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7
NOTE:
•
No problem is caused even if the core bit unscrews
slightly during brief use since the core bit rotates in
the tightening direction.
To remove the core bit, follow the same removal proce-
dures covered in “When using the center bit”.
MAINTENANCE
CAUTION:
•
Always be sure that the tool is switched off and
unplugged before attempting to perform inspection
or maintenance.
Replacing carbon brushes
When the resin insulating tip inside the carbon brush is
exposed to contact the commutator, it will automatically
shut off the motor. When this occurs, both carbon
brushes should be replaced. Keep the carbon brushes
clean and free to slip in the holders. Both carbon brushes
should be replaced at the same time. Use only identical
carbon brushes.
Use a hex wrench to remove the rear cover.
Use a screwdriver to remove the brush holder caps. Take
out the worn carbon brushes, insert the new ones and
secure the brush holder caps.
Lubrication
This tool requires no hourly or daily lubrication because it
has a grease-packed lubrication system. It should be
relubricated after every 6 months of operation. Send the
complete tool to Makita Authorized or Factory Service
Center for this lubrication service. However, if circum-
stances require that you should lubricate it by yourself,
proceed as follows.
Run the tool for several minutes to warm it up. Switch off
and unplug the tool.
Remove the crank cap using a Makita lock nut wrench 35
(optional accessory). Rest the tool on the table with the
bit end pointing upwards. This will allow the old grease to
collect inside the crank housing.
Wipe out the old grease inside and replace with a fresh
grease (60 g; 2 oz). Use only Makita genuine hammer
grease (optional accessory). Filling with more than the
specified amount of grease (approx. 60 g; 2 oz) can
cause faulty hammering action or tool failure. Fill only
with the specified amount of grease.
Reinstall the crank cap and tighten with the lock nut
wrench.
CAUTION:
•
Do not tighten the crank cap excessively. It is made
of resin and is subject to breakage.
To maintain product SAFETY and RELIABILITY, repairs,
any other maintenance or adjustment should be per-
formed by Makita Authorized or Factory Service Centers,
always using Makita replacement parts.
ACCESSORIES
CAUTION:
•
These accessories or attachments are
recommended for use with your Makita tool
specified in this manual. The use of any other
accessories or attachments might present a risk of
injury to persons. Only use accessory or
attachment for its stated purpose.
If you need any assistance for more details regarding
these accessories, ask your local Makita Service Center.
•
Bull point
•
Cold chisel
•
Hammer grease
•
Depth gauge
1. Commutator
2. Insulating tip
3. Carbon brush
1. Hex wrench
2. Rear cover
1. Screwdriver
2. Brush holder
cap
1
2
3
001146
1
2
003225
1
2
003231
1. Lock nut wrench
2. Crank cap
1
2
003236