TM 55-1510-220-MTF
c.
Defective components.
F6.
One autofeather arm light illuminates when power setting is less than 90 percent N1
(AUTOFEATHER switch in ARM position).
a.
Defective or out of adjustment power switch.
F7.
Neither autofeather arm light illuminates when power levers are advanced (AUTOFEATHER
switch in ARM position).
a.
Defective autofeather switch.
F8.
One arm light does not illuminate when power levers are advanced (AUTOFEATHER switch in
ARM position).
a.
Defective or out of adjustment power switch.
b.
Defective No. 1 (12 PSI) torque pressure switch.
F9.
Both arm lights remain illuminated when one power lever is retarded (AUTOFEATHER switch in
ARM position).
a.
Defective or out of adjustment power switch.
b.
Defective torque pressure switch.
F10.
Propeller does not start to feather after engine torque falls below 9-14 percent (AUTOFEATHER
switch in ARM position).
a.
Defective No. 2 (6.5 PSI) torque pressure switch on retarded engine.
b.
Defective autofeather dump valve.
F11.
One arm light does not illuminate when power levers are advanced to 90 percent N1
(AUTOFEATHER ARM-TEST switch in TEST position).
a.
Defective No. 1 (12 PSI) torque pressure switch.
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