Description - Cessna 1969-1976 172 Series Service Manual

SECTION 15
INSTRUMENTS AND INSTRUMENT SYSTEMS
TABLE OF CONTENTS Page
INSTRUMENTS AND INSTRUMENT SYSTEMS
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15-1
General
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15 -1
Instrument Panel
. . . . . . . . . . . .
15-3
De scription
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15 -3
RemovalandInstallation
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15-3
Shock-Mounts
. . . . . . . . . . .
15-3
Instruments
. . . . . . . . . . . .
15-3
Removal
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15 . 3
Installation
. . . . . . . . . .
15-3
Pitot and Static Systems
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15-3
Description
. . . . . . . . . . . .
15-3
Maintenance
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15-3
Static P r e s s u r e System Inspection
and Leakage Test
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15-3
Pitot System Inspection and
Leakage Test
. . . . . . . . . .
15-5
Blowing Out Lines
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15-5
Components
. . . . . . . . . . .
15 -5
Removal and Installation of
Trouble Shooting . Pitot Static
System
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15-6
True AirspeedIndicator
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15-6
Trouble Shooting
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15-6
Trouble Shooting -Altimeter
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15-8
Trouble Shooting . Vertical Speed
Indicator
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15 -8
Trouble Shooting . Pitot Tube Heater
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15-9
Vacuum System
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15-9
Description
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15-9
Trouble Shooting
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.1 5.11
Trouble Shooting - G y r o s
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.1 5.11
Trouble Shooting . Vacuum Pump
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.1 5.15
Removal and Installation of
Components
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15 -1 5
Pitot Tube Alignment
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15-9
15.1
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INSTRUMENTS AND INSTRUMENT SYSTEMS
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15.2
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GENERAL
.
This section describes typical
instrument installations and their respective opera-
ting systems
.
Emphasis is placed on trouble shoot-
ing and corrective measures only
.
It does NOT deal
with specific instrument r e p a i r s since this usually
requires special equipment and data and should be
handled by instrument specialists
.
Regulations require malfunctioning instruments be sent
t o an approved instrument overhaul and repair station
or returned to manufacturer for servicing
.
Our con-
c e r n here is with preventive maintenance on various
instrument systems and correction of system faults
which result in instrument malfunctions
.
The des-
criptive material, maintenance and trouble shooting
Federal Aviation
Cleaning
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15 . 15
Vacuum Relief Valve Adjustment
. . .
. l 5.15
Engine Indicators
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. l
5.16
Tachometer
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15 -16
Description
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15 -1 6
Oil P r e s s u r e Gage
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.1 5.16
Description
. . . . . . . . . .
15 -1 6
Trouble Shooting
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.1 5.16
Oil Temperature gage
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. l 5.17
Description
. . . . . . . . . .
15 -17
Carburetor Air Temperature Gage
.
.1 5.17
Description
. . . . . . . . .
.1 5.17
Trouble Shooting
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.1 5.17
Fuel Quantity Indicating System
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. l
5.18
I
Description
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15.18
Removal and Installation
.
.
.1 5.18
Trouble Shooting
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15.19
Transmitter Calibration
. . .
.1 5.19
Hour meter
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15 -19
Description
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15 -19
Magnetic Compass
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. l 5.20
Description
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15.20
Stall Warning System
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.1 5.20
Description
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15.20
Turn Coordinator
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15 -21
Description
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15.21
Trouble Shooting
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.1 5.21
Turn-and-Slip Indicator
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15.22
Description
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.1 5.22
Trouble Shooting
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. l 5.22
Wing Leveler
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. l 5.25
Description
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.1 5.25
Rigging
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.1 5.25
information in this section is intended to help the
mechanic determine malfunctions and correct them.
up to the defective instrument itself. a t which point
a n instrument technician should be called in
.
Some
instruments. such as fuel quantity and oil pressure
gages.
are s o
simple and inexpensive. r e p a i r s usu-
ally will be more costly than
a
new instrument
.
On
the other hand. aneroid and gyro instruments usu-
ally a r e well worth repairing
.
The words "replace
instrumentvT in the text. therefore. should be taken
only in the sense of physical replacement in aircraft
.
Whether replacement is to be with a
new instrument.
a n exchange one. or original instrument is to be
repaired must be decided on basis of individual c i r -
cumstance
s
.
Change 1
15-1