O.S. Engines 32SX-MX - Manual (Page 9)

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NOTE: Because, in the interests of personal
safety, dismantling of the starter mechanism
isstrongly discouraged, the Recoil Starter is
available for replacement only as a pre-
assembled unit. However, some related parts,
such as Starting Shaft and Rear Adaptor, are
obtainable separately. (See Parts List.)
Try to avoid spilling fuel over the starter unit
and its cord. Some fuels have a detrimental
effect on these parts.
The starter prevents the engine from being
rotated in the wrong direction. The unit will be
damaged if you attempt to force the flywheel
in the opposite direction (i.e. clockwise when
viewed from the crankshaft end).
GLOWPLUG
Since the compatibility of the glowplug and fuel can
have a marked effect on performance and reliability, it
is suggested that the user selects the R/C type plug
found most suitable after practical experiments.
Generally, for a fuel containing about 30%
nitromethane, a medium heat range glowplug will be
suitable.
The role of the glowplug
With a glowplug engine, ignition is initiated by the
application of a 1.5-volt power source. When the
battery is disconnected, the heat retained within the
combustion chamber remains sufficient to keep the
plug filament glowing, thereby continuing to keep the
engine running. Ignition timing is 'automatic': under
reduced load, allowing higher rpm, the plug becomes
hotter and, appropriately, fires the fuel/air charge
earlier; conversely, at reduced rpm, the plug become
cooler and ignition is retarded.
For higher nitro fuel, a cold rated plug may be
required, whereas, for lower nitro fuel, a hot rated
plug may be best. However, the O.S. No.8 glowplug
may be employed irrespective of the nitro content of
the fuel.
Glowplug life
Install a plug suitable for the engine. ¡
¡
Particularly in the case of very high performance
engines, glowplugs must be regarded as expendable
items. However, plug life can be extended and engine
performance maintained by careful use, i.e.:
Use fuel containing a moderate percentage of
nitromethane unless more is essential for racing events.
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