Stiga SP 52 Operator's Manual page 39

MAINTENANCE AND STORAGE
housing (6) being careful it does not penetrate in
the suction duct (7).
– Reassemble the filter element (5) only when
thoroughly dry, being careful to perfectly line up
the two side protrusions (8) with the filter hous-
ing protrusions.
– Reassemble the two side stops (4).
– Reassemble the cover (2) and hook the three
springs (1).
CHECKING THE SPARK PLUG (Fig. 24)
The spark plug can be accessed by removing the
air filter cover.
Periodically remove and clean the spark plug using
a metal brush to get rid of any deposits.
Check and reset the correct distance between the
electrodes.
Replace the spark plug and fasten it firmly using the
supplied wrench.
The spark plug must be replaced with one with the
same characteristics whenever the electrodes
have burnt or the insulation has worn, and in any
case every 100 working hours.
TUNING THE CARBURETTOR
The carburettor is tuned by the manufacturer to
achieve maximum performance in all situations,
with a minimum emission of toxic gas in compli-
ance with the regulations in force.
When performance is poor, first check that the
chain runs smoothly and the bar rails are not dis-
torted, then contact your dealer to check the car-
buretion and the engine.
• Tuning minimum speed
WARNING!
when the engine is running idle. If the chain
moves when the engine is running idle, con-
tact your dealer to correctly regulate the en-
gine.
The chain must not move
SHARPENING THE CHAIN
WARNING!
saw works safely and efficiently, it is essential
that the cutting components are well-sharp-
ened.
Sharpening is necessary when:
• The sawdust looks like dust.
• Cutting becomes more difficult.
• The cut is not straight.
• Vibrations increase.
• Fuel consumption increases.
WARNING!
ciently sharpened, the kick-back's risk in-
creases.
A specialized centre will sharpen the chain using
the right tools to ensure minimum removal of ma-
terial and even sharpness on all the cutting edges.
If you sharpen the chain yourself, use special
round-section files with the right diameter de-
pending on the type of chain (see "Chain Mainte-
nance Table"). You need a certain amount of skill
and experience to avoid damaging the cutting
edges.
Sharpen the chain as follows (Fig. 25):
– Switch off the engine, release the chain brake
and secure the bar with the chain in a vice so that
the chain can run smoothly.
– Tighten the chain if it is loose.
– Mount the file in the guide and then insert it in the
tooth at a constant angle from the cutting edge.
– Sharpen in a forward motion a few times and re-
peat this on all the cutting edges facing the same
way (right or left).
– Turn the bar over in the vice and repeat on all the
other cutting edges.
– Check that the limiter tooth does not stick out fur-
ther than the inspection instrument and file any
projecting parts with a flat file, rounding off the
edge.
– After sharpening, remove all traces of filing and
dust and lubricate the chain in an oil bath.
Replace the chain whenever:
– The length of the cutting edges reduces to 5
mm or less;
– There is too much play between the links and the
rivets.
EN
To ensure that the chain-
If the chain is not suffi-
15