Makita BFS441Z Manual

(The image above is BFS441.)
PRODUCT
CONCEPT AND MAIN APPLICATIONS
P 1/14
Specification
BFS441 , BFS451
Cordless Screwdriver
Models BFS441 and BFS451 are pistol grip Cordless Screwdrivers
with variable speed control switch, compact and lightweight body,
well balanced tool design for easy handling and maneuverability,
featuring the following main benefits:
Dimensions: mm (")
Width (W)
Height (H)
Length (L) 281 (11-1/8)*2
296 (11-5/8)*3
80 (3-1/8)
224 (8-7/8)*4
241 (9-1/2)*5
Specification
Weight according to
EPTA-Procedure 01/2003*6: kg (lbs)
1.4/ 1.6
(3.2/ 3.6)
1.5/ 1.7
(3.3/ 3.8)
Model BFS451BFS441
4 (5/32)Diameter
0 - 4,000No load speed: min.-1 = rpm
Driver bit: mm (")
Capacities: mm (")
[drywall]
LED job light
6.35 (1/4) HexShank
Yes
Reverse switch
Variable speed control by trigger
Yes
Electric brake Yes
Yes
Battery Cell
Voltage: V
Capacity : Ah
Energy capacity: Wh
Li-ion
14.4 18
1.3/ 3.0
Standard equipment
Optional accessories
Note: The standard equipment for
the tool shown above may vary
by country.
Phillips bit 2-25 ............................ 2
Magnetic connect bit
6.35-60 or 6.35-76 ........................ 1
Belt clip ........................................ 1
Models No.
Description
● Best possible tool body for screwdriving
● Compatible with both 1.3Ah and 3.0Ah batteries
● Single LED job light with afterglow function
19/ 44 24/ 54
*6: With Battery
*2: with Magnetic connect bit 60
*3: with Magnetic connect bit 76
*4: with BL1415 or BL1815
*5: with BL1430 or BL1830
Phillips bit 1-25
Phillips bit 2-25
Phillips bit 3-25
Magnetic connect bit 6.35-60
Magnetic connect bit 6.35-76
Battery BL1415 for BFS441
Battery BL1430 for BFS441
Battery BL1815 for BFS451
Battery BL1830 for BFS451
Fast charger DC18RA
Charger DC24SC (for all countries
except North American countries)
Charger DC18SD
Automotive charger DC18SE
BFS441
Model No. Type Quantity Charger Plastic
carrying case
Battery
cover
Battery
BL1430 DC18RA NoYes
BFS441Z
2 1
BFS441ZX
BFS441RFE
BL1430 DC18RA YesNo
2 1BFS441RFX
All models also include the accessories listed below in "Standard equipment".
No No NoNoNo No
No No YesNoNo No
BFS451
Model No. Type Quantity Charger Plastic
carrying case
Systainer
case
Systainer
case
Battery
cover
Battery
BL1830 DC18RA NoYes
BFS451Z
21
BFS451ZX
BFS451RFE
BL1830 DC18RA YesNo
2 1BFS451RFX
No No NoNoNo No
No No YesNoNo No
Charging time (approx.): min. 15/ 22 with DC18RA
TECHNICAL INFORMATION
L
H
W
This model is available in the following variations.
OFFICIAL USE
for ASC & Sales Shop

P2/14
Repair
CAUTION: Repair the machine in accordance with “Instruction manual” or “Safety instructions”.
[1] NECESSARY REPAIRING TOOLS
[2] LUBRICANT AND ADHESIVE APPLICATION
Fig. 1
Code No. Description Use for
1R269 Bearing extractor (small) removing Ball bearing 608ZZ
Item No.
Apply the following lubricants to protect parts and product from unusual abrasion. (Fig. 1)
Description Lubricant
VG32
3g
a little
a little
a little
a littleVG100
AmountPortion to lubricate
7
4
3
10
11
Clutch cam
X ring 14
Apply adhesive ThreeBond 1215 to the ribs surrounding gear room of Housing (L) complete. (Fig. 2)
Steel ball 4
18
18A
18A
18B
18B
Compression
spring 25
3Locator complete Thread portion
4
Makita
grease
FA No.2
Internal surface
Internal surface
7 Locator base Internal surface of Dust seal 13 that Spindle 125S
complete contacts
10 Spindle 125S complete Surface that Clutch cam contacts
11 Flat washer 25 Surface that Compression spring 25 contacts
17 Bearing complete
Gear complete Teeth portion
Concave for Steel ball 4
17
18
Dust seal sleeve
Dust seal 13
Fig. 2
Housing (L) complete
Apply 1g “ThreeBond 1215”
on the ribs surrounding gear room.
ribs
Apply the bond up to
the end of the ribs.

P3/14
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-1. Locator Section
DISASSEMBLING
1. Pull off Locator complete and Lock ring from Housing,
then remove Locator complete from Lock ring.
Locator complete
Lock ring
Leaf spring
Fig. 3
2. Remove Leaf spring with
slotted screwdriver.
3. Remove Rubber plate from
Housing (L) complete.
4. Mount Locator complete back
to Locator base complete.
Rubber plate
Remove Seal ring 30
from Lock ring
Remove Dust seal sleeve
from Locator complete.
Remove ring spring 33
from Locator base complete.
Housing (L) complete
Locator base complete
5. Grip flat portion of Locator complete with
adjustable wrench, then turn it clockwise
to remove Locator base complete from Housing.
Locator base
complete
Ring spring 33
Locator
complete
Locator complete
Dust seal sleeve
Lock ring
Ring spring 33
Seal ring 30 Locator base complete

P4/14
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-1. Locator Section
ASSEMBLING
Rubber plate
1) Assembling of Locator base complete, Locator complete, Leaf spring and related parts. (Fig. 4)
1. Mount Locator complete to Locator base complete and fix them
to Housing set by tightening counterclockwise with adjustable wrench.
2. Remove Locator complete again,
then put Rubber plate in place.
Locator base complete
Locator base complete
Locator complete
3. Fit the tab of Leaf spring to Housing top as described below, then fix the other tab of Leaf spring to
Housing bottom with pliers.
4. Fix Ring spring 33 in the groove on Locator base complete as described below.
tab of
Leaf spring
Locator complete
Ring spring 33
Ring spring 33
Fig. 4
Locator base
complete
protrusion on
Housing top protrusion on
Housing bottom

P5/14
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-1. Locator Section
ASSEMBLING
2) Make sure to put Seal ring 30 in Lock ring and Dust seal sleeve in Locator complete
before mount them on Housing. (Fig. 5)
Dust seal sleeve
Seal ring 30
Lock ring Locator complete
Fig. 5
Locator complete
Lock ring
Fig. 6
3) Insert Locator complete into Lock ring and mount them on Housing. (Fig. 6)

P6/14
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-2. Clutch Section
DISASSEMBLING
1. Dismantle Housing (R) complete by removing
seven 4x18 Tapping screws.
2. Holding Spindle top and Ball bearing 608ZZ
with Flat washer 14 as shown below,
remove Clutch section.
Flat washer 26
Gear complete
Gear complete
Flat washer 25 ( 2 pcs.)
X Ring 14
Bearing complete
Spindle 125S
complete
Compression
spring 25 Clutch cam 125S
Fig. 7
Fig. 8
3) Disassembling of Clutch section (Fig. 8).
4) Spindle 125S, Clutch cam 125S and Gear complete can be disassembled as described below (Fig. 9).
1) Disassemble Locator section (Fig. 3) and remove Magnetic connect bit from Spindle 125S.
2) Separate Spindle section from Housing L (Fig. 7).
Housing (R)
complete
4x18 Tapping
screw ( 7 pcs.)
Spindle 125S
complete
Ball bearing
608ZZ
Flat washer 14
Flat washer 14
1R269
Ball bearing
608ZZ
Bearing complete
Spindle 125S completeSteel ball 3.5
Remove Leaf spring and Steel ball 3.5.
Bearing complete can now be removed from
Spindle 125S complete.
Remove Ball bearing 608ZZ
from Gear complete with 1R269.
Remove Steel ball 4 (3 pcs)
from Clutch cam 125S.
Steel ball 4
(3 pcs.)
Leaf spring
Clutch cam 125S
Fig. 9
Note: Housing (R) complete may not be easily removed
as it is adhered to Gear room ribs with
“ThreeBond 1215”. (Fig. 2)
Bearing complete Spindle 125S complete

P7/14
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-2. Clutch Section
ASSEMBLING
1. Fix Flat washer 26 on the flange portion of Clutch cam 125S, then mount
Compression spring 25 on it.
Fig. 10
1) Assemble the component parts to Clutch cam 125S. (Fig. 10)
2) Assemble Gear complete, Spindle 125S complete and Bearing complete. (Fig. 11)
3) Assemble the Clutch section to Housing (L) complete. (Fig. 12)
flange portion
Flat washer 26
Clutch cam 125S
Fig. 11
Fig. 12
Compression
spring 25
Clutch cam
Gear complete
Compression spring 25
Flat washer 25
1. Apply Makita grease FA No.2 to the
whole portion of the Flat washers.
3. Mount Bearing complete to the Spindle,
then fix Steel balls with Leaf spring.
Leaf spring
Steel ball 3.5
Bearing
complete
Assemble Clutch section and Housing (L) complete together
by engaging the protrusion of Bearing complete in the depression
of Housing (L) complete while holding Flat washer 14 and Spindle top
as shown above.
Ball bearing 608ZZ
Flat washer 14
Spindle 125S complete
protrusion of
Bearing complete
depression
Housing (L)
complete
Clutch cam 125S
2. Apply Makita grease FA No.2
in Clutch cam 125S,
then put Steel ball 4 in place.
2. Apply “VG32” on the contact surface with
Compression spring 25 in addition to
Makita grease FA No.2, then assemble
the parts as shown above.
Spindle

P8/14
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-3. Motor Section (Armature, Yoke unit, Brush holder)
ASSEMBLING
1. Remove Motor section (Armature, Yoke unit,
Brush holder) from Housing (L) complete.
Fig. 13
1) Disassemble Locator section (Fig. 3) and remove Magnetic connect bit from Spindle 125S.
2) Separate Housing (R) complete (Fig 7).
3) Disassemble Motor section from Housing (L) complete. (Fig. 13)
Armature
Brush holder
Yoke unit
Housing (L) complete
Armature
2. Shift the tail of Torsion spring from top of Carbon
brush to the notch of Brush holder.
Carbon brush is now free from the pressure of
Torsion spring.
tail of
Torsion spring
Carbon
brush
Yoke unit
tail of
Torsion spring
notch
Yoke unit
Armature
Carbon
brush
3. Remove Carbon brushes from Brush holder. 4. Pull off Brush holder complete from Armature.
Carbon
brush
Carbon brush
Brush holder
complete
5. Pull off Armature from Yoke unit.
Note:
Carefully remove Armature so as not
to damage magnet wire because Armature
will be pulled towards Yoke unit with
strong magnetic force of Yoke unit.
Brush holder

P9/14
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-3. Motor Section (Armature, Yoke unit, Brush holder)
ASSEMBLING
Fig. 14
1) Assemble Motor section as described in Fig. 14.
1. Insert Armature into Yoke unit
in the direction of the arrow.
2. Mount Brush holder complete
to Armature.
notch
Note:
The notch on Yoke unit must be
positioned on the Armature fan side.
notch Brush holder
complete
Yoke unit
3. Assemble Motor section to Housing (L) complete by engaging the notch of Yoke unit
to the protrusion of Housing (L) complete. Then make sure that Yoke unit and
Brush holder complete are exactly mounted to Housing (L) complete. (Fig. 14A, 14B)
notch
Yoke unit
Yoke unit must be
exactly set between
these ribs.
protrusion
Housing (L) complete
Terminal
Yoke unit
The flat portion of Brush holder complete must be at right angle
vertically as shown below when it is mounted to Housing (L)
complete.
Brush holder
complete
Housing (L)
complete
flat portion of
Brush holder complete
90 degrees
Fig. 14A Fig. 14B
Note:
Carefully insert Armature to Yoke unit
so as not to damage magent wire
or pinch your finger because Armature
will be pulled towards Yoke unit with
strong magnetic force of Yoke unit.

P10/14
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-4. F/R Change Lever
ASSEMBLING
Fig. 15
Be sure to mount F/R change lever on Switch before assembling Housing (R) complete. (Fig. 15)
F / R change Lever
projection
fork portion
Engage this fork portion with
the projection on Switch.

Circuit diagram
Fig. D-1
White
Orange
Blue
Yellow
Color index of lead wires' sheath
Black
Red
Light circuit
Connectors
Heatsink
FET
Terminal
LED job light
Switch
Brush holder complete
Line filter
Note:
Use two Line filters in the following positions
if required.
* Between Switch and Brush holder complete
* Between Switch and Terminal
Line filter
P 11/14
Red for BFS441
White for BFS451

Wiring diagram
P12/14
Fig. D-2
Fig. D-3
Wiring of Brush Holder Complete
Wiring of Switch
FET Lead wire (black)
FET Lead wire (blue)
FET Lead wire (yellow)
Heatsink
FET
for connecting to
Switch terminal M1.
Brush holder complete and Switch unit come with Line filter as complete unit
for the countries requiring Line filters (Fig. D-2, D-3).
for connecting to
Switch terminal M2.
for connecting
to Connector
of Light circuit
Fix the FET Lead wires in
these Lead wire holders
on Switch in the order of:
1) yellow, 2) blue, 3) black
from the Switch trigger side.
Wind Lead wires (black, red)
once on Line filter.
Line filter
Brush holder complete
Pass Lead wires (black, red)
through Line filter.
Switch

Wiring diagram
P13/14
[Correct]
Lead wire of Carbon brush
Route the Lead wire here.
Torsion spring
tail of Torsion spring
tail of Torsion spring
Route the Lead wire
through this slot.
[Wrong]
Wrongly routed Lead wire
may interfere the tail of
Torsion spring.
Installing and removal of Carbon brush. (Figs. D-4, D-5)
Fig. D-4 Fig. D-5
Setting Carbon brush

Wiring diagram
P14/ 14
Connectors
Switch trigger
Switch
rib FET
Brush holder complete
Light circuit
LED job light
90 degrees
Terminal
rib
Wiring in Housing (L) Complete
Fig. D-5
Top line of Switch
[Wrong]
[Correct]
LED job light
Lens of LED must be
parallel to the opening
of the LED mounting hole
in order to illuminate
worksurface exactly.
Worksurface
is bright.
Light
LED is unable to illuminate
worksurface if installed
upside-down.
LED job light
Worksurface
is dark.
Light
Note: Install LED job light at the correct angle.
Connect Terminals from Brush holder
complete to Switch at the right angle
to the top line of Switch.
Do not put lead wires on this rib
to avoid pinching.
Fix Lead wires from
Connectors in these
Lead wire holders.
Route Lead wires from Switch
(black, red, white) through
the space between the rib and
Light circuit.
Fix the Lead wires of
LED job light in this
Lead wires holder.