Tensioning The Chain; Checking Chain Tension - Stihl MS 391 Safety Manual

1
3
1
2 4
N
Fit the guide bar over the studs (1) –
the cutting edges on the top of the
bar must point to the right.
N
Engage the peg of the tensioner
slide in the locating hole (2) –- place
the chain over sprocket (3) at the
same time.
N
Turn the tensioning
screw (4)clockwise until there is
very little chain sag on the
underside of the bar – and the drive
link tangs are engaged in the bar
groove.
N
Refit the sprocket cover and screw
on the nuts only fingertight.
N
Go to chapter on "Tensioning the
Saw Chain"
MS 311, MS 391

Tensioning the Chain

1
Retensioning during cutting work:
N
Shut off the engine.
N
Loosen the nuts.
N
Hold the bar nose up.
N
Use a screwdriver to turn the
tensioning screw (1) clockwise until
the chain fits snugly against the
underside of the bar.
N
While still holding the bar nose up,
tighten down the nuts firmly.
N
Go to "Checking Chain Tension".
A new chain has to be retensioned more
often than one that has been in use for
some time.
N
Check chain tension frequently –
see chapter on "Operating
Instructions".

Checking Chain Tension

N
Shut off the engine.
N
Wear work gloves to protect your
hands.
N
The chain must fit snugly against
the underside of the bar and it must
still be possible to pull the chain
along the bar by hand.
N
If necessary, retension the chain.
A new chain has to be retensioned more
often than one that has been in use for
some time.
N
Check chain tension frequently –
see chapter on "Operating
Instructions".
English
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