O.S. Engines FS-26S-C II - Manual (Page 6)

10
The FS-26S-C Ver. is supplied with an O.S. Type F
glowplug, specially designed for O.S. four-stroke
engines.
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.
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.
However, plug life can be extended and engine
performance maintained by careful use, i.e.:
Apart from when actually burned out, a plug may
need to be replaced because it no longer delivers its
best performance, such as when:
When to replace the glowplug
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.
Glowplug life
Particularly in the case of very high performance
engines, glowplugs must be regarded as expendable
GLOWPLUG
11
AIR CLEANER TYPE 102S
INSTALLATION OF
AIR CLEANER
Carefully clean the carburetor,
removing any old adhesive or
sealant that may have been
previously used on the outside
of the air intake.
Press the air cleaner body firmly
over the carburetor air intake. Make sure that the
outer rim of the air intake engages the internal
annular groove in the air cleaner: failure to do so
may result in the air cleaner falling off.
It has a single filter element and is intended primarily
for circuit racing, where conditions are less damaging
than the very dusty, loose surfaces of off-road operation
for which the double-element Type 101 and 102 Air
Cleaners are recommended.
The lower height of the Super Air-Cleaner 102S also
facilitates easier installation in cars where available
space may be restricted.
Position the air cleaner correctly, so that it does not interfere
with the cylinder-head or obstruct the needle-valve.
INSTALLING THE FILTER ELEMENT
The element is already impregnated with a special
filter oil. As this oil is very sticky, take care, when
handling it, to prevent dust or dirt from adhering to the
element. If your fingers become contaminated, wash
them with soap and water.
During storage, the oil may
have become unevenly
dispersed through the element.
This will be indicated if the blue
colour of the element material
appears patchy. In this case,
place the element in a small
plastic bag and gently rub it
between finger and thumb to
redistribute the oil.
It is advisable to replace the filter element with a new
one after not more than one hour of running time.
Always remove contaminated elements carefully, to
ensure that dirt cannot enter the carburetor.
REPLACEMENT OF ELEMENT
Insert beneath flange