Craftsman 151.98835 Operator's Manual page 23

TENSION TEST
■ Set the chain saw on a flat surface. Check
the chain tension by using one hand to lift the
chain above the edge of the bar. The tension
is correct when the chain lifts so that the tie
straps are approximately 3/32 - 5/32 inches
(2 - 4 mm) above the bar edge. (Figs.30)
■ Adjust the tension if the chain is too loose
or tight. Rotate the chain tensioning black ring
clockwise to tighten and counterclockwise to
loosen the chain tension.
NOTE: A cold chain is correctly tensioned
when there is no slack on the underside of
the guide bar, the chain is snug, and it can be
turned by hand without binding.
Retension a cold chain whenever the tie
straps on the drive links hang below the bar
bottom edge.
■ After tensioning chain, fully tighten the
chain cover red lock knob.
NOTE: During normal saw operation, the
temperature of the chain increases. The drive
links tie straps of a correctly tensioned warm
chain will hang approximately 1/16 in. (1.3
mm) below the bar bottom edge.
NOTE: New chains tend to stretch. Check
the chain tension frequently and tension as
required.
CAUTION! A chain tensioned while
warm may be too tight upon cooling.
Check the "cold tension" before next use.
CHECKING OIL LEVEL
■ Check the oil level at the window of the
oil tank (Quick View Oil Indicator) prior to
switching on and regularly during operation.
Refill oil when the oil level is lower than the
"MIN" marking. (Fig. 42)
■ Do not overfill. Leave approximately 1/5
inch of space to the lower edge to allow the
oil to expand. (Fig. 41)
■ Wipe up spilled oil with a soft cloth and refit
CARE AND MAINTENANCE
23 ― English
the tank cap.
■ Make sure the guide bar and the saw chain
are in place when you check the oil delivery.
■ Switch on the product (see section
"STARTING THE CHAINSAW" ); keep
pressing the trigger switch and check if the
chain oil is delivered as shown in the figure.
(Fig. 43)
CARE AND MAINTENANCE
■ Check the drive sprocket. If it is worn or
damaged due to strain, it must be replaced
before further chainsaw use.
■ Clear residue from the rails on the guide
bar using a screwdriver, putty knife, wire
brush or other similar tool. This will keep
the oil passages open to provide proper
lubrication to the bar and chain. (Fig. 44)
■ Check the guide bar 'rail' for wear: Hold a
ruler (straight edge) against the side of the
guide bar and 'cutter side plates'. If there is
a gap between the ruler and guide bar the
guide bar 'rail' is normal. If there is no gap
(ruler flush against the side of the guide bar)
the guide bar 'rail' is worn and needs to be
replaced with a new one of the same type.
(Fig. 45)
■ Reverse the guide bar from time to time
to allow for even wear, which will extend the
life span of the bar. Loosen the screw and
remove the tension disc from the guide bar.
Ensure the rubber washer on the screw is
free of wear. Turn the guide bar and fix the
tension disc with the screw. Apply a drop of
suitable glue to the screw to ensure its safe
positioning when reassembled. (Fig. 45a)