Cessna 150M - Instruments and Instrument Systems

SECTION 15
INSTRUMENTS AND INSTRUMENT SYSTEMS
TABLE OF CONTENTS
INSTRUMENTS
AND INSTRUMENT SYSTEMS
General .....
Instrument Panel. . . . . .
Description . . . . . .
Removal and Installation
Shock-Mounts
Instruments . .
Removal
Installation
Pitot and Static Systems
Description . . . .
Maintenance . . . .
Static Pressure System Inspection
and Leakage Test ....
Pitot System Inspection and
Leakage Te st . . . . .
Blowing
Out Lines . . . .
Removal and Installation of Com-
ponents .......... .
Trouble Shooting-Pitot Static System
True Airspeed Indicator. .
Trouble Shooting . . . . .
Trouble Shooting-Altimeter . .
Trouble Shooting-Vertical Speed
Indicator . . . . . . . . .
Trouble Shooting-Pitot Tube Heater.
Pitot Tube Alignment
Vacuum System
Description . . . .
Trouble Shooting . .
Trouble Shooting-Gyros.
Trouble Shooting-Vacuum Pump
Removal and Installation of
Components . . . . . . . .
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15-1.
INSTRUMENTS AND INSTRUMENT SYSTEMS.
15-2. 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 repairs since this usually
requires special equipment and data and should be
handled by instrument specialists. Federal Aviation
Regulations require malfunctioning instruments be sent
to an approved instrument overhaul and repair station
or returned to manufacturer for servicing. Our con-
cern 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
Cleaning . .15-14
Vacuum Relief Valve Adjustment. .15-14
Engine Indicators .15-14
Tachometer .15-14
Description
.15-14
Oil Pressure Gage
.15-15
Description
.15-15
Trouble Shooting .15-15
Oil Temperature Gage
.15-
15
1
Description
.15-15
Fuel Quantity Indicating System
.15-16
Description
.15-16.
Removal and Installation
.15-16
Trouble Shooting .
.15-16
Transmitter Calibration. .15-17
Hourmeter .15-17
Description .15-17
Magnetic Compass .15-17
Description .15-17
Accelerometer
.15-18
Description .15-18
Stall Warning System .15-18
Description .15-18
Turn-and-Slip Indicator. .15-19
Description .15-19
Trouble Shooting
.15-19
Turn Coordinator.
.15-20
Description .15-20
Trouble Shooting .15-20
Electric Clock .15-22
Description .15-22
Wing Leveler .15-22
Description .15-22
Rigging .15-22
information in this section is intended to help the
mechanic determine malfunctions and correct them,
up to the defective instrument itself, at which point
an instrument technician should be called in. Some
instruments, such as fuel quantity and oil pressure
gages, are so Simple and inexpensive, repairs usu-
ally will be more costly than a new instrument. On
the other hand, aneroid and gyro instruments usu-
ally are well worth repairing. The words "replace
instrument" 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,
an exchange one, or original instrument is to be
repaired must be decided on basis of individual cir-
cumstances.
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