Makita GA7020R Manual

Model No.
Description
CONCEPT AND MAIN APPLICATIONS
P 1/ 9
Standard equipment
Optional accessories
Note: The standard equipment for the tool shown above may vary by country.
GA7020R/ GA9020R
Models GA7020R/ GA9020R are developed as sister tools of
GA7020S/ GA9020S.
Additionally to the benefits of models GA7020S/ GA9020S,
GA7020R/ GA9020R feature:
- Anti-restart function
- Large trigger switch with a lock lever having two different
actions for releasing the switch from Lock-off position and
locking the switch on in order to comply with the requirement
of the new IEC Regulations
Wheel size is:
180mm (7'') for Model GA7020R
230mm (9'') for Model GA9020R
Lock nut wrench 35 ......... 1 pc
Side grip 36 ...................... 1 pc
Dimensions: mm (")
Width (W)
Height (H)
Length (L)
Model No. GA7020R GA9020R
473 (18-5/8)
200 (7-7/8) 250 (9-7/8)
140 (5-1/2)
Vibration absorbing side grip
Toolless quick adjustable wheel cover
Toolless lock nut
Dust cover attachment
Plastic carrying case
GA7020R: Accessories for 180mm angle grinder
GA9020R: Accessories for 230mm angle grinder
Specification
Continuous Rating (W)
Cycle (Hz) Input Output Max. Output (W)
50/ 60
50/ 60
50/ 60
50/ 60
50/ 60
1,650
---
2,200
2,200
2,200
1,100
1,100
1,400
1,400
1,400
2,750
2,750
3,300
3,300
3,300
Voltage (V)
110
120
220
230
240
15
15
10.5
10
9.6
Current (A)
Angle Grinders 180mm (7'')/ 230mm (9'')
PRODUCT
TECHNICAL INFORMATION
Net weight*3: kg (lbs)
Power supply cord: m (ft)
GA7020R GA9020R
6,6008,500
Yes
Yes
Yes
180 (7)
22.23 (7/8)
230 (9)
2.0 (6.6)*1/ 2.5 (8.2)*2
5.6 (12.4) 5.8 (12.8)
Specification
Soft start feature
Anti-restart function
Double insulation
No load speed: min-1= rpm.
Wheel size: mm (") Diameter
Model No.
Hole diameter
*1 for Brazil, Australia
*2 for all countries except the two listed above
*3 Weight according to EPTA-Procedure 01/2003, with Side grip, Wheel cover, Inner flange, Lock nut
L
H
W

P 2/ 9
Repair
[1] NECESSARY REPAIRING TOOLS
[2] LUBRICATIONS
Fig. 1
Code No. Description Use for
1R004 Retaining ring pliers ST-2 Removing Retaining ring 15 from Spindle ass’y
1R252 Round bar for arbor 30-100 Assembling Felt ring 18 to Gear housing complete
1R269 Bearing extractor Assembling / disassembling Ball bearings
1R005 Retaining ring pliers RT-2N Removing Retaining ring R-42 from Gear housing complete
Assembling large Spiral bevel gear to Spindle ass’y
1R165 Ring spring setting tool B
Item No.
Apply the following lubricant to protect parts and product from unusual abrasion.
Description Portion to lubricate AmountLubricant
5Gear housing complete Gear room
5
not grooved
grooved
CAUTION: Repair the machine in accordance with “Instruction manual” or “Safety instructions”.
60g
Makita grease SG No.0
[3] DIFFERENCE BETWEEN GA7020R AND GA9020R
Item No. Parts of GA7020R
Spiral bevel gear 16 Spiral bevel gear 12
Parts of GA9020R
7
38
In addition to Wheel cover and available Wheels, the following parts are different.
Spiral bevel gear 53B Spiral bevel gear 53A
Small spiral bevel gear
Description in Technical information
Large spiral bevel gear

P 3/ 9
Repair
[4] DISASSEMBLY/ASSEMBLY
[4]-1. Armature, Small spiral bevel gear, Ball bearing 6301DDW
DISASSEMBLING
5x35 Tapping screw (4pcs.)
(1) Disassemble Armature and Small spiral bevel gear as illustrated in Figs. 2 and 3.
(2) Disassemble Ball bearing 6301DDW as illustrated in Figs. 4 and 5.
M6x22 Hex socket head bolt
(4pcs.)
Brush holder cap
Carbon brush
Armature
Turn Armature counterclockwise while
holding M8 Hex nut with Wrench 13.
M8 Hex nut can be removed.
Remove Carbon brushes. And then
remove 5x35 Tapping screws.
Remove Gear housing complete
together with Armature.
Remove Bearing box and M6x22
Hex socket head bolts.
Wrench 13 for locking M8 Hex nut
M8 Hex nut
Pull off Armature while
holding Small spiral bevel gear.
Small spiral
bevel gear
Armature
Fig. 2
Fig. 3
Remove Retaining ring R-42 with 1R005,
then remove Flat washer 20.
Fig. 4 Fig. 5
Retaining ring
R-42
Flat washer 20
Ball bearing 6301DDW
M8 Hex nut Small spiral bevel gear
Ball bearing 6301DDW
Felt ring 18 (a component of Gear housing complete)
Rubber ring 38
Gear housing complete
Set Armature and Small spiral bevel gear to Gear housing complete.
And set M8 hex nut in place temporarily by reversing the step of
Fig. 3.
Tap the end of Gear housing complete with a plastic hammer.
Ball bearing 6301DDW can be removed from Rubber ring 38 in
Gear housing complete. Felt ring 18 falls off at that time.
Gear housing complete
Note: If the above work is very difficult
due to the seizing of Small spiral
bevel gear, spray a lubricant
between Armature shaft and Small
spiral bevel gear. And then turn
and pull Armature while holding
Small spiral bevel gear with pliers
and a cloth.

P 4/ 9
Repair
[4] DISASSEMBLY/ASSEMBLY
[4]-1. Armature, Small spiral bevel gear, Ball bearing 6301DDW (cont.)
DISASSEMBLING
ASSEMBLING
(3) Disassemble Armature as illustrated in Fig. 6.
Assemble Gear housing section by setting Felt ring 18, Ball bearing 6301DDW, Flat washer 20 and Retaining ring R-42
in place of Gear housing complete.
(1) Set Felt ring 18 in place as illustrated in Fig. 7 when disassembling Ball bearing 6301DDW.
Remove M8 Hex nut and small Spiral bevel gear again.
Ball bearing 6301DDW can be removed by hand.
Remove Ball bearing 6200DDW with 1R269.
Fig. 6
Fig. 7
M8 Hex nut
1R269
Ball bearing 6301DDW Ball bearing 6200DDW Small spiral bevel gear
Felt ring 18
V-block
Felt top portion
Steel cup portion
1R252
Cross-section of the bottom
of the bearing room
1R252 Rubber ring 38
Felt ring 18
Flat washer
0.5mm
Put a Flat washer (illustrated above) temporarily on Felt ring 18.
Then press down the Flat washer with arbor press and 1R252
carefully to move the Flat washer to only 0.5mm downwards.
Remove the Flat washer after setting Felt ring 18 in place.
Bottom step in Gear housing complete
28mm in outer
diameter
0.5mm in
thickness
Flat washer as a jig
Hold Gear housing complete with two
V-blocks, and pressfit Felt ring 18 into
the hole of Gear housing complete so that
the felt top portion and the bottom step of
Gear housing complete is in line.

P 5/ 9
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-1. Armature, Small spiral bevel gear, Ball bearing 6301DDW (cont.)
ASSEMBLING
(2) Assemble Ball bearing 6301DDW to Gear housing complete as illustrated in Fig. 8.
(3) Assemble Armature and small Spiral bevel gear to Gear housing complete as illustrated in Fig. 9.
Fig. 8
Armature with Ball
bearing 6301DDW Armature
Assemble Ball bearing 6301DDW to
Armature temporarily.
After setting Ball bearing 6301DDW in
place of Gear housing complete, pull off
Armature.
Retaining
ring (INT) R-42
Flat washer 20
Make sure that Rubber
ring 38 is set in place.
(Refer to Fig. 7)
Putting Flat washer 20 on Ball
bearing 6301DDW, secure them
with Retaining ring (INT) R-42.
Rubber ring 38
1R005
Small spiral
bevel gear M8
Hex nut
Armature
Ball bearing
6301DDW
Insert Armature shaft through Small spiral bevel gear
and Ball bearing 6301DDW in Gear housing.
Set M8 Hex nut to
Armature shaft.
Holding M8 Hex nut with Wrench 13,
turn Armature clockwise by hand firmly.
Fig. 9
(4) Assemble Gear housing complete to Motor housing, And assemble Bearing box section to Gear housing complete.
Reverse the disassembling step in Fig. 2.
Ball bearing
6301DDW

P 6/ 9
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-2. Large spiral bevel gear, Ball bearing 6203DDW, Ball bearing 6000LLB
DISASSEMBLING
1R269
Remove Bearing box from Gear
housing complete.
Remove Ball bearing 6000LLB
with 1R269.
Remove Spindle ass’y by pressing with Arbor press.
Ball bearing 6203DDW in Bearing box has a damage in this step.
Do not reuse Ball bearing 6203DDW after removal of Spindle ass’y.
Ball bearing
6000LLB
M6x22 Hex socket
head bolt (4pcs.) Ring spring 11
1R004
Spindle ass’y
Bearing box
Turn table of Arbor press Turn Table of Arbor Press
Bearing
retainer 50
Slotted screwdriver
Enlarging the clearance of Ring spring 11
with 1R004, lift up the opposite side
with slotted screwdriver.
Ring spring 11 can be removed.
Fig. 10
Fig. 11R
Correct setting The following wrong settings causes deforming.
Fig. 11F
Fig. 12
Large spiral bevel gear
Bearing box
M5x16 Pan head
screw (3pcs.)
Remove Bearing retainer 50 by
unscrewing three M5x16 Pan
head screw.
(1) Large spiral bevel gear can be disassembled as illustrated in Figs. 10, 11R and 12.
Ball bearing
6203DDW
The brim portion of Bearing
box is received with Turn table
of arbor press.
Labyrinth ring portion of Spindle
ass’y is received with Turn table
of arbor press.
Receive the cylindrical portion
of Bearing box with Turn table
of arbor press.
Cylindrical portion

1R165
Large spiral bevel gear
P 7/ 9
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-2. Large spiral bevel gear, Ball bearing 6203DDW, Ball bearing 6000LLB (cont.)
DISASSEMBLING
ASSEMBLING
Assemble new Ball
bearing 6203DDW.
Assemble Bearing
retainer.
Assemble Spindle ass’y.
Receive not only the brim portion
but also the cylindrical portion of
Bearing box with Turn table of Arbor
press when assembling Spindle ass’y.
(2) Ball bearing 6203DDW can be disassembled as illustrated in Fig. 13A, or Fig. 13B.
(1) Assemble Ball bearing 6203DDW and Spindle as illustrated in Fig. 14.
(2) Assemble large spiral bevel gear to Spindle as illustrated in Fig.15.
Bearing
retainer 50
M5x16 Pan head
screw (3pcs.)
Fig. 13A Fig. 13B
Fig. 14
If it is difficult to remove as illustrated
in Fig. 13A, remove Ball bearing
6203DDW with the appropriate
diameter round bar and Arbor press.
Remove Ball bearing 6203DDW by striking Bearing box
against Work table.
Ball bearing
6203DDW
Bearing box
Round bar
Ball bearing 6203DDW
Brim
Cylindrical portion of
Bearing box
Spindle
ass’y
Putting Large spiral bevel gear on 1R165, press Spindle into
Arbor hole of Large spiral bevel gear with Arbor press.
Fig.15
(3) Assemble Ring spring 11 and Ball bearing 6000LLB. (Fig. 10)

P 8/ 9
Repair
[3] DISASSEMBLY/ASSEMBLY
[3]-3. Shaft lock mechanism
DISASSEMBLING
Fig. 16
Fig. 18 Fig. 19
ASSEMBLING
(1) Remove Gear housing complete from Motor housing.
Remove Bearing box from Gear housing complete as illustrated in Fig. 2.
(2) Remove Armature from Gear housing complete as illustrated in Fig. 3.
(3) Shaft lock mechanism can be disassembled as illustrated in Figs. 16 and 17.
Applying 1R268 to Shoulder pin 5 through the small hole
on Pin cap, tap 1R268 with Plastic hammer.
Shoulder pin 5 comes out from Gear housing complete.
Release 1R268 from Pin cap while paying
attention that Pin cap would not be slung
by Compression spring 12.
Shoulder pin 5
Pin cap
Note: Do not reuse Pin cap, Removal of
Shoulder pin 5 damages the inside surface
of Pin cap, producing plastic dust.
Pin cap
Compression
spring 12
Pin cap
Compression
spring 12
Fig. 17
(1) Be sure to use a new Pin cap for replacement and to remove all the plastic dust on Shoulder pin 5. (Fig. 18)
(2) Assemble the parts for Shaft lock mechanism as illustrated in Fig. 19.
Plastic dust
O ring 9
Shoulder pin 5
Shoulder pin 5
Make sure that O ring 9 is
mounted to Shoulder pin 5
illustrated below.
Assemble Compression spring 12
and Pin cap by pressing them to
Shoulder pin 5.
Insert Shoulder pin 5
through the hole of Gear
housing complete.
1R268

Circuit diagram
Wiring diagram
P 9/ 9
Fig. D-1
Power supply cord Switch Noise
suppressor
Controller
Makita
logo side
Brown lead wire is used
for some countries.
Fig. D-2
Blue lead wire is used for some countries.
Blue lead wire is used
for some countries.
Makita
logo side
Pass Field lead wires (black, white)
by this Hook.
Guide out Field lead wire
(white) by this Hook.
Guide out Field lead wire
(black) by this Hook.
Belly side
(Name plate side)
Belly side (Name plate side)
Back side
(Bumper side)
White
Color index of lead wires' sheath
Black Red
Motor housing
viewed from
Commutator side
Fix Field lead wire (white)
with these Lead wire holders.
Fix Field lead wires (black, white) with this Lead wire holder.
Wiring in Motor housing
on Commutator side
Fig. D-3
Noise suppressor
Power supply cord
Lead wires of
Power supply cord
Put Lead wires of power supply
cord between Switch and Rib.
Controller
Switch
Rib
Rib
Sponge sheet
Pass Controller’s Lead wires (black, red) through Sponge sheet.
Pass Controller’s Lead wires
(white, red) by the Rib.
Do not pinch Controller’s lead wires (white, red)
between Switch and inner wall of Handle set.
Wiring in Handle complete (L)