Altimeter Troubleshooting - Piper PA-24 Comanche Service Manual

PIPER COMANCHE SERVICE MANUAL
TABLE XI·V. ALT1METER
Trouble
Clue
Remedy
Excessive scale error.
Improper Qlibrarion adjust-
Replace instrUment.
menr,
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Excessive pointer Defective mecbanism.
Replace instrument.
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cm:illation.
High reading. Improptr venting.
Eliminate leak in static
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prt."l$ure system and check
aliJnment of airspeed tube.
Settl"' knob is hard to Wrona lubrication or lack
Replace instrument.
rum. of lubrication.
Inner reference marker OUt of Cftg2lement.
Replace insrrument.
fails to meve when
i
setting knob is rotated.
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Settlng knob
in
Krl:W Excessive vibrauon. Tightcn mstrument screw.
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loose or missing.
if lOOK. Replace in-
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suummt. if screw is
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missing.
i
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Cracked or loose cover Excessive vibration. Replace instrumcnt.
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glass.
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j
Dull or discolored
Age. Replace instNment.
lummous markings.
I Barometric scale and
Slippage of mating pam. Replace InstTUment.
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reference markers out
I
of synchronism.
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Barometric scale and
Drift in mechanism.
Reset pointers. refer to the
reference markers OUt
latest revision of AC 43. 13-I.
of synchronism with
pointers.
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REVISED: 4/10/81
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INSTRUMENTS
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