Komatsu PC290LC-6K Operation & Maintenance Manual page 255

When applying continuous impact to the same impact surface, if the
chisel does not penetrate or break the surface within 1 minute, change
the point of impact and carry out breaking operations closer to the edge.
The direction of penetration of the chisel and the direction of the
breaker body will gradually move out of line with each other, so always
adjust the bucket cylinder to keep them aligned.
Always keep the chisel pressed against the impact surface properly
to prevent using the impact force when there is no resistance.
MISTAKEN METHODS OF USE
To ensure that the machine has a long life, and to ensure that opera-
tions are carried out in safety, do not operate the machine in any of the
following ways.
• Do not operate the cylinder to the end of its stroke. Always leave
approx. 5 cm (2 in) to spare.
Using the mount to gather in pieces of rock
Operations using the swing force
30. EXTENDING MACHINE SERVICE LIFE
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