Fuel Tank Location; Glowplug - O.S. engine MAX-46AXII Instruction Manual

FUEL TANK LOCATION

Suggested fuel tank capacity is approx 300cc.
This will allow 12-13 minute flights.
Locate the fuel tank so that the top of the tank is 5-
10mm (1/4-3/8") above the level of the needle-valve.
Attention to tank height
JAPAN

GLOWPLUG

Since the glowplug 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 No.6
(Former A3) , No.7 and No.8.
Carefully install plug finger-tight, before
final tightening with the correct size plug
wrench.
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.
Be sure to use a pressurized fuel system by
•
connecting the muffler pressure nipple to the vent-
pipe of the fuel tank.
Plug (commercially available)
12
Glowplug life
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.:
Install a plug suitable for the engine.
Use fuel containing a moderate percentage of
nitromethane 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.
When to replace the glowplug
Apart from when actually burned out, a plug may
need to be replaced because it no longer delivers its
best performance, such as when:
Filament surface has roughened and turned white.
Filament coil has become distorted.
Foreign matter has adhered to filament or plug
body has corroded.
Engine tends to cut out when idling.
Starting qualities deteriorate.
13
Fuel level
10-15mm