Alpina B 28J Gebrauchsanweisung Seite 18

6
EN
CHAIN SPROCKET
Regularly check the condition of the sprocket with
your local retailer and replace it when it is worn.
Do not mount a new chain with a worn sprocket or
vice-versa.
SHARPENING THE CHAIN (Fig. 12)
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:
– Disassemble the pruner from the brush cutter
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).
Chain pitch
inches: 3/8 Mini
mm: 9,32
To ensure that the chain-
If the chain is not suffi-
Limiter tooth level (a)
– 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.
BAR MAINTENANCE (Fig. 13)
To avoid asymmetrical wear on the bar, make sure
it is turned over periodically.
To keep the bar in perfect working order, proceed
as follows:
– grease the bearings on the nose sprocket (if
present) with the syringe;
– Clean the bar groove with the scraper (not in-
cluded);
– clean the lubrication holes;
– with a flat file, remove burr from the edges and
level off the guides.
Replace the bar whenever:
– the groove is not as deep as the height of the
drive links (which must never touch the bottom);
– the inside of the guide is worn enough to make
the chain lean to one side.
BAR AND CHAIN COMBINATIONS
Accessories with the following code must be used
on this machine:
118801755/0 = bar (Length 25 cm / 10"
118801756/0 = chain (Pitch 3/8" mini).
Given product evolution, the above mentioned
tools may be replaced in time with others having
similar interchangeable and operating safety char-
acteristics.
a = 0,45 mm (0,018")
MAINTENANCE AND STORAGE
Groove width 1,27 mm / 1/20")
File diameter (d)
d = 4 mm (5/32")