Glow Plug - O.S. engine MAX FXi 46 Owner's Instruction Manual

tank is 5-10mm (1/4-3/8") above the level of
the needle valve.
Be sure to use a pressurized fuel system by
connecting the muffler pressure nipple to
the vent pipe of the fuel tank.

GLOW PLUG

Since the glow plug and fuel combination used
may have a marked effect on performance and
reliability, it would be worthwhile to experiment
with different plug types.
Recommended O.S. plugs are Nos. 8, A5
and A3. Carefully install plug finger-tight,
before final tightening with the correct size
plug wrench.
The Role of the Glow Plug
With a glow plug 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 becomes cooler and
ignition is retarded.
Glow Plug Life
Particularly in the case of very high
performance engines, glow plugs must be
regarded as expendable. However, plug life
can be extended and engine performance
maintained by careful use, i.e.:
• Install a plug suitable for the engine.
• Use fuel containing a moderate
percentage of nitro methane unless
more is essential for racing events.
• Do not run the engine too lean and do
not leave the battery connected while
adjusting the needle.
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