McCulloch Chain Saw Operator's Manual page 14

GENERAL SAFETY PRECAUTIONS
Check that the groove in the edge of the bar is clean.
Clean if necessary.
Check that the bar tip sprocket turns freely and that
the lubricating hole in the tip sprocket is not blocked.
Clean and lubricate if necessary.
If the chain lubrication system is still not working after
carrying out the above checks and associated measures
you should contact your servicing dealer.
Chain drive sprocket
The clutch drum is fitted with a Spur sprocket (the chain
sprocket is welded on the drum (D)). (4)
Regularly check the degree of wear on the drive sprocket.
Replace if wear is excessive. Replace the drive sprocket
whenever you replace the chain.
Checking wear on cutting equipment
Check the chain daily for:
Visible cracks in rivets and links.
Whether the chain is stiff.
Whether rivets and links are badly worn.
Replace the saw chain if it exhibits any of the points
above.
We recommend you compare the existing chain with a
new chain to decide how badly the existing chain is worn.
When the length of the cutting teeth has worn down to
only 5/32 inch (4 mm) the chain must be replaced. (10)
Guide bar
Check regularly:
Whether there are burrs on the edges of the bar (A).
Remove these with a file if necessary. (14)
Whether the groove in the bar has become badly worn
(B). Replace the bar if necessary. (14)
Whether the tip of the bar is uneven or badly worn. If
a hollow forms on the underside of the bar tip this is
due to running with a slack chain.
To prolong the life of the bar you should turn it over
daily.
A WARNING! Most chain saw accidents
happen when the chain touches the
operator.
Wear personal protective equipment, See
instructions under the heading "Personal
protective equipment".
Do not tackle any job that you feel you
are not adequately trained for. See
instructions under the headings
Personal protective equipment, How to
avoid kickback, Cutting equipment and
General working instructions,
Avoid situations where there is a risk of
kickback. See instructions under the
heading Machine's safety equipment.
Use the recommended protective
equipment and check its condition, See
instructions under the heading General
working instructions.
Check that all the chain saw safety
features are working. See instructions
under the headings General working
instructions and General safety
precautions.
-- a
14 - English 1154657-49 Rev.1 2012-03-15