Page 4-13
Rev. 1 Jun/11
TESTING AND TROUBLESHOOTING
61-00-75
Propeller Owner's Manual
175
(j) Airfoil profile identical between blades (after
overhaul or rework for nicks - verify at appropriately
licensed propeller repair facility).
(k) Hub, blade, or blade clamp for damage or cracking.
(l) Grease or oil leakage from a seemingly solid surface
of the hub, blade clamp, or blade.
(m) Blade deformation.
NOTE:
Dynamic balancing is recommended after
installing or performing maintenance on
a propeller. While normally an optional
task, it may be required by the engine or
airframe manufacturer to make certain the
propeller/engine combination is balanced
within close tolerances before operation.
Refer to the engine or airframe manuals,
and the Maintenance Practices chapter of
this manual.
L
. Propeller Overspeed
(1) Check:
(a) Tachometer error.
(b) Low pitch stop adjustment.
(c) Governor maximum RPM set too high.
(d) Loss of oil pressure - HC-82(X,V)(F,L)-6( )( )( )
1
Governor failure
2
Excessive leakage in the governor oil supply to
the propeller.
(e) Broken spring causes momentary overspeed -
HC-8( )( )( )-2( )( ) and -3( )( ) propeller models.
(f) Governor pilot valve jammed, supplying high
pressure only - HC-8( )( )( )-1( )( ), -2( )( ), and
-3( )( ) propeller models.
M
. Propeller Underspeed
(1) Check:
(a) Tachometer error.
(b) Excessive transfer bearing leakage -
HC-8( )( )( )-1( )( ), -2( )( ), and -3( )( ) propeller
models.
OBSOLETE PROPELLER MODELS. SEE COVER PAGE
WARNINGS AND SERVICE BULLETIN HC-SB-61-331
