O.S. Engines 91SZ-H - Manual (Page 11)

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STARTING
Open
Be sure to use a muffler pressurized fuel feed. Use
the same fuel as you intend to employ for actual
operation of your model.
1.
2.
Opening and closing of the Needle-Valve
Turn the needle clockwise to
close the needle-valve, and turn
the needle counter-clockwise to
open the needle-valve as shown
in the sketch.
High Speed needle-valve:
exactly two turns open from the fully closed
position.(Note: If a different muffler is used, this
setting may require readjustment)
Idle Mixture Control Screw:
at basic position when the engine leaves the
factory.
exactly two turn open from the fully closed position.
Medium Speed needle-valve:
Close
4.
5.
Checking the rotating direction of the starter
Make sure that the starter rotates
to the direction shown in the
sketch. If the direction is reverse,
reverse the leads on battery.
Inserting the starter shaft
Insert the starting shaft into the
shaft cup securely.
3. Preparation of the starter
Install the starting shaft to the
starter securely.
Improper installation will allow the
shaft to swing creating a
dangerous situation.
21
6. Priming
Without energizing the glowplug, open the throttle
a little from the idling position. Turn the engine
over using the starter until the fuel is seen to reach
carburetor.
In case the engine does not stop.
Hold the rotor head, and pinch the fuel line to stop the
fuel supply. If it still does not stop, pull off the fuel line
from the carburetor.
It is necessary to readjust the throttle linkage so that
the carburetor rotor is fully closed when the throttle
stick and throttle trim on the transmitter are fully
pulled Down.
Stopping the engine
Fully pull down the throttle trim on the transmitter.
Starting
Connect the battery to the glowplug and start the
engine by applying the starter. When started, switch
off the starter and withdraw the starting shaft after
making sure the rotation of the starter shaft stops.
Preparation of starting
Make sure that the transmitter
throttle stick is at the fully closed
position and the throttle trim at center
position, and make sure that idle-up
switch on the transmitter is off. Hold
the rotor head by hand so that rotor
cannot rotate when the engine is Started. Also, steady
the model with a foot on the landing gear skid.
7.
8.
9.
NOTE:
If the throttle response is poor or the engine
stops due to a temporarily over-rich mixture im-
mediately after the engine is started, pinch the
fuel line for one or two seconds until the engine
r.p.m. increase and the engine runs steadily.
Reminder!
Never touch, or allow any object to
come into contact with, the rotating
rotor.