Operation Manual

39MS 650, MS 660
English / USA
1 = Take out the air baffle vertically
2 = Pull off the spark plug boot
: Unscrew and dry off the spark plug -
: Set the Master Control lever to
“Stop” position d
: Press down the interlock lever, open
the throttle wide and, at the same
time, crank the engine several times
with the starter to clear the
combustion chamber.
: Refit the spark plug and connect the
spark plug boot –
reassemble the other parts.
: Set Master Control lever to “Warm
Start” n – even if engine is cold.
: Press in decompression valve
again.
: Now start the engine.
During 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
unnecessary high loads during the
break-in period. As all moving parts
have to bed in during the break-in
period, the frictional resistances in the
engine are greater during this period.
The engine develops its maximum
power after about 5 to 15 tank fillings.
Do not make the mixture leaner to
achieve an apparent increase in
power – this could damage the
engine – see “Adjusting
Carburetor”.
Always disengage the chain brake
before opening the throttle. Running
the engine at higher revs with the
chain brake engaged (saw chain at
a standstill) will quickly damage the
engine and chain drive (clutch,
chain brake).
During operation
Check chain tension frequently
A new chain has to be retensioned more
often than one that has been in use for
some time.
Chain cold:
Tension is correct when chain fits snugly
against the underside of the bar and can
still be pulled along the bar by hand.
Retension if necessary – see
“Tensioning the Saw Chain”.
Chain at operating temperature:
The chain stretches and begins to sag.
The drive links must not come out of the
bar groove – the chain may otherwise
jump off the bar.
Retension the chain – see “Tensioning
the Saw Chain”!
Always slacken off the chain after
finishing work. The chain contracts
as it cools down. If it is not
slackened off, it can damage the
crankshaft and bearings.
1
2
137BA009 KN
Operating Instructions