Makita BHP448 Technical Information page 4

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epair
[3] DISASSEMBLY/ASSEMBLY
[3] -2. Gear Assembly, Motor Section
DISASSEMBLING
After removing Drill chuck (Re: Figs. 1, 2, 3 and 4), disassemble Motor section and Gear assembly. (Figs. 8 and 9)
Fig. 8
1. Remove two 3x16 Tapping screws and Rear cover.
And remove four 4x18 Tapping screws.
3x16 Tapping
screw (2 pcs.) 4x18 Tapping
3. Pull out Heat sink section, and remove Gear assembly
together with Motor section and Speed change lever.
Motor section
Heat sink
section
5. Push Speed change lever assembly toward Motor side
until it stops to have space between the pin on the lever
of Gear assembly and rear Compression spring 4.
Motor side
rear
Compression
spring 4
Space between rear Compression spring 4
and the pin on the lever of Gear assembly.
Fig. 9
5. Shift the tail of Torsion spring from top of Carbon
brush to the Notch of Brush holder. Carbon brush
gets free from the pressure of Torsion spring.
Carbon brush
Note: Pay attention not to pinch your finger between Yoke unit and Armature when removing.
Rear cover
screw (4 pcs.)
Speed change lever
Gear assembly
Drill chuck side
front Compression spring 4 compressed
by the lever of Gear assembly
Torsion spring
Brush holder complete
Do not scratch the copper wires of Armature. Yoke unit draws Armature by its considerable
strong magnet force.
2. Remove Housing R, unscrewing
seven 3x16 Tapping screws.
4. Remove Speed change lever and Motor section
from Gear assembly.
Motor section
6. Lifting up Motor side of Speed change lever assembly,
pull it toward the direction designated with arrow.
Motor side
Pin on
the lever of
Gear assembly
6. From Armature, pull off Brush holder complete and Yoke unit.
P 4/ 12
3x16 Tapping screw (7 pcs.)
Speed change
lever assembly
Drill chuck side
Yoke unit
Armature