O.S. Engines 21RG-X - Manual (Page 8)

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CARBURETOR CONTROLS
The Needle-Valve:
The Mixture Control Screw:
The Throttle Stop Screw:
For setting the minimum idling speed:
Three adjustable controls are provided on this
carburetor.
For adjusting the mixture strength when the throttle
is fully open.
For adjusting the mixture strength at part-throttle
and idling speeds, to obtain steady idling and
smooth acceleration to mid speeds.
Needle Valve
Mixture Control Valve
Assembly Screw
Throttle Stop Screw
Ball Link
Slide Valve
Guide Screw
NOTE: Readjustment may be necessary,
occasionally to allow for changes in fuel formula,
gear ratio or clutch engagement point.
The somewhat violent changes of vehicle attitude
that occur in off-road running, combined with the
fact that, in buggy type cars, the fuel tank is often
located some way from the carburetor, means that
fuel 'head' at the carburetor can vary a and upset
running.Therefore,it is recommended that a muffler
pressurized fuel feed system be used.
Never run your vehicle without installing the air
cleaner. Dust and dirt that may otherwise be drawn
into the engine will rapidly shorten its life.
PRESSURIZED FUEL SYSTEM
•
•
Silencer
Fuel Tank
Silicone fuel line
Connect suitable length of
Silicone fuel line between fuel
tank and silencer.
14
and contains between 10% and 30% nitromethane. As
a starting point, we recommend a fuel containing 10%
nitromethane, changing to a fuel containing more nitro
if necessary. When the brand of fuel is changed, or the
nitro content increased, it is advisable to repeat the
running-in procedure referred to in the RUNNING-IN
paragraphs. For consistent performance and long
engine life, it is essential to use a good quality fuel
containing NOT LESS THAN 18% lubricant. Please
note that with high-nitro fuels, although power may be
increased for competition purposes, glowplug elements
do not last so long and engine life will be shortened.
Model engine fuel is poisonous. Do not
allow it to come into contact with the eyes or
mouth. Always store it in a clearly marked
container and out of the reach of children.
Model engine fuel is also highly flammable.
Keep it away from open flame, excessive heat,
sources of sparks, or anything else which
might ignite it.
Reminder!
GLOWPLUG BATTERY
The power source for heating the glowplug may be either
a large heavy-duty 1.5Volt dry cell, or a 2-Volt rechargeable
BATTERY LEADS
These are used to conduct current from the battery to
the glowplug. For convenience,special leads with a
suitable clip to fit the glowplug terminal, are
commercially available.
LONG SOCKET WRENCH
Recommended for easy removal and
replacement of the angled and recessed
glowplug, the O.S.Long Socket Wrench
incorporates a special grip.
SILICONE FUEL LINE
Heatproof silicone fuel line of approx. 5mm
o.d. and 2mm bore is required for the piping
between the fuel tank and engine.
FUEL BOTTLE OR PUMP
For filling the fuel tank, a simple, polyethylene
"squeeze" bottle, with a suitable spout, is required.
ELECTRIC STARTER AND STARTER BATTERY
Use an electric starter with 12-volt
battery for starting the MAX-
21RG/RG(P).
lead-acid cell with extended leads (or a resistance) to
reduce the applied voltage to approximately 1.5 -V.