O.S. engine GT33 - Running-In; Starting

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Always check the throttle linkage.
is disconnected, the engine becomes
If it
AN uncontrollable, which may result in a serious
accident.
Take care that loose clothing (ties, shirt sleeves,
scarves, etc.) do not come into contact with the
propeller. Do not carry loose objects (such as
pencils, screwdrivers, etc.) in a shirt pocket from
where they could fall through the propeller arc.
Use an electric starter for this engine.
The wearing of safety glasses is also strongly
recommended.
If you try hand starting, be sure to use a chicken
stick or heavy glove. Never attempt to start the
engine with bare hand.
Be sure to carry out adjustments of the high
speed needle and slow speed needle after
stopping the engine.
RUNNING-IN / STARTING
@ Use a fuel with increased oil content and set the needle a
little on the rich side. Too rich a needle setting may cause
misfiring or erratic running due to fouling of the plug.
@ Use a 25:1 fuel/oil mixture if the particular brand of oil
states 50:1 mix. Set only the high speed needle 100-200
below maximum rpm. The low speed needle need not be
richened.
@ No need to carry out running-in on a bench nor with the
model fixed. Just fly the model with the above mentioned
fuel and needle setting.
@ A total of 10 flights (3-4 litters fuel) are required.
Avoid prolonged full throttle running at initial stage, and
gradually extend the full throttle running time.
WARNING:
When ground running the engine, avoid dusty or sandy
locations. If dust or grit is drawn into the engine, this can
have a ruinous effect, drastically shortening engine life in
Do not start your engine in an area containing
loose gravel or sand. The propeller may throw
such material in your face and eyes and cause
injury.
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18
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a matter of minutes.
Ill Initial needle position
When starting the engine for the first time, set both the
high speed needle and the slow speed needle two turns
open from the fully closed position.
With this position both high and slow speed mixtures will
be rich. If the settings are upset, come back to this setting
and adjust them according to procedure in the needle
setting section.
II Starting by an electric starter
1. Turn on the transmitter switch.
2. Turn on the receiver switch.
3. Turn on the ignition switch.
4. Open the choke valve fully.
5. Pull down the throttle stick on the transmitter fully or to the
1/8 opened position ( 2 to 3 clicks). (With the throttle stick
half to fully advanced, the fuel will not be delivered to the
carburetor suitably when an electric starter is applied.
Also, the model will move forward with engine high power
right after it is started, which is very dangerous.)
6. Tell the helper and onlookers that you will start the engine
now and have the
helper hold the model securely.
7. Apply the electric starter.
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ll Starting with a Chicken stick or gloved hand
(It is suggested to use an electric starter for safety.)
1. Turn on the transmitter switch.
. Turn on the receiver switch.
. Turn on the ignition switch.
+f U Nm
. Open the choke valve fully.
5. Pull down the throttle stick on the transmitter fully or to the
1/8 opened position ( 2 to 3 clicks).
6. Flip the propeller until the fuel reach the carburetor and
you hear explosion several times.
7. Open the choke valve fully.
8. Tell the helper and onlookers that you will start the engine
now and have the helper hold the model securely.
9. Flip the propeller with a Chicken stick to start the engine.
(Usually the engine starts with 2 to 3 flips.)
Note
If you have only short runs or the engine does not start
with more than 5 flips, most probably priming is not
sufficient. Remove the plug to check if it is wet.
If it is wet, replace it or wait until it becomes dry.
Then, flip the propeller quickly 10 times without installing
the plug to eject the fuel in the engine.
Then, install the plug and repeat the procedure.