Trouble or fault
The diamond core bit doesn't
rotate.
The drilling speed is decreas-
ing.
The handwheel can be turned
without resistance.
Water escapes at the water
swivel or gear housing.
The diamond core bit can't be
fitted into the chuck.
9
Disposal
Most of the materials from which Hilti tools and appliances are manufactured can be recycled. The
materials must be correctly separated before they can be recycled. In many countries, your old tools,
machines or appliances can be returned to Hilti for recycling. Ask Hilti Service or your Hilti representative
for further information.
*434951*
Printed: 09.08.2019 | Doc-Nr: PUB / 5069586 / 000 / 08
Possible cause
The diamond core bit has become
jammed in the base material.
The gearing is defective.
The diamond core bit is polished.
Wrong core bit specification for the
base material.
The water flow rate is too high.
The core is stuck in the diamond
core bit.
Maximum drilling depth has been
reached.
The diamond core bit is defective.
Safety clutch disengages too soon
or is slipping.
The brake has been applied.
The water flow rate is too low.
High steel content (indicated by
clear water containing metal cut-
tings).
The split pin is broken.
The water pressure is too high.
The rotary shaft seal is worn out.
The core bit connection end or
chuck is dirty or damaged.
434951
Action to be taken
▶ Use an open-end wrench to
release the diamond core bit:
Disconnect the supply cord plug
from the power outlet. Grip the
diamond core bit with a suitable
open-end wrench close to the
connection end and release the
diamond core bit by rotating it.
Stand-guided drilling
▶ Turn the handwheel and try to
release the diamond core bit
by moving the carriage up and
down.
▶ Have the machine repaired by
Hilti Service.
▶ Sharpen the diamond core bit
by drilling into a sharpening
plate.
▶ Select a more suitable diamond
core bit specification.
▶ Reduce the water flow rate
by adjusting the water flow
regulator.
▶ Remove the core.
▶ Remove the core and use a core
bit extension.
▶ Check the diamond core bit
for damage and replace it if
necessary.
▶ Have the machine repaired by
Hilti Service.
▶ Release the brake.
▶ Check the water supply to
the diamond core bit or,
respectively, increase the water
flow by adjusting the water flow
regulator.
▶ Select a more suitable diamond
core bit specification.
▶ Replace the split pin.
▶ Reduce the water pressure.
▶ Replace the rotary shaft seal.
▶ Clean and grease the connec-
tion end and/or the chuck or
replace these parts.
English
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