause
Improper calibration ad-
justment.
Defective mechanism.
Improper venting.
Wrong lubrication or lack of
lubrication.
Out of engagement.
Not tight when altimeter
was reset. .
Case gasket hardened.
Age.
Slippage of mating pans.
Drift in mechanism.
Water or restriction in
static line.
2D14
Remedy
Calibrate or replace
instrument.
Replace instrument.
Eliminate leak in static
pressure system and check
alignment of airspeed tube.
Replace instrument.
Replace instrument.
Tighten instrument screw,
if loose. Replace instrument,
if screw is missing.
Replace instrument.
Does not require repair.
Replace instrument.
Refer to the latest revision
of AC 43.13-1.
Remove static lines from all
instruments, blow line clear
from cockpit to pitot head.
34 - 12 - 00
Page 34 - 06
Reissued: August 1, 1986