Hilti DD 150-U Mode D'emploi Original page 35

Malfunction
The diamond core bit doesn't
rotate.
The rate of drilling progress
decreases.
The hand wheel can be
turned without resistance.
The diamond core bit cannot
be fitted into the chuck.
Water escapes at the water
swivel or gear housing.
Water escapes at the chuck
during operation.
*2204401*
Possible cause
The diamond core bit has become
jammed in the hole.
Maximum drilling depth has been
reached.
The core is stuck in the core bit.
Wrong core bit specification for the
base material.
High steel content (indicated by
clear water containing metal cut-
tings).
The diamond core bit is defective.
Wrong gear selected.
Contact pressure is too low.
The machine has too little power.
The diamond core bit is polished.
The water flow rate is too high.
The water flow rate is too low.
The carriage lock is engaged.
Dust is hindering drilling progress.
The shear pin is broken.
The core bit connection end or
chuck is dirty or damaged.
The water pressure is too high.
The rotary shaft seal is worn out.
The diamond core bit isn't securely
tightened in the chuck.
2204401
Action to be taken
▶ Guide the diamond core drilling
machine in a straight line.
▶ Use an open-end wrench to
release the 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.
▶ If using a drill stand: Turn the
hand wheel and try to release
the diamond core bit by moving
the carriage up and down.
▶ Remove the core and use a core
bit extension.
▶ Remove the core.
▶ Select a more suitable diamond
core bit specification.
▶ Select a more suitable diamond
core bit specification.
▶ Check the diamond core bit
for damage and replace it if
necessary.
▶ Select the right gear.
▶ Increase the contact pressure.
▶ Select the next lower gear.
▶ Sharpen the diamond core bit
by drilling into a sharpening
plate.
▶ Reduce the water flow rate
by adjusting the water flow
regulator.
▶ Check the water supply to the
diamond core bit respectively
increase the water flow rate by
adjusting the water regulator.
▶ Release the carriage locking
mechanism.
▶ Use a suitable dust removal
system.
▶ Replace the shear pin.
▶ Clean and grease the connec-
tion end and/or the chuck or
replace these parts.
▶ Reduce the water pressure.
▶ Replace the rotary shaft seal.
▶ Tighten the diamond core bit
securely.
▶ Remove the diamond core bit.
Rotate the diamond core bit
approx. 90° about its own axis.
Refit the diamond core bit.
English 27