O.S. Engines 12XZ Speed Spec II - Manual (Page 11)

20
Turn the engine with starter box to draw fuel
into the engine.
Fuel
Deliver fuel into the carburetor.
Fuel tank side
Now connect glowplug battery lead to heat
the plug filament and start the engine.
Switch on the transmitter and make sure
that each linkage moves correctly.
approx 1mm
Set the throttle opening a little wider that the
factory setting by adjusting the Throttle Stop
Screw.
When the engines does not start or stops
right after started, try the followings.
When the engine starts, warm it up by
repeatedly increasing the rpm to medium
speed and back again to a fast idle with the
mixture set very rich, the glowplug
connected, and the driving wheels clear of
the ground. The rich mixture will provide
adequate lubrrication and cooling indicated
by profuse exhaust smoke.
Set the needle-valve approx. 2 turns open
from the fully closed position. Do not force
the needlevalve to turn beyond a lightly
closed position.
21
It is vitally important to set
the throttle at the correct
position before starting the
engine. If the engine is
allowed to run with the throttle
too far open under ''no load'' conditions (i.e.
with the driving wheels not in contact with the
ground) it will rapidly over-heat and may be
seriously damaged.
Attention:
Next, disconnect the glowplug battery and try
running the car on the track.
If the engine stalls, open the throttle
fractionally, but try to keep the engine running
as rich as possible: if it stops because of
being excessively over-rich, close the Needle-
Valve 15˚ and try again.
throttle trigger
Run the car on the track until one tank of fuel
has been consumed, then close the Needle-
Valve 15˚ and run the car for 3 to 5 full tanks
of fuel.
Repeat this procedure until approx. 2 liters of
fuel have been consumed, during which time
the throttle may be opened for brief bursts of
increased power.
If the engine stops at medium speeds, close
the Mixture Screw 45˚.