17
Special Cold Weather Care
If a chain is tensioned in very cold weather, it will sag
when it reaches the normal operating temperature. Always
keep the chain tension tight while cutting and loosen it
after operation, or it will cool, contract and break, possibly
damaging the bar, the crankshaft, and the bearings.
At extremely low temperatures, normal chain oil will
“set” (become too thick to flow). A winter grade bar and
chain oil may be used.
Increase the oil flow while cutting in cold weather.
Cutting frozen wood increases friction on both the cutters
and tie straps, and can cause them to crack.
WARNING
Kickback
Kickback may occur when the moving saw chain near
the upper quadrant of the bar nose contacts a solid
object or is pinched. The reaction of the cutting force
of the chain causes a rotational force on the chain saw
in the direction opposite to the chain movement. This
may fling the bar up and back in an uncontrolled arc
mainly in the plane of the bar. Under some cutting
circumstances the bar moves towards the operator,
who may suffer severe or fatal injury.
To reduce the risk of kickback:
• Hold the chain saw firmly with both hands.
• Don’t overreach.
• Don’t let the nose of the guide bar contact a log, a
branch, the ground, or any other obstruction.
• Cut at high engine speeds.
• Don’t cut above shoulder height.
• Follow manufacturer’s sharpening and maintenance
instructions for the saw chain.
• Use devices such as low kickback chain, which may
help to reduce the hazards associated with kickback.
16
Condition:
Peening or premature flattening on bottom of cutters
and tie straps.
Cause:
Loose chain tension. Dull cutters. Lack of lubrication.
Chain has been forced to cut.
Remedy:
Chain must be replaced if badly worn. Check chain
tension and cutter sharpness more frequently.
Condition:
Burring and peening in notch of tie strap.
Cause:
Worn chain sprocket.
Remedy:
Replace sprocket and chain.
STIHL Sharp Advice rdsp 110606 11/6/06 4:16 PM Page 19
