O.S. Engines 55HZ-H Hyper - Manual (Page 11)

20
BASIC POSITION OF MIXTURE CONTROL SCREW
(Mixture Control Valve)
Rich
Mixture Control Valve
MIxture Control Screw
Lean
As delivered, the Mixture Control Screw is
positioned at approximately the center as shown in
the sketch. Mixture gets lean when the Mixture
Control Screw is turned right, while mixture gets
rich when the Mixture Control Screw is turned left.
With a model helicopter, adjustments vary with
combined various factors such as climatic
conditions, fuel, muffler, main rotor, weight of the
model, gear ratio, etc. Therefore the Mixture
Control Screw position varies with each model and
set- up, and it is normal if the Mixture Control Screw
position is off the center.
89 degrees
When the triangle mark on the carburetor rotor meets
the far right mark, the throttle is fully closed. When
the triangle mark meets the top mark, the throttle is
fully open. The range is 89 degrees. You may use
the other three marks as the reference marking of
throttle opening to your preference when hovering.
WARNING!
Never try to check the triangle mark position
while the engine is running and rotor is rotating,
or you may be hit by rotating rotor which results
in serious injury. Stop the engine and rotor
before checking the triangle mark position.
Carburetor Rotor Carburetor Body
Fully closed
position
Fully opened position
As shown in the sketch, the carburetor has
graduation marks.
GRADUATIONS ON THE CARBURETOR BODY
21
Be sure to use an electric starter to start
the engine.
Fill the fuel tank with fuel. When filled, prevent the
fuel from flowing into the carburetor with a
commercially available fuel stopper, etc. Release
the stopper before starting the engine. 1.
2.
Starting procedure is as follows:
WARNING
When checking the plug element hold the plug
with tools, such as pliers, etc.
Do not hold near your face or the fuel remaining
in the filament may burn you.
Glow Plug Igniter
Pliers
Element glows when energized.
Replace the plug when the
element does not glow or is
burnt out.
Make sure that plug element glows red, and install
the plug in the cylinder head.
Never fail to check the tightness of screws
and nuts, especially engine mounting and
moving parts (e.g. throttle lever).
Be sure to use a muffler pressurized fuel feed.
Use the same fuel as you intend to employ for
actual operation of your model.
STARTING