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15.11 Shut off the engine
1
201
1BA023 KN
► Move Master Control lever (1) to Stop 0.
15.12 If Engine Does Not Start
If you did not move the Master Control lever from
the choke closed position
l
to the choke open
position
j
quickly enough after the engine
began to fire, the engine is probably flooded.
► Move Master Control lever to Stop 0.
► Remove the spark plug – see "Spark Plug".
► Dry the spark plug
► Crank the engine several times with the starter
to clear the combustion chamber.
► Refit the spark plug – see "Spark Plug".
► Set the master control lever to starting accel‐
eration
n
– even if the engine is cold
► Restart the engine
15.13 If Fuel Tank Has Been Run
Completely Dry and Then
Refueled
► Press the bellows of the manual fuel pump at
least 9x
► Set the Master Control lever to the starting
throttle position
n
► Move the choke lever to the closed position
l
► Continue cranking 2x
► Move the choke lever to the open posi‐
tion
j
.
► Restart the engine
16 Operating Instructions
16.1
During the break-in period
A factory new machine should not be run at high
revs (full throttle off load) for the first three tank
fillings. This avoids unnecessarily high loads dur‐
ing the break-in period. As all moving parts have
to bed in during the break-in period, the frictional
resistances in the shortblock are greater during
this period. The engine develops its maximum
power after about 5 to 15 tank fillings.
16.2
During work
NOTICE
Do not make the mixture leaner to achieve an
apparent increase in power – this could damage
the engine – see "Adjusting the Carburetor".
NOTICE
Open the throttle only when the chain brake is
off. Running the engine at high revs with the
chain brake engaged (chain locked) will quickly
damage the shortblock and chain drive (clutch,
chain brake).
16.2.1
Check chain tension frequently
A new saw chain must be retensioned more fre‐
quently than one that has been in use already for
an extended period.
16.2.2
Chain cold
Tension is correct when the chain fits snugly
against the underside of the bar but can still be
pulled along the bar by hand. Retension if neces‐
sary – see "Tensioning the Saw Chain".
16.2.3
Chain at operating temperature
The chain stretches and begins to sag. The drive
links must not come out of the bar groove on the
underside of the bar – the chain may otherwise
jump off the bar. Retension the chain – see "Ten‐
sioning the Saw Chain".
NOTICE
The chain contracts as it cools down. If it is not
slackened off, it can damage the crankshaft and
bearings.
16.2.4
After a long period of full-throttle oper‐
ation
After a long period of full-throttle operation, allow
engine to run for a while at idle speed so that the
heat in the engine can be dissipated by flow of
cooling air. This protects engine-mounted com‐
ponents (ignition, carburetor) from thermal over‐
load.
16.3
After finishing work
► Slacken off the chain if you have retensioned it
at operating temperature during work.
16 Operating Instructions
English
0458-506-0121-C
25