Maintenance; Sharpening The Saw Chain - stayer OLMO G1-250 Operating Instructions Manual

Grasp the tubular handle (13) firmly with one hand and hold
the rear handle (1) with the other.
With the motor running at moderate speed, push the hand
guard (4) with the rear portion of your hand until actuating
the saw chain brake (4). The saw chain (5) must stop
immediately.
Immediately release the accelerator and release the saw
chain brake.
IMPORTANT: If the saw chain does not stop
immediately in this test, do not proceed with the work
under any circumstances. Contact a STAYER Service
Center.
ALERT: Do not remain a long time checking the brake (4)
risk of burning the friction system.
Adjusting the engine speed
The motor is perfectly adjusted ex works. As time goes by, it
might need small adjustments.
The engine speed increases upon rotating the adjusting
screw to the right.
Rotating to the left, the engine speed is reduced.
Mixture richness adjusting screw "H" (27) at high speed
Mixture richness adjusting screw "L" (28) at low speed
Idling adjusting screw "T" (29)
Adjusting the carburetor (Fig. 46, 47)
- The equipment is adjusted ex works. Only proceed to
adjusting after having discarded other possible causes
such as dirty filters, exhaust pipe full of carbon deposits,
spark plug in bad condition or low-quality gasoline or
excessive or scarce mixture with oil.
- Before adjusting, fill half of the tank and let the machine
warm up keeping it running without load for 5 minutes.
Adjusting low engine speed:
WARNING: It is recommended to adjust the machine at a
technical service.
Adjust the revolutions at idling speed by means of screw T
(29).
Adjust the richness at idling speed acting on L until a
relieved speed is achieved without reaching the highest
speed limit for the previously adjusted position T.
Readjust position T if by acting on L if revolutions rise too
much. The final result will be a sound that must be clean but
not shrill but with a small roaring. Once adjusted, the
machine will start easily and will not get stalled when it is
accelerated.
Release the brake and check that the chain does not rotate
at idling speed. Never allow the saw to rotate at idling
speed. The consequence is a severe risk of accident and of
burning the mechanical brake group with fire hazard. If you
note that the saw rotates at idling speed, reduce the
revolutions until it does not move anymore and repeat the
adjusting process.
Adjusting high engine speed:
Only proceed to this after having adjusted the machine at
low revolutions. When pressing the accelerator to the
maximum, act on screw H (27) until achieving high
revolutions but without ever reaching the maximum. Once
you hear the highest revolutions (clean and sharp scarce
gasoline mixture sound), adjust to reduce the revolutions
only a little until starting to hear a stronger and more low-
ENGLISH
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pitched sound similar to roaring. Revise the low engine
speed adjustment to check that it has not changed due to
the high engine speed adjustment. The result is that the
machine revolutions will rise smoothly and quickly, that it
does not stall at idling speed and with much power and a
minimum smoke emission.
Once adjustment of the low and high engine speed has
been made, the machine is adjusted and ready to work at
maximum power, maximum lifetime of the engine and
smallest consumption.
Warning:
Carbureting a very rich mixture will make the machine
malfunction, heating up excessively, with low power and
expelling much white smoke, filling ducts with carbon
deposits and generating beads (short circuit) at the spark
plug. Moreover, the sound will be that corresponding to low
revolutions, is ugly and irregular.
Carbureting a scarce mixture will cause the machine to
deliver very little power, to lubricate little and with rising
revolutions. In these conditions, there is a severe risk of
breakdowns due to breakage of the piston and of the
crankshaft bearing.
The sound is very accelerated, very shrill and dry.

6. Maintenance

6.1 Sharpening the saw chain (Figs. 48 to 52)
Before carrying out any work at the guide bar
or saw chain, always switch off the engine and
extract the spark plug cap (refer to "Replacing
the spark plug"). Always wear protective
gloves.
The saw chain must be sharpened when:
Sawdust produced when sawing moist wood seems to be
wood meal.
The saw chain enters wood only under great pressure.
The saw is pushed towards the left or towards the right due
to irregular sharpness of the saw chain.
Important: Sharpen frequently but without removing
too much material.
Generally, 2 or 3 passes will be sufficient.
Ask a Service Center for resharpening when you have
already sharpened several times.
Correct sharpening (Fig. 48)
Only use saw chains and guide bars designed
for this chain saw
All blades must have the same length (dimension a).
Blades having different lengths will cause rough operation
of the chain and may produce cracks in the saw chain.
The minimum length of the blade is 3 mm. Do not resharpen
the saw chain when this minimum length has been reached;
at that time the saw chain must be replaced.
The cutting depth is determined by means of the difference
in height between the depth gauge (rounded back) and the
cutting edge.
The best results will be achieved with a depth of the depth
gauge of 0.65 mm.
Excessive depth will increase the recoiling
hazard.
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