GMC PCH25 Instruction Manual page 15

6. Make sure that the oil port is
not clogged. Grease the nose
sprocket at the tip of the
guide bar.
7. Check for fuel and oil leakage
and loose fastenings,
especially those securing the
handles and the guide bar. If
any defects are found, take
the tool to an authorised
repair centre.
8. Clean any dust away from the cooling vents as clogged
vents can cause overheating.
Chain sharpening
Sharpen the chain regularly to maintain optimum
performance of the saw. Signs of a dull chain are:
• The sawdust becomes powder-like
• Extra force is required to execute a cut
• The cut does not track in a straight line
• Increased vibration
• Increased fuel consumption
WARNING. Wear heavy
gloves when handling the chain.
Hold the guide bar (1) securely
in a vice.
Sharpen each cutter using a
chain file. Always use outward
strokes.
After sharpening, the cutters
must all have the same width and length. After every 3-4
times use an authourised repair centre to professionally
sharpen your saw chain. They have the special tools
necessary to ensure the correct cutting angles and depths.
Guide bar wear
Reverse the guide bar every 8 working hours to ensure
uniform wear. Check the bar rails frequently and if
necessary remove burs and square-up the rails using
a flat file.
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