Tensioning The Saw Chain; Lubricating The Saw Chain And Guide Bar - Stihl MSA 120 C Instruction Manual

English
NOTICE
The top and bottom of the guide bar are symmetrical, and
the bar may be mounted with the printing facing up or down.
Flipping the guide bar each time the chain is sharpened or
changed will help reduce uneven wear and improve its
service life.

15.3 Tensioning the Saw Chain

WARNING
To reduce the risk of severe personal injury from chain
derailment, check chain tension frequently, @ 6.5. At
operating temperatures, the chain stretches and sags. New
saw chain tends to stretch more than used chain. Tension
the saw chain so that the drive links cannot come out of the
groove on the underside of the guide bar.
To properly tension the saw chain:
► Switch off the chain saw, @ 18.2.
► Engage the chain brake, @ 16.1.
► Remove the battery, @ 17.2.
► Raise the handle of the wingnut (1).
► Turn the wingnut counterclockwise twice or until the saw
chain is loose.
► Disengage the chain brake, @ 16.2.
2
40
► Turn the adjusting wheel (2) clockwise to tighten the
► If the chain cannot be moved along the guide bar, it is too
► Once the chain is properly tensioned, tighten the wingnut
NOTICE
Always release tension on the chain after finishing work. The
chain contracts as it cools down. If it is not slackened, it can
damage the drive shaft and bearings. Properly re-tension
the chain before using the saw again.

15.4 Lubricating the Saw Chain and Guide Bar

15.4.1 Bar and Chain Lubricant
Never operate your saw without bar and chain lubrication. If
the chain runs dry, the cutting attachment will be damaged
beyond repair within a very short time. A damaged chain
may break, resulting in severe or fatal personal injury.
Always check chain lubrication and the oil level in the tank
1
before starting work and periodically during work.
Never use waste oil to lubricate your STIHL saw chain and
guide bar. Repeated contact with waste oil can cause skin
cancer. Moreover, waste oil is environmentally harmful.
chain.
A properly adjusted chain will sit closely against the
underside of the guide bar but can still be pulled easily
along the bar by hand. Always wear gloves when handling
the chain.
tight.
– Reduce the tension by turning the adjusting wheel
counterclockwise until the saw chain can move freely
along the guide bar.
– Ensure that the drive links remain in the groove and that
the chain fits snugly against the underside of the guide
bar.
by hand to secure the chain sprocket cover.
WARNING
WARNING
15 Assembling the Chain Saw
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