Page 4-9
Rev. 1 Jun/11
TESTING AND TROUBLESHOOTING
61-00-75
Propeller Owner's Manual
175
(b) HC-8( )( )( )-1( )( ), -2( )( ), and -3( )( ) propeller
models:
1
Governor is not increasing oil volume in the
propeller.
2
Engine oil transfer bearing is leaking
excessively.
3
Excessive friction in the blade bearings or the
pitch change mechanism
F
. Loss of Propeller Control - HC-82(X,V)(F,L )-6( )( )( )
propeller models:
(1) Propeller goes to uncommanded low pitch (high RPM)
(a) Loss of oil pressure - check:
1
Governor pressure relief valve for proper
operation.
2
Governor pilot valve sticking.
3
Governor drive for damage.
4
Adequate engine oil supply.
5
Engine oil transfer bearing for excessive
leakage.
(2) Propeller goes to uncommanded high pitch (low RPM)
(a) Governor pilot valve sticking.
(3) RPM increases with power and airspeed, propeller RPM
control has little or no effect.
(a) Excessive friction in blade bearings or pitch change
mechanism.
(b) Misalignment between the guide collar and piston
rods.
(c) Engine oil transfer bearing is leaking excessively.
(d) Governor is not increasing oil volume in the
propeller.
OBSOLETE PROPELLER MODELS. SEE COVER PAGE
WARNINGS AND SERVICE BULLETIN HC-SB-61-331
