G D C 4 C O R E D R I L L
10
Troubleshooting
Note
SERVICING SHOULD ONLY BE DONE BY A QUALIFIED TECHNICIAN.
DON’T FORGET TO POWER DOWN UNIT PRIOR TO SERVICE!
PROBLEM
SOLUTION
Motor does not
turn on.
1) Check fuel level.
2) Fuel Filter is clogged. Replace filter.
3) Check oil level.
4) Check air filter is clean.
5) Motor carburetor needs cleaning.
6) Loose internal wire. Check and secure if necessary.
7) Spark plug issue. Inspect/replace if necessary.
8) Check to ensure the motor on/off switch is operable. Replace if
necessary.
Hole is not
cutting.
1) Cutting bit is dull. Replace bit.
2) Work area material is not appropriate for bit type.
Bit is jammed
while coring.
1) Debris is lodged between core hole and bit. Rotate bit in both
directions to and inspect bit for debris.
Coring speed has
reduced.
1) Bit has hit rebar. Adjust feed pressure to prevent motor overload while
cutting through rebar.
2) Diamonds on bit have glazed over. Deglaze bit or dress diamond rim on
bit and check water flow rate.
3) Diamonds on bit have worn away. Replace core bit.
4) New core bit. Core at slow rate with new bits for 2-3 coring cycles.
5) The safety clutch is slipping. Inspect and assess clutch condition.
6) DRY type drilling progress is prevented by an accumulation of dust.
Use suitable vacuum cleaner.
7) Water flow rate is too low. Increase water flow.
8) Core is stuck in the core bit. Remove core.
Core bit appears
to wobble.
1) Spindle is damaged. Replace spindle and check bearings.
2) Bit is bent or damaged. Replace bit.
3) The core bit is not screwed securely onto the spindle.
4) Coring material is attaching to the bit. Inspect bit and increase water
flow rate.
Water escapes at
the water swivel
or gear housing.
1) The water pressure is too high. Turn down water flow.
2) The shaft seal is defective. Replace seal
3) The water hose is damaged. Replace hose.
Chapter
4
