O.S. Engines 46FX-H Ring - Manual (Page 21)

INSTALLATION OF THROTTLE SERVO
After fitting the engine in the helicopter, please observe the following recommendations when linking the throttle
servo to the carburetor.
Locate the servo so that its output
arm and the throttle pushrod are, as
closely as possible, directry in line
with carburettor's throttle arm, as
shown.
Note : If differential throttle movement
is required, make necessary adjust-
ment at the servo output arm, not at
the throttle lever.
INCORRECT-One-way throttle lever movement
should not be more than 45
°
When the throttle is fully open or fully closed, the throttle lever
angle should not be more than 45˚ either side of the mid-point
of its travel (and where it is at a 90˚ angle to hte pushrod),
otherwise throttle rotor movement may become inhibited or may
even lock up. Also, some lubricants may affect the throttle rotor
movement.
Please note that the throttle lever angles of the O.S. Type 40C
carburettor are well within these limits-requiring only 75˚ from
the fully open to fully closed positions.
CORRECT-Throttle lever
movement should be dis-
posed symmetrically,as
shown.
90˚
Fully open
position
Fully closed
position 90˚ A
B
Use outer hole.
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