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6
Switch action (Fig. 6)
CAUTION:
Before plugging in the tool, always check to see that the
tool is switched off.
To start the tool, push the switch lever on the left side of
the tool. To stop the tool, push the switch lever on the
right side of the tool.
Speed change (Fig. 7)
The blows per minute can be adjusted between 950 and
1,900 BPM just by turning the adjusting dial. This can be
done even while the tool is running. The dial is marked 1
(lowest speed) to 6 (full speed). Refer to the table below
for the relationship between the number settings on the
adjusting dial and the blows per minute.
Chipping / Scaling / Demolition (Fig. 8)
Hold the tool firmly with both hands. Turn the tool on and
apply slight pressure on the tool so that the tool will not
bounce around, uncontrolled. Pressing very hard on the
tool will not increase the efficiency.
Indicator lamp (Fig. 9)
The green power-ON indicator lamp lights up when the
tool is switched ON. If the indicator lamp is lit but the tool
does not start, the carbon brushes may be worn out, or the
electric circuit or the motor may be defective. If the indica-
tor lamp does not light up and the tool does not start, the
ON/OFF switch or the mains cord may be defective.
The red service indicator lamp lights up when the carbon
brushes are nearly worn out to indicate that the tool
needs servicing. After approx. 8 hours of use, the motor
will automatically be shut off.
MAINTENANCE
CAUTION:
Always be sure that the tool is switched off and
unplugged before carrying out any work on the tool.
Replacement of carbon brushes (Fig. 10 & 11)
Whenever carbon brushes must be replaced, they cut out
the tool automatically. When this occurs, loosen the
screws which secure the rear cover. Pry up the rear cover
with a screwdriver and remove it. Then replace both car-
bon brushes at the same time. Use only identical carbon
brushes.
Lubrication
This tool requires no hourly or daily lubrication because it
has a grease-packed lubrication system. Lubricate the
tool every time the carbon brushes are replaced.
Run the tool for several minutes to warm it up. Switch off
and unplug the tool. Loosen the six screws and remove
the handle.
(Fig. 12)
Remove the crank cap using a socket wrench.
(Fig. 13)
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 (30 g). Use only Makita genu-
ine hammer grease (optional accessory). Filling with
more than the specified amount of grease (approx. 30 g)
can cause faulty hammering action or tool failure. Fill only
with the specified amount of grease. Reinstall the crank
cap and tighten with the socket wrench.
(Fig. 14)
CAUTION:
• Be careful not to damage the terminals or lead wires
especially when wiping out the old grease or installing
the handle.
• Do not tighten the crank cap excessively. It is made of
resin and is subject to breakage.
To maintain product safety and reliability, repairs, mainte-
nance or adjustment should be carried out by a Makita
Authorized Service Centre.
Number on
adjusting dial
Blows per minute
6
1,900
5
1,800
4
1,600
3
1,300
2
1,050
1
950