O.S. Engines FS-26S-CX - Manual (Page 16)

It is vitally important to set
the throttle at the correct
position before attempting
to start the engine. If the
engine is allowed to run
with the throttle too far
open under "no load"
conditions, it will rapidly overheat and may be
seriously damaged.
Remember!
Now, refuel and re-start the engine, opening
the throttle just sufficiently to engage the
centrifugal clutch and allow the car to run on
the track without stalling and still with the
needle-valve set rich to promote cool
running. ●
After running the engine for four or five tanks
of fuel, begin closing the needle a few degrees
(1 to 3 cllicks) between succeeding runs. Also,
vary its speed, from idling to medium RPM,
with the throttle. See sketch. ●
Eventually, the engine will begin to loosen up
sufficiently to allow short bursts of full-throttle
acceleration with the needle-valve at its
optimum setting. ●
Do not close the needle-valve any further. If
you do so, the engine will begin to overheat
and the car will slow down, accompanied by
visibly diminished exhaust smoke. In this
event, bring the vehicle to a halt immediately
and reopen the needle-valve 20
°
to 30
°
.
Note!
Now open the needle-valve 20
°
-30
°
from the
setting at which the highest straight line
speed is obtained. This slightly rich setting
should provide the optimum balance. Run
the car for about three more tanks of fuel to
allow fine-tuning of any final adjustments.
●
Four stroke engine have stronger
compression than two stroke engines.
Hold the chassis firmly when pulling the
recoil starter. Also, wearing of gloves is
recommended to avoid any risk of injury.
Note!
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