
T
Description
ECHNICAL INFORMATION
Models No.
BFS440, BFS450
Cordless Screwdriver
PRODUCT
P 1/ 7
L
CONCEPT AND MAIN APPLICATIONS
Models BFS440 and BFS450 have been developed as a single-shot type
Cordless Screwdriver, featuring more convenience with one-touch locator
and LED job light.
These products are available in the following variations.
BFS440
Model No.
BFS440RFE
BFS440Z
BFS450
BFS450RFE
BFS450Z
Battery
type quantity
BL1430
(Li-ion 3.0Ah)
No No
BL1830
(Li-ion 3.0Ah)
No No
2
2
Charger
DC18RA
DC18RA
Plastic
carrying case
Yes
No
Yes
No
H
W
(The image above is BFS450.)
Dimensions: mm (")
Length (L) 258 (10-1/8)*1
Width (W)
Height (H)
*1. It differs by country.
Housing color
Makita-blue
Makita-blue All countries except North America
All countries except North America
Offered to
80 (3-1/8)
193 (7-5/8)
All models also include the accessories listed in "Standard equipment".
Specification
Specification
Voltage: V
Battery
Max output: W 235 325
Driver bit: mm (")
Capacities: mm (")
[drywall]
Reverse switch Yes
LED job light
Net weight*3: kg (lbs) 1.7 (3.8) 1.9 (4.2)
*2. 1.5Ah: Battery BL1415 or BL1815; 3.0Ah: Battery BL1430 or BL1830
*3. BFS440: includes battery BL1430; BFS450: includes battery BL1830
Capacity: Ah
Cell
Model
14.4 18
1.5 or 3.0*2
Li-ion
4,000No load speed: min.-1 = rpm
6.35 (1/4) HexShank
4 (5/32)Diameter
Yes
BFS450BFS440
Standard equipment
Phillips bit 2-25 ...................... 2
Belt clip ................................... 1
Note: The standard equipment for the tool shown above may differ by country.
Magnetic connect bit 6.35-60 (Magnetic connect bit 6.35-76) ...................... 1
Optional accessories
Phillips bit 1-25
Phillips bit 2-25
Phillips bit 3-25
Magnetic connect bit 6.35-60
Magnetic connect bit 6.35-76
Batteries BL1430, BL1415 (for BFS440)
Batteries BL1830, BL1815 (for BFS450)
Fast charger DC18RA
Charger DC24SA (for North America only)
Charger DC24SC (for all countries except North America)

P 2/ 7
[2] LUBRICATION
Apply Makita grease FA.No.2 to the following portions designated with the black triangle to protect parts and product
from unusual abrasion.
[1] NECESSARY REPAIRING TOOLS
CAUTION: Remove the bit and the battery from the machine for safety before
repair/ maintenance in accordance with the instruction manual!
Fig. 1
Repair
DescriptionCode No. Use for
Item No. Description Portion to lubricate Amount
4g
a little
a little
4g
Each depressed portion for Steel ball 4
Spindle
Clutch cam C
Gear complete 18-44
Armature
31
18
24
Shoulder pin 8-10
Flat washer 25 Whole portion
19
31
(a)
(c)
(a) The drum portion that contacts Plane bearing 14
(c) The portion that contacts 18 Spindle
(d) The Drum portion that contacts 24 Clutch cam C
(e) Teeth of the small gear that engages Helical gear 48
(f) Teeth of the large Gear that engages Armature's gear
(b) The Cam portion that contacts 24 Clutch cam C
(b)
(e)
(f)
Bearing extractor1R269 Removing Ball bearing 608
Plane bearing 14 Makita grease FA.No.2
24
20
21
20
21
18
19
(d)
Ball bearing 608
Helical gear 48
Steel ball 4.0

P 3/ 7
Repair
[3] DISASSEMBLY/ASSEMBLY
[3] -3. Locater Section
[3] DISASSEMBLY/ASSEMBLY
[3] -4. Helical Gear 48, Clutch Section
DISASSEMBLING
DISASSEMBLING
ASSEMBLING
Pull Lock ring strongly. Locater complete and Lock ring can be removed together.
When removing Locater base complete together with Locater complete and Lock ring, etc.:
1 Loosen 4x18 Tapping screws (2 pcs.) and remove Front cover.
2 Loosen M4x25 Pan head screw and pull Locater base complete. (Fig. 2)
Locator section can be removed as illustrated in Fig. 3.
Fig. 2
Fig. 4 Fig. 5
Fig. 3
Do the disassembling step in reverse.
Fig. 7Fig. 6
1
2
M4x25
Pan head screw
M4x25 Pan head screw
4x18 Tapping screws (2 pcs.)
Front cover
Locater base complete
Locater base complete
Leaf spring Ring spring 33 Dust seal ring
Brake pin
Lock ring
Lock ring
Locater complete
Locater complete
1) Pull Lock ring strongly. Locater complete and Lock ring can be removed together.
2) Loosen 4x18 Tapping screws (9 pcs.) and remove Housing R. (Fig. 4)
3) Separate an assembly of Helical gear 48 and Clutch cam, etc. (Fig. 5) from Housing L and remove Ball bearing 608
with 1R269.
4) Remove Leaf spring by hooking and turning it with Long nose pliers. (Fig. 6) Do not lose Steel ball 3.5 on Spindle.
The assembly (Re: Fig. 5) can be removed by hand as illustrated in Fig. 7.
Housing R
4x18 Tapping screws (9 pcs.)
Assembly of Helical gear 48 and Clutch cam, etc.
Leaf spring
Ball bearing
608
Steel ball 4
(3 pcs.)
Steel ball 4
O ring 18 Leaf spring
Helical
gear 48
Clutch cam C Compression spring 25 Shoulder pin 8-10
Long nose
pliers
Spindle
Ball bearing 608
Flat washer 26 Spindle Sleeve 20 Plane bearing 14Flat washer 25
(2 pcs.)

P 4/ 7
Repair
[3] DISASSEMBLY/ASSEMBLY
[3] -4. Helical Gear 48, Clutch Section (cont.)
ASSEMBLING
Fig. 9
Fig. 10
Fig. 11
Ball bearing 608
Steel ball 4
(3 pcs)
Steel ball 3.5
Clutch cam C
Helical gear 48
Assembly of Helical gear 48
Spindle
Shoulder pin 8-10
Flat washer 25 (2 pcs)
Sleeve 20
O Ring 18
Plane bearing 14
Gear complete 18-44
Plane bearing 5
(front)
Rubber sleeve 10
Plane bearing 5
(rear)
Flat washer 5
5) Assemble the parts illustrated below into Clutch section.
6) Assemble Gear section to Housing L.
Note: Do not forget to put Flat washer 5 between
Gear complete 18-44 and Plane bearing 5
(front).
4) Put each Steel ball 4 in the concave portion on the inside wall
of Clutch cam C.
Then assemble Clutch cam C to Helical gear 48.
Note:
Apply Makita grease FA.No.2 to the specific portions of
Spindle and Shoulder pin 8-10 illustrated in Fig. 1.
Fig. 8
1) Put Flat washer 26 on the flanged portion of
Clutch cam C.
Note: Make sure that there is no space between
Flat washer 26 and the flanged portion.
2) While turning Compression spring 25
in the direction of the arrow, push it down
until it touches Flat washer 26.
Compression spring 25
Flat washer 26
Clutch cam C
Taking the steps described in Fig. 8 to 11.
3) Apply Makita grease FA No.2 to
the inside wall of Clutch cam C
to prevent Steel Ball 4 (3 pcs.)
from falling off from Clutch cam C.

P 5/ 7
Repair
[3] DISASSEMBLY/ASSEMBLY
[3] -5. Motor Section
DISASSEMBLING
1) Remove Housing R (Fig. 4)
2) Disassemble Armature from the machine as illustrated in Figs. 12 and 13.
ASSEMBLING
Fig. 15Fig. 14
Your fingers will be pinched
and injured.
[Wrong][Correct]
Fig. 12
Fig. 13
12
Carbon
brush
Carbon
brush
Torsion
spring
1. Move the tail of Torsion spring
onto the notch of Brush holder.
2. Then pull off Receptacle from
Brush holder, then remove
Carbon brush.
Brush holder
complete
Yoke unit
Armature
1) Insert Armature into Yoke unit as described in Figs. 14 and 15.
2) Assemble Brush holder complete to the commutator end of Armature. (Fig. 12)
Because Yoke unit is a strong magnet, when assembling Armature
to Yoke unit, be sure to hold the commutator portion as illustrated
to left. Do not hold the Armature core as illustrated to right
or your fingers will be pinched between Yoke unit and the fan of
Armature that is pulled strongly by the magnet force.
Yoke unit is not reversible when assembled
to Armature.
Be sure to assemble so that the notch in
Yoke unit is positioned on the drive-end
of Armature.
If assembled wrong, the Motor section
cannot be assembled to Housing L.
[Wrong][Correct]
notch
Gear

P 6/ 7
Repair
[3] DISASSEMBLY/ASSEMBLY
[3] -5. Motor Section (cont.)
Fig. 16
ASSEMBLING
[3] -6. Switch
3) Assemble the Motor section to Housing L as illustrated in Fig. 16.
Put the projection on Switch between the prongs of F/R change lever,
then assemble the Switch to Housing L. (Fig. 17)
notch in Yoke unit Brush holder complete
groove
Housing L
rib
ASSEMBLING
With the projection on Housing L fitting in the notch on Yoke unit,
put Yoke unit inside the four ribs on Housing L.
Fig. 17
F/R change lever
Switch
projection
prong
1) Fit Brush holder complete in the groove
of Housing L.
2) The flat portion of Brush holder complete
must be at 90 degrees to the edge surface
of Housing L.
flat portion of Brush holder complete
edge surface of
Housing L
Housing L
Brush holder complete
viewed from Front cover side
90 degrees
Assembling Brush Holder to Housing L
projection
Assembling Yoke Unit to Housing L

P 7/ 7
Circuit diagram
Wiring diagram
Brush Holder
Complete
LED
Fig. D-1
Fig. D-2
Lead wires (red, black) of Brush holder complete
must be fixed with these lead wire holders.
Do not put any
Lead wire on
this rib to protect
from pinching.
Yoke unit
Circuit
Switch
Terminal
Color index of lead wires' sheath
Black
White
Red
Blue
Switch lead wires (red, black)
must be passed between rib A and rib B.
rib A
LED
rib B
Switch lead wires
(red, black) must be
fixed with these
Lead wire holders.
Brush holder
complete
Terminal
Switch
The flag connector must be so connected that
the wire connecting portion is positioned on
the side of pole marks of Terminal.
Flag connector
Terminal
Connecting Flag Connector
to Terminal
Wire connecting portion
Pole mark