Makita BTD140 Impact Driver User Manual


 
7
The fastening torque is affected by a wide variety of fac-
tors including the following. After fastening, always check
the torque with a torque wrench.
1. When the battery cartridge is discharged almost
completely, voltage will drop and the fastening
torque will be reduced.
2. Driver bit or socket bit
Failure to use the correct size driver bit or socket bit
will cause a reduction in the fastening torque.
3. Bolt
Even though the torque coefficient and the
class of bolt are the same, the proper fastening
torque will differ according to the diameter of
bolt.
Even though the diameters of bolts are the
same, the proper fastening torque will differ
according to the torque coefficient, the class of
bolt and the bolt length.
4. The manner of holding the tool or the material of
driving position to be fastened will affect the torque.
5. Operating the tool at low speed will cause a reduc-
tion in the fastening torque.
MAINTENANCE
CAUTION:
Always be sure that the tool is switched off and the
battery cartridge is removed before attempting to
perform inspection or maintenance.
Replacing carbon brushes
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.
Use a screwdriver to remove two screws then remove the
rear cover.
Raise the arm part of the spring and then place it in the
recessed part of the housing with a slotted bit screw-
driver of slender shaft or the like.
Use pliers to remove the carbon brush cap of the carbon
brushes. Take out the worn carbon brushes, insert the
new ones and replace the carbon brush cap in reverse.
Make sure that the carbon brush cap have fit into the
holes in brush holders securely.
Reinstall the rear cover and tighten two screws securely.
After replacing brushes, insert the battery cartridge into
the tool and break in brushes by running tool with no load
for about 1 minute. Then check the tool while running and
electric brake operation when releasing the switch trig-
ger. If electric brake is not working well, ask your local
Makita service center for repair.
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.
1. Limit mark
1. Rear cover
2. Screws
1
006258
1
2
006259
1. Spring
2. Arm
3. Recessed part
1. Carbon brush
cap
1. Hole
2. Carbon brush
cap
1
2
3
006260
1
006261
1
2
006304