TM 1-1510-225-MTF
b. Defective No. 1 (4.7 PSI) torque pressure switch.
F9.
Both arm lights remain illuminated when one
POWER lever is retarded (AUTOFEATHER
switch in ARM position). Defective or out of
adjustment power lever switch.
F10.
Propeller does not start to feather after engine
torque fails below 7% (AUTOFEATHER switch
in ARM position).
a. Defective No. 2 (3.1 PSI) torque pressure switch
on retarded engine.
b. Defective autofeather dump valve.
F11.
One autofeather arm light does not illuminate
when POWER levers are advanced to 90 percent
N,, (AUTOFEATHER ARM - TEST switch in
TEST position).
a. Defective No. 1 (4.7 PSI) torque pressure switch.
F12.
Both autofeather arm lights extinguish when one
POWER lever is retarded (engine torque 7 to
12% on retarded engine, AUTOFEATHER ARM-
TEST switch in TEST position).
a. Defective No. 2 (3.1 PSI) torque pressure switch
on retarded engine.
F13.
One autofeather arm light remains illuminated
after torque of one engine falls below 7% on
retarded engine, AUTOFEATHER ARM-TEST
switch in TEST position).
a. Defective No. 2 (3.1 PSI) torque pressure switch
on retarded engine.
b. Defective autofeather dump valve.
F14.
Propeller slow to feather.
a. Preformed packing leak at transfer tube or transfer
housing.
b. Defective propeller governor.
F15.
Propeller slow to unfeather.
a. Defective propeller governor.
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