Replacing Carbon Brushes; Maintenance - Makita 7104L Instruction Manual

2. Longitudinal (length) enlargement
Hole length can be determined in three steps shown in the
table below.
Cutter chain position
Original position
No.1 set position
No.2 set position
NOTE:
• A hole a little longer than predetermined may be cut
depending upon the cutter chain tension.
• The adjusting hex bolts are factory adjusted for cutting
holes 90 mm long in the No. 1 set position and 120 mm
long in the No. 2 set position.
Push down the right-hand grip while raising the left-hand
grip. Make sure that the adjusting hex bolt slips into place
securely. (Fig. 11)
Loosen the hex nut securing the adjusting hex bolt. Turn
the adjusting hex bolt until the cutter chain reaches the
desired position, then tighten the hex nut.
WARNING:
• When using pressure to turn the adjusting hex bolt or
hex nut, be careful not to allow the adjusting hex bolt to
slip off the set position.
To bring the cutter chain back to the perpendicular (origi-
nal) position, pull the lever (C) toward you while pressing
down on the right-hand grip and slightly raising the left-
hand grip and move the cutter chain back to its original
position. (Fig. 12)
When cutting a hole, first use the perpendicular position,
then No.1 set position and finally No.2 set position.
Always safely hook the tool head back onto the hook
when changing the cutter chain position. (Fig. 13)
When enlarging a hole both transversely and longitudi-
nally, cut the holes in the order indicated from No. (1) to
(6) as shown. This makes for more easy and efficient hole
enlargement. (Fig. 14)
WARNING:
• Never attempt to enlarge a hole with the cutter chain
still within the hole. This will cause unstable and dan-
gerous operation.
• Never angle the cutter chain when cutting the first hole,
or a dangerous kickback may result. Always have the
cutter chain set to the perpendicular position when cut-
ting the first hole.
Lap joints up to 130 mm can be cut with this tool. (Fig. 15)
NOTE:
• Lap joints can be cut only on the front (side away from
you) of the workpiece.

MAINTENANCE

CAUTION:
• Always be sure that the tool is switched off and
unplugged before attempting to perform inspection or
maintenance.
Hole length to be cut
52.5 mm
52.5 mm – 105 mm
77.5 mm – 130 mm

Replacing carbon brushes

Remove and check the carbon brushes regularly. Replace
when they wear down to the limit mark. 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. (Fig. 16)
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. (Fig. 17)
Lubrication
After use, remove dirt, chips and foreign matter adhering
to the tool. Then oil the moving parts (especially cutter
chain) and the contact portions.
To maintain product SAFETY and RELIABILITY, repairs,
any other maintenance or adjustment should be per-
formed by Makita Authorized 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.
• Cutter chain
• Chain bar for 30 mm
• Sprocket 4 for 30 mm
• Oil supply (100 cc)
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