Makita DGA404 Manual

The subject models are cordless angle grinders powered by 18V Li-ion battery,
and equipped with highly enhanced Brushless DC motor compared to the current
models DGA402/ DGA452.
A built-in controller changes the cutting speed automatically according to load condition,
enabling users to obtain high speed rotation on light duty application/ high torque on
heavy duty application.
Models No.
Description
PRODUCT
TECHNICAL INFORMATION
CONCEPT AND MAIN APPLICATIONS
Specification
Standard equipment
Optional accessories
P 1/ 14
Dimensions: mm (")
DGA404
All
Width (W) DGA454
Length (L)*1 362 (14-1/4)
117 (4-5/8)
130 (5-1/8)
DGA504
DGA404
Height (H)
140 (5-1/2)
140 (5-1/2)
DGA454,
DGA504 145 (5-3/4)
Note: The standard equipment may vary by country or model variation.
DGA404, DGA454, DGA504
18V Cordless Angle Grinders L
H
W
Specification Model DGA404
18
Weight according to
EPTA-Procedure 01/2003: kg(lbs)*22.5 (5.5) 2.5 (5.6)2.4 (5.3)
Battery
1.5, 2.0, 3.0, 4.0, 5.0Capacity: Ah
Voltage: V
Li-ionCell
Energy capacity: W 27, 36, 54, 72, 90
Charging time (approx.): min. 15, 18, 22, 36, 45 with DC18RC
Wheel size: mm (") Hole diameter
6 (1/4)Max. thickness
Diameter 100 (4)
16 (5/8) 22.23 (7/8)
8,500
No
Yes
Yes
Yes
Yes
Yes
No load speed: min.ֿ ¹= rpm
Slide
Switch type
Electronic control
Overload warning lamp
Electronic current limiter
Soft start
Anti-restart function
Battery fuel gauge
Soft grip
*2 With 3.0Ah battery
*1 With BL1830/ BL1840/ BL1850
Note: BL1815 is not compatible.
DGA504DGA454
115 (4-1/2) 125 (5)
Lock nut wrench ............................................ 1
Side grip ......................................................... 1
Depressed center grinding wheel ................... 1 (100mm for DGA404, 115mm for DGA454, 125mm for DGA504)
Battery cover .................................................. 1 (except -Z- model)
Plastic carrying case ....................................... 1 (except -Z- model)
Charger DC18RC ........................................... 1 (except -Z- model)
Li-ion battery BL1830 or BL1840 ................. 2 (except -Z- model)
Depressed center wheels
Rubber pads
Abrasive discs
Wire brushes
Diamond wheels
Abrasive cut off wheels
Toolless wheel covers
Sanding lock nuts
Fast charger DC18RC
Fast charger DC18SD
Charger DC24SC
Automotive charger DC18SE
Four port multi charger DC18SF
Li-ion battery BL1815N
Li-ion battery BL1820
Li-ion battery BL1830
Li-ion battery BL1840
Li-ion battery BL1850
OFFICIAL USE
for ASC & Sales Shop

Repair
P 2/ 14
CAUTION: Repair the machine in accordance with “Instruction manual” or “Safety instructions”.
[1] NECESSARY REPAIRING TOOLS
[2] LUBRICATION
Code No. Description Use for
1R045 Gear extractor (large) removing Rotor
1R027 Bearing setting pipe ø18-ø10.2 pressfitting Rotor
1R029 Bearing setting pipe ø23-ø15.2 pressfitting Spiral bevel gear 37
1R004 Retaining ring pliers ST-2 removing/ assembling Ring spring 11
1R034 Bearing setting plate ø12.2
1R258 V block removing Spiral bevel gear 37
1R291 Retaining ring S and R pliers removing Retaining ring R-32
Round bar for arbor ø12-50 removing Ball bearing 629LLB1R286
Round bar for arbor ø6-50 removing Spiral bevel gear 371R280
Bearing extractor (small) removing Ball bearing 607LLB/ 696ZZ1R269
Spring pin extractor M3 disassembling Shaft lock mechanism1R268
Item No. Description Lubricant Amount
9g
a little
Portion to lubricate
O ring 26
Spiral bevel gear 10
7
5
Apply the following grease to protect parts and product from unusual abrasion. (Fig. 1)
Gear teeth in the gear room of Gear housing
Inner periphery that appears from Gear housing cover
Fig. 1
Makita
grease
SG. No.0
5
Gear housing cover
7
Gear housing

DISASSEMBLING
Repair
P 3/ 14
(1) Remove Gear housing cover with Rotor section from Motor housing. (Figs. 2, 3 and 4)
(2) Disassemble Rotor section. (Fig. 5)
Remove four 4x30 Tapping screws.
Fig. 2
4x30 Tapping
screw (4 pcs.)
4x30 Tapping screw (4 pcs.)
Gear housing
Gear housing
Bearing box
Bearing boxGear housing cover
Fig. 5
Fig. 3
[3] DISASSEMBLY/ASSEMBLY
[3]-1. Rotor, Ball bearing 629LLB/ 607LLB, Spiral bevel gear 10
Remove the assembled part of Gear housing and Bearing box
from Gear housing cover.
While holding Rotor by a gloved
hand, turn M6 Hex nut counter-
clockwise with a Wrench 10.
Wrench 10
M6 Hex nut
Rotor
Rotor
Gear housing cover
Spiral bevel gear 10
M6 Hex nut
Fig. 4
Thin slotted screwdriver
(First, turn it carefully to enlarge the gap
between Gear housing cover and Motor housing,
then pry off Gear housing cover with Rotor section.)
Groove to insert a thin slotted screwdriver
Insert a thin slotted screwdriver into the groove of Gear housing cover, and
remove Gear housing cover from Motor housing.
Gear housing cover
Motor housing

DISASSEMBLING
Repair
P 4/ 14
Fig. 6
Fig. 7
[3] DISASSEMBLY/ASSEMBLY
[3]-1. Rotor, Ball bearing 629LLB/ 607LLB, Spiral bevel gear 10 (cont.)
Hook the jaws of 1R045 with Gear housing cover, then push out Rotor.
Remove Ball bearing 607LLB* from Rotor with 1R269.
* The component of Rotor
Press down Ball bearing 629LLB
with 1R286.
1R045
Rotor
Gear housing cover
Gear
housing cover
(3) Disassemlble Gear housing cover and Rotor section. (Figs. 6 and 7)
1R286
Arbor
press
Ball bearing
629LLB
Ball bearing 607LLB
1R269
Rotor
When handling or storing multiple Rotors, be sure to keep a proper distance between Rotors as shown in Fig. 8
because Rotor is a strong magnet, failure to follow this instruction could result in:
• Finger injury caused by pinching between Rotors pulling each other.
• Magnetic loss of Rotors or damage on the magnet portion of Rotor.
(Fig. 9)
Fig. 8 Fig. 9
* Magnetic loss of Rotors
* Damage on the magnet
portion of Rotor
Right Wrong
A proper distance
between Rotors
Caution for Handling of Rotor

ASSEMBLING
Repair
P 5/ 14
Fig. 10
Fig. 11
[3] DISASSEMBLY/ASSEMBLY
[3]-1. Rotor, Ball bearing 629LLB/ 607LLB, Spiral bevel gear 10 (cont.)
When you assemble Rotor with Gear housing cover to Motor housing,
the magnetic force of Rotor toward Stator returns Gear housing cover
back to the original position.
Therefore, be careful not to pinch your fingers between Motor housing
and Gear housing cover.
Face the groove of Gear housing cover and Spindle toward the opposite
of Switch knob.
Fig. 12
Assemble by reversing the disassembly procedure.
Note: Be careful about the points shown in Figs. 10, 11 and 12.
Gear housing
cover
Motor housing
Switch knob
Groove of Gear housing cover Spindle
Receive the inner race of Ball bearing 629LLB in Gear housing cover with 1R027,
and pressfit the shaft of Rotor into the hole of Ball bearing 629LLB.
Arbor press
Rotor
1R027
Gear housing
cover
Gear housing
cover
O ring 26
with Grrease SG No. 0
on the inner periphery
Ball bearing 629LLB
1R027
Hole of Ball bearing 629LLB

DISASSEMBLING
Repair
P 6/ 14
Note: The subject parts can be removed without disassembling Motor section.
Disassemble Bearing box section as drawn in Fig. 13 to Fig. 19.
Fig. 13
Fig. 15
Fig. 17
Fig. 19
Fig. 18
Fig. 14
[3] DISASSEMBLY/ASSEMBLY
[3]-2. Spiral bevel gear 37, Ball bearing 696ZZ and Ball bearing 6201DDW
Remove four M4x14
Pan head screws and
Bearing box from
Gear housing.
Remove Ball bearing
696ZZ with 1R269.
While opening Ring spring 11 with 1R004, pry and
remove it from Spindle with a slotted screwdriver.
Pry up Open
1R004
Slotted
screwdriver
Fig. 16
Arbor press
Spindle
Spiral bevel
gear 37
1R258
Bearing box
Press down Spindle with 1R280.
Remove Retaining ring R-32 from
Bearing box with 1R291
Bearing box section can be disassembled. Be careful about each position and the direction of Labyrinth ring
Note: When Spindle is removed from Spiral bevel gear 37, Ball bearing 6201DDW has a damage during the removal
process. Therefore, replace Ball bearing 6201DDW with a new one.
Spindle Labyrinth ring
M4x14 Pan head
screw (4 pcs.)
Bearing box Ball bearing
6201DDW
O ring 45 Ball bearing 696ZZFlat washer 12
Ring spring 11
Spiral bevel gear 37Retaining ring
R-32
Arbor press
1R280
Spindle
1R258
Spiral bevel
gear 37
Bearing box
Receive Bearing box on 1R258.
Provide an impact to Spindle carefully with Arbor press so that Arbor press
does not touch Spiral bevel gear 37
and Spindle sinks slightly.
1R291 Retaining ring R-32
Ball bearing
6201DDW
Bearing box
Turn Bearing box upside down.
Receive Bearing box on U groove of Arbor
press table as shown right, and press down
Flat washer 12 and Ball bearing 6201DDW
with 1R027
Flat washer 12/ Ball bearing 6201DDW
U groove of Arbor press table
1R027
Arbor press
Bearing box
Ring
spring 11
Gear housing
Bearing box
Ball bearing
696ZZ
M4x14 Pan head
screw (4 pcs.)

ASSEMBLING
Repair
P 7/ 14
DISASSEMBLING
ASSEMBLING
Assemble by reversing the disassembly procedure.
Note: When Spindle is pressfit into Spiral bevel gear 37:
1. insert the thread of Spindle into the hole of 1R034 to
receive the stepped portion of Spindle on 1R034.
2. put 1R029 on the area around the center hole of
Spiral bevel gear 37 and then press it down.
See Fig. 20.
(1) According to Fig. 13 in the previous page, remove Bearing box from Motor housing.
(2) Disassemble Shaft lock section as drawn in Figs. 21 and 22.
Fig. 20
Fig. 21
[3] DISASSEMBLY/ASSEMBLY
[3]-2. Spiral bevel gear 37, Ball bearing 696ZZ and Ball bearing 6201DDW (cont.)
[3]-3. Shaft lock section
1R029
Bearing
box
Spiral bevel
gear 37
Spindle
1R034
Arbor press
Apply 1R268 to Shoulder pin 4 through the small hole
on Pin cap and tap 1R268 with a metal hammer.
Shoulder pin 4 is removed from Gear housing.
Release 1R268 from Pin cap carefully so that Pin cap is
not slung by Compression spring 8.
Shoulder pin 4
Gear housing
Note: Remove some plastic
dust on this area before
reassembling.
Pin cap
Note: Do not re-use removed Pin cap because removal one
damages the inside surface of the cap.
Compression
spring 8
O ring 5
Small hole on Pin cap
1R268
Fig. 22
Assemble by reversing the disassembly procedure.

Repair
P 8/ 14
Refer to Figs. 23 and 24.
Fig. 23
Fig. 24
[3] DISASSEMBLY/ASSEMBLY
[3]-4. Assembling of Stator complete
Fit four projections on Housing set into four the mating cavity in Stator complete.
Mating cavity on the left side and the right side (Two each)
Projection in Housing on the left side and the right side (Two each)
Stator complete
Be sure to align the center line of Bearing room with the terminal of Stator complete.
Terminal of Stator complete
Bearing room (to fit Ball
bearing 607LLB of Rotor
complete) on Housing set

Repair
P 9/ 14
Refer to the following and next pages. (Figs. 25, 26, 27, and 28)
Fig. 25 Fig. 26
Insert the hook of Switch knob into
the square hole of Switch lever
Protrude the bar of Lever from
the triangle hole of Switch lever.
Turn the bar of Lever counterclockwise to place
the long bar end and the short bar end onto
the depressions on the triangle corners of Switch lever.
[3] DISASSEMBLY/ASSEMBLY
[3]-5. Assembling of Switch knob and Switch lever
Switch lever Switch knob The ends of Torsion spring 2
must be placed on
these positions.
Fig. 27
Set Torsion spring 2 in place of Lever, and then
pass Pin 2 through the holes of Lever.
Lever
Pin 2
Torsion spring 2
Upper view
Long bar end of Lever
The curve of Lever must be faced
toward the center of the triangle hole.
Long bar end of Lever
Depressions on the triangle
corners of Switch lever
Short bar end of Lever

Repair
P 10/ 14
[3] DISASSEMBLY/ASSEMBLY
[3]-5. Assembling of Switch knob and Switch lever (cont.)
Fig. 28
Insert one end of Pin 2 into the hole of Housing L.
and put the one end of Torsion spring 2 on the rib
of Housing L. (See below for the detail.)
The other end of Pin 2 should be inserted into
the hole of Housing R.
Place the top projection on the reverse side of Switch knob
into the groove of Housing L. (See below for the detail.)
Inside view of Housing L (before assembling)
Groove
RibHole
Inside view of Housing L (after assembling)

P 11/ 14
Circuit diagram
Fig. D-1
Lead wire
(red, #14*)
AWG*: American wire gauge
Insulated terminal
(for M3.5 Pan head screw)
Lead wire
(white, 14AWG*)
Lead wire
(orange, 22AWG*)
Polyolefin
tube
Flag terminal with lock
(#250, t=0.8mm)
Flag terminal with lock
(#187, t=0.8mm)
Battery terminal
Line filter (if used)
Resistor unit
Connector 2-SD
Lead wire
(red, 14AWG*)
Lead wire
(yellow, 22AWG*)
Lead wire
(black, 14AWG*)
Lead wire
(red, 18AWG*)
Lead wire
(red, 20AWG*)
Lead wire
(white,
20AWG*)
Lead wire
(red, 22AWG*)
Lead wire
(white,
14AWG*)
Tape
Controller
• The orange lead wire end from Controller can be connected to either or .
The one white lead wire end must be connected to either or together with
the orange lead wire end, and then the other white lead wire end must be connected
solely to the opposite terminal. Use Insulated terminals and M3.5 Pan head screws
as drawn above.
1 2
1 2
Plastic tie
Stator
Lead wire (orange, 14AWG*)
Lead wire (white, 14AWG*)
Lead wire (blue, 14AWG*)
Lead wire
(red, 28AWG*)
Lead wire
(white, 28AWG*)
Lead wire
(blue, 28AWG*)
Lead wire
(black, 28AWG*)
Lead wire
(green, 28AWG*)
Lead wire
(yellow, 28AWG*)
Straight terminal without lock
(#110, t=0.8mm)
Straight terminal with lock
(#187, t=0.8mm)
Circuit diagram of Switch
2
1
2
1

Wiring diagram
P 12/ 14
Fig. D-2
Switch
Controller
Connect Lead wire (white) and Lead wire (orange) to
Switch with Insulated terminal.
Be careful about the directions of the insulated terminals.
Insulated terminals
Battery
terminal Stator completeRib B
Rib D
Rib F
Projection on
Flag terminal
Rib E
Rib C Connector 2-SD
Resistor unit
Line
filter
Rib A
When Line filter is used, insert it
between Rib E and Rib F.
Important:
Three Flag teminals and two straight teminals (circled by red)
have a lock structure, that enables you to remove the flag/ straight
terminals from the tab of Battery terminal with ease.
While pushing the projection of the flag/ straight teminal with
a slotted screwdriver to release the lock, pry off the flag/ straight
terminal from the tab of Battery terminal as shown left.
Note: Check whether flag/ straight terminals have a lock structure
before disassembly as follows:
• Find the projection on flag/ straight terminals.
• Swing flag/ straight terminals slightly and gently to
feel a little backlash due to the lock structure.
Never force to pull any flag/ straight terminals !
Connect flag/ straight terminals onto the tabs of Battery terminals
until you can hear a tiny click sound.
Lead wires from Terminal must be
routed between Rib C and Rib D.
Thick Lead wire from Stator complete must be bent
to prevent pinching between Housing L and R.
Lead wires covered with a tube from Stator complete
must be placed under Thick lead wire.
Lead wires covered with a tube from Stator complete
must be routed between Rib A and Rib B.
Do not put any
Lead wires on
this boss.
Place Resistor unit and Connector 2-SD in the area
circled by a blue broken line. Connector 2-SD must
not be placed on/ under Noise suppressor (if used).
Be sure to use
Resistor unit.
Lead wire (white)
between Terminal 1
and Terminal 2
Lead wire (orange) from Controller
Battery terminal
Slotted screwdriver

P 13/ 14
Trouble shooting
Whenever you find any trouble in your machine, first, refer to this list to check the machine for solution.
(1) Use the full charged battery which has the star mark. (Fig. D-3)
(2) Check the functions by repeating 10 times.
(3) When Housing is disassembled, check the following conditions:
mechanical trouble (lock or wrong setting etc.) poor connection of Connectors,
Terminals and screws, lead wire breakage and pinching, wrong contact between
Battery and Terminal
Note in Repairing
Check List for Trouble Shooting (Fig. D-4)
Motor runs when the machine
is switched on.
Try 10 times. In case of running
inconstantly, go to “No”.
Mode lamp is on.
All 3 stages of Battery power
remaining lamp are on.
1 or 2 stages of Battery power remaining lamp
is/are on.
Symptom Cause Corrective action
Unusal behavior occurs during work./
Rotor is rubbed Stator complete.
Controller is broken. Replace Stator complete.
Mechanical problem happens. Identify the mechanical
problem and repair or
replace the part(s).
Locate the incomplete
connection and repair
or replace them.
Controller is broken. Replace Stator complete.
Switch is broken.
Yes
No
Yes
No
Yes
No
No
No
The machine does not have any trouble.
Yes
Yes
Yes
Controller is broken. Replace Stator complete.
No
Controller is broken. Replace Stator complete.
Roter is broken. Replace Rotor
Stator complete is broken. Replace Stator complete.
Controller is broken. Replace Stator complete.
Connectors are in incomplete
connection. Connect them firmly.
Lead wires are broken.
Locate the incomplete
connection and repair
or replace them.
Connectors are in incomplete
connection. Connect them firmly.
Lead wires are broken.
Check the items from the top of the following list. (Descriptions of the items are referred to Circuit diagram in Fig. D-1.)
Replace Switch.
Replace the parts whose
terminals are broken.
Terminals are broken.
Star mark
Fig. D-3
Fig. D-4
When you test with Digital tester (1R402),
the proper value is obtained.
(Refer to the next page.)
In case the tester is not ready, go to “Yes”
Mode lamp

Fig. D-5
Test for recognizing the trouble on Stator complete
(1) Set Digital tester (1R402) in the diode mode ( mark on the tester: Refer to Fig. D-5.)
(2) Remove Battery, and then turn on Switch. (Fig. D-6)
(3) Attach Black tester bar to Plus terminal of Battery terminal.
Attach Red tester bar to Minus terminal of Battery terminal. (Fig. D-7.)
Note: Be careful not to revere them. The reverse attachment could spoil the test.
(4) Wait until the Tester shows the value without fluctuation. There is no fault on Stator complete if the tester indicates
within 0.8V plus/minus 0.1V.
If Tester indicates 0V or 0.4V approximately, Stator complete is out of order.
Replace Stator complete with new one.
P 14/ 14
Trouble shooting
Fig. D-6
Switch knob: lock-on position
Fig. D-6
Battery terminal