Mooney M20TN, Service And Maintenance Manual

Page: 341 / 1169

MOONEY AVIATION COMPANY, INC.
M20TN SERVICE & MAINTENANCE MANUAL
Date
2006
Rev Date
Page 7
34--12--01 -- RATE--OF--CLIMB INDICATOR TROUBLESHOOTING (VERTICAL SPEED INDICATOR) (TRADI-
TIONAL)
TROUBLE PROBABLE CAUSE REMEDY
Pointer does not set on zero. Aging of diaphragm. Turn setting screw to reset pointer at
zero. Tap instrument while resetting.
Pointer fails to respond. Obstruction in static line. (Includes
water)
Disconnect static line from instru-
ments. Apply low pressure air
(10--25 PSI max.) to instrument end
of static line. Check both static ports
for air flow. Depress static drain
valve and check for water. Keep de-
pressed until air is free of moisture.
Reconnect static line to instruments
and leak check.
Pointer oscillates.
Leak(s) in static line. Disconnect all instruments con-
nected to static line. Check individu-
al instruments and test installation
for leaks.
Defective mechanism. Replace instrument.
34--13--00 -- ALTIMETER (TRADITIONAL)
The traditional altimeter operates by absolute pressure
and converts barometric pressure to altitude; reading is
in feet above mean sea level (MSL). The altimeter has a
fixed dial with three pointers to indicate hundreds, thou-
sands, and tens of thousands of feet. Barometric pres-
sure is sensed through static vents. A knob adjusts a
movable dial behind a small window (Kollsman) in face
of main dial to indicate local barometric pressure. This
corrects altimeter reading for prevailing conditions.
The Altimeter provided in the Garmin G1000 PDF dis-
plays barometric altitude values in feet on a rolling num-
ber gauge. The Altimeter displays the following infor-
mation:
•
Altitude values
•
Altitude reference bug
•
Altitude trend vector
•
Altitude reference box
•
Barometric setting box
•
Altitude alerter
•
Metric display
The altitude calculated by G1000 GPS receivers is
geometric height above Mean Sea Level and could
vary significantly from the altitude displayed by pres-
sure altimeters.
Refer to Garmin G1000 Maintenance Manual for ser-
vice and troubleshooting information.
34--13--01 -- ALTIMETER TROUBLESHOOTING (TRADITIONAL)
TROUBLE PROBABLE CAUSE REMEDY
Excess scale error. Improper calibration adjustment. Replace instrument.
Excessive pointer oscillation. Defective mechanism. Replace instrument.
High reading. Static pressure system leak. Eliminate leak in static pressure
system.
Setting knob is hard to turn. Wrong lubricant or lack of lubrica-
tion.
Replace instrument.
Inner reference marker fails to move
when setting knob is rotated.
Marker out of engagement. Replace instrument.
Setting knob set--screw is loose or
missing.
Excessive vibration. Tighten instrument screw, if loose.
Replace instrument, if screw is
missing.
Cracked or loose cover glass. Excessive vibration. Replace instrument.
Dull or discolored luminous mark-
ings.
Age. Replace instrument.
34--12--01