Cessna T188C - Description; Trouble Shooting; Turn Coordinator

MODEL
188 &
T188
SERIES
SERVICE
MANUAL
15-43. TROUBLE SHOOTING (Cont).
TROUBLE PROBABLE CAUSE REMEDY
HAND
SLUGGISH IN RE-
Defective mechanism.
Replace
instrument.
TURNING
TO ZERO.
Low voltage.
Correct
voltage.
POINTER DOES
NOT Defective
mechanism.
Replace instrument.
INDICATE
PROPER
TURN.
HAND DOES NOT SIT ON
Gimbal and rotor
out of Replace
instrument.
ZERO.
balance.
Hand incorrectly sits on rod. Replace instrument.
Sensitivity spring adjustment Replace instrument.
pulls hand off zero.
IN COLD TEMPERATURES. Oil in indicator becomes Replace instrument.
HAND FAILS TO RESPOND too thick.
OR IS SLUGGISH.
Insufficient bearing end play. Replace instrument.
Low voltage. Correct voltage.
NOISY GYRO.
High voltage.
Correct voltage.
Loose or defective
rotor
Replace
instrument.
bearings.
15-44. TURN
COORDINATOR.
motion roll
and yaw axes which is projected
on a
single indicator. The gyro is a non-tumbling type re-
15-45. DESCRIPTION.
The turn coordinator
is an quiring no
caging mechanism and incorporates
an
electrically
operated, gyroscopic,
roll-rate turn a. c.
brushless spin motor with a solid
state inver-
indicator. Its gyro
simultaneously
senses rate of
ter.
15-46.
TROUBLE
SHOOTING.
TROUBLE
PROBABLE
CAUSE
REMEDY
INDICATOR
DOES NOT
Friction
caused
by contamination
Replace
instrument.
RETURN
TO CENTER.
in
the indicator
damping.
Friction
in gimbal assembly.
Replace
instrument.
DOES
NOT
INDICATE
A
Low
voltage.
Measure
voltage
at
instrument.
STANDARD
RATE
TURN
Correct
voltage.
(TOO
SLOW).
Inverter
frequency
changed.
Replace
instrument.
NOISY
MOTOR.
Faulty bearings.
Replace
instrument.
15-13