Makita HR4501C Manual

Model No.
Description
NEW TOOL
CONCEPT AND MAIN APPLICATIONS
P 1/ 23
Specification
Standard equipment
Optional accessories
Side handle (D-shaped) .............. 1
Side handle (Bar-shaped) ........... 1
Depth gauge ............................... 1
TCT bits, Core bits, Bull points, Cold chisels, Scaling chisels,
Scaling chisel (for Tile), Grooving chisel, Clay spade, Bushing tool, Rammer,
Shank (for Bushing tool and Rammer), Chemical anchor adapter, Bit grease
Hammer grease, Side handle (D-shaped), Plastic carrying case, Blow-out bulb,
Safety goggle, Hammer service kit
Bit grease ................................. 1
Plastic carrying case ................ 1
Cleaning cloth .......................... 1
Dimensions: mm (")
Width (W)
Height (H)
Length (L)
Model No. HR4501C HR4510C HR4511C
458 (18)
136 (5-3/8)121 (4-3/4)
288 (11-3/8)
Note: The standard equipment for the tool shown above may differ by country.
HR4501C, HR4510C, HR4511C
Rotary Hammers 45mm (1-3/4")
HR4501C series models have been developed as successor models
of HR4500C, featuring low vibration level and high work efficiency.
Listed below are their main features.
Active dynamic vibration absorber
Model No.
Vibration absorbing handle
Selectable two on-off switches
HR4501C
Yes Yes
Yes
YesYes
No
No
HR4510C HR4511C
No
No
HR4501C
L
H
W
HR4511C
HR4510C
No load speed: min-1=rpm
Impacts per min: min-1=ipm
Model No. HR4501C HR4510C
8.4 (18.5) 8.5 (18.7)7.8 (17.2)
Europe: 4.0 (13.1), Other countries: 5.0 (16.4)
HR4511C
Shank type
Capacities: mm (")
Torque limiter
Double insulation
Net weight: kg (lbs)
Power supply cord: m (ft)
Electronic
features
Variable speed control by dial
Constant speed control
Soft start
Yes
Yes
Yes
Yes
Yes
45 (1-3/4)
125 (5)
130 - 280
1,250 - 2,750
Max Core bit diameter
Max TCT bit diameter
SDS-Max
TECHNICAL INFORMATION
120
110
220
230
240
14 1,350
---
600 1,60050/60
7 1,350 600 1,70050/60
7 1,350 600 1,70050/60
7 1,350 600 1,70050/60
13.5 600 1,60050/60
Continuous Rating (W)
Voltage (V) Cycle (Hz) Input Output Max. Output (W)
Current (A)

P 2/23
[2] LUBRICATION
[1] NECESSARY REPAIRING TOOLS
CAUTION: Unplug the tool and remove the bit for safety before repair/ maintenance
in accordance with the instruction manual!
Fig. 1
Barrel and Tool holder section
Repair
DescriptionCode No. Use for
Item No. Description Grease AmountPortion to lubricate
1R003 Retaining ring S Pliers ST-2N
1R040 Armature holder 50 set for Vise
1R045 Gear extractor (large)
Tip for Retaining ring pliers1R212
1R213 Cylinder extractor
1R214 Taper sleeve
1R228 1/4” Hex. shank bit for M4
1R230 1/4” Hex. shank bit for M6
1R269 Bearing extractor
1R291 Retaining ring S and R Pliers
1R346 Center attachment
1R350 Ring 60
Removing / Mounting Ring spring
Supporting 1R213 when removing Cylinder
Removing Armature from Gear housing complete
Attachment for 1R003
Disassembling Cylinder from Crank housing
Fitting Fluoride ring 28 to Impact bolt
Screwing / Unscrewing M4x25 Hex socket head bolt of Barrel cover
Screwing / Unscrewing M6x30 Hex socket head bolt of Barrel
Removing Ball bearings
Removing / Mounting Retaining rings
Attachment for 1R045
Supporting 1R213 when removing Cylinder
23
25
9
9
22
18
16
(16b)
1
(16c)
(16a)
20
21
1
16
18
20
22
25
23
Tool holder cap
9 Tool retainer
(16a) Oil seal 35
(16b) Plane bearing 36
Barrel
complete
(16c) Plane bearing 48
Flat washer 36
Flat washer 36
Bit installation side
Crank housing side
21 Tool holder 15g
a little
a little
Inner surface where 25 Impact bolt contacts
X ring 21
Impact bolt
Fluoride ring 28
Lip portion
Portion where Bit contacts
Inner surface where 21 Tool holder contacts
Portion where 21 Tool holder contacts
Drum portion
N No.2
R No.00
Apply the following lubricants to protect parts and product from unusual abrasion:
*Makita grease N No. 2 (Part No. 181573-3: Grease vessel 93g) with white triangle
*Makita grease R. No.00 (Part No. 181490-7: Hammer grease 30g) with black triangle

P 3/ 23
[2] LUBRICATION (cont.)
Repair
Item No. Description Portion to lubricate Amount
Apply Makita grease R. No.00 and N.No.2 to the following portions designated with the black triangle to protect
parts and product from unusual abrasion.
82 Crank housing complete
40 Cylinder 34
37
48
39
49 O Ring 27 on Piston
Straight bevel gear 35
Connecting rod
O Ring 27 on Striker
99 Gear housing complete
Oil seal 15
Inside between Striker and Piston
Whole portion
Gear teeth
Hole for Crank shaft pin
Whole portion
Gear teeth of Torque limiter, Spur gear 19,
Helical gear 36 and Armature
Crank room
Lip portion
Inner periphery of Plane bearing 59
(The component of Crank housing completete)
Fig. 2
Grease
R No.00
82
Crank shaft
40
37
49
48
39
99
146 Armature
Torque limiter
assembly
82a 82b
82b
82a
146
Striker
Piston
Crank housing and Motor section
25g
25g
a little
a little
5g
a little
Fig. 3
Item No. Description Portion to lubricate Amount
O Ring 8
O Ring 12
O Ring 22
Drum portion where Pipe 20 contacts
Whole portion
AVT mechanism (for HR4510C and HR4511C only)
Pipe 20
Spring guide
Counter weight
Compression spring 14
Pipe holder
58
58
55
52
50
61
63
57
57
Grease
R No.00 a little
55
61
52
63
50

P 4/ 23
[3] DISASSEMBLY/ASSEMBLY
[3] -1. Chuck Section
Repair
DISASSEMBLY
4x14 Tapping
Screw (2 pcs.)
Handle section
1) Disassemble Handle section. (Fig. 4) Hold the machine upright and disassemble Chuck section in the order of Figs. 5
to 11.
Connector
Controller
Motor
housing
Tool holder cap
Holding the machine upright with
1R350 as illustrated below, remove
Tool holder cap.
1R350
1. Separate Handle section from Motor housing
by unscrewing 5x25 Tapping screws.
2. Pull off Connector from Controller.
3. After removing 4x14 tapping screws, disassemble
Controller from Motor housing.
Ring spring 25
While pulling down Chuck cover, remove Ring spring 25
from the Tool holder using 1R003 with 1R212.
1R003 with 1R212
Chuck cover
1R003
Fig. 4 Fig. 5
Fig. 6 Fig. 7
Tool holder
Tool holder
Ring 28
Ring 28
After removing Ring spring 25, disassemble
the following parts in order from Tool holder.
1. Ring 28
2. Chuck cover
3. Spacer
Ring spring 25
Chuck cover
Spacer
Chuck ring
5x25 Tapping
screw (6 pcs.)

P 5/ 23
[3] DISASSEMBLY/ASSEMBLY
[3] -1. Chuck Section (cont.)
Repair
DISASSEMBLY
ASSEMBLY
Fig. 8
Fig. 10
Fig. 9
Fig. 11
Tool holder
Do the reverse of the disassembling steps. Refer to Figs. 11 to 4.
Note: If it is difficult to mount Tool holder cap by hand, press the
machine onto Tool holder cap after assembling Handle section.
(Fig. 12)
Reserve the space for Tool retainer removing
by pressing down Spring guide. And take off
Tool retainers (2pcs.) from Tool holder.
Disassemble Spring guide and Compression
spring 49 from Tool holder.
Ring spring 25
Remove another Ring spring 25 from
Tool holder.
Remove Chuck ring and Release cover.
Chuck ring
Tool holder
Tool retainer
Release cover
Release cover
Chuck ring
Tool holder Tool holder
Tool
retainer
Tool retainer Spring guide
Spring guide
Tool holder cap
Compression
spring 49
Fig. 12
Spring guide

P 6/ 23
[3] DISASSEMBLY/ASSEMBLY
[3] -2. Tool Holder Section
Repair
DISASSEMBLY
1) Disassemble Chuck section. (Figs. 4 - 11)
2) Disassemble the Tool holder section in the order of Figs. 13 -17.
M4x25 Hex socket head bolt
Unscrew M4x25 Hex socket head bolt
and remove Barrel cover complete.
Remove Impact bolt from
Tool holder.
Disassemble Barrel complete
together with Tool holder by
unscrewing M6x30 Hex
socket head bolts (4 pcs.).
Separate Tool holder from Barrel
complete. Then remove Flat washer
36 (2pcs.) and Urethane ring 36
from Tool holder.
M6x30 Hex socket
head bolt (4 pcs.)
Barrel cover complete
Barrel complete Barrel complete
Barrel complete Flat washer 36
Flat washer 36
Urethane
ring 36
Tool holder
Tool holder
Tool holder
X ring 21
All the Rings on Impact bolt have to
be replaced if O ring 23 (orange)
can be seen through the worn Fluoride
ring 28.
O ring 23
Fluoride ring 28
(the worn one)
Fig. 13 Fig. 14 Fig. 15
Fig. 16 Fig. 17
Ring 19
Rubber ring 20
Remove the following parts from
Crank housing.
These parts may come out with Barrel
complete in the step of Fig. 14.
In this Case, they are disassembled
from Tool holder in the step of Fig. 16.
Ring 38
Shoulder sleeve 19
Slide sleeve
Impact bolt
Impact bolt

P 7/ 23
[3] DISASSEMBLY/ASSEMBLY
[3] -2. Tool Holder Section (cont.)
Repair
DISASSEMBLY
ASSEMBLY
Ring 38
O ring 53 and Lock sleeve are
removed from Driving sleeve.
Driving sleeve section
Striker Cylinder 34
Straight bevel gear 35
Compression
spring 39
Link arm
O ring 27
Replace the old O ring 27
in this step.
O ring 53
Lock sleeve
Lock sleeve
Driving sleeve
Fig. 18
3) Parts assembled to Cylinder 34 are removed. (Fig. 18)
1) Pay attention to the descriptions in Figs. 19 and 20.
2) Insert Striker into Cylinder 34. And to Crank housing, assemble Straight bevel gear 35, the Driving sleeve section
with Link arm, Compression spring 39 and Ring 38. Refer to Fig. 18.
Fig. 19
Fig. 20
O ring 27
Bulge portion
Crank housing sideImpact bolt side
Rib on Link arm
Mount Lock sleeve
on Driving sleeve.
Fit O ring 53 into the
grooves on Driving
sleeve.
Fit the rib of Link arm into the groove
on Driving sleeve.
Facing O ring 27 installation side of Striker to Crank housing, insert Striker into Cylinder 34.
Groove on Driving sleeve
Straight bevel gear 35
(assembled in Crank
housing complete)
Grooves for O ring 53
O ring 53
Driving sleeve
Fix Driving sleeve to Crank housing
while engaging with Straight bevel gear 35.
Driving sleeve

P 8/ 23
[3] DISASSEMBLY/ASSEMBLY
[3] -2. Tool Holder Section (cont.)
Repair
ASSEMBLY
1R214
Correction
Insert Impact bolt from
the HR5001C side of
1R214 and keep it aprox.
60 seconds.
Impact bolt
Assembly of Rings to Impact Bolt
Assembly of Impact Bolt Section
Fig. 21
Fig. 22 Fig. 23
Before correction:
Rings' edges are protruding from
the top edge of the groove on
Impact bolt.
Groove on Impact bolt
Impact bolt Ring 19 Slide sleeve Flat washer 36
O ring 71
Barrel complete
Do not forget to mount O Ring 71
to Barrel complete.
Flat washers 36 (2 pcs.)
have to be assembled
to the both side of
Urethane washer 36.
Urethane washer 36
Rubber
ring 20
Shoulder
sleeve 19
Face the chamfered
edge to Impact bolt.
Face the conical side
to Slide sleeve.
Face the chamfered Side
to Shoulder sleeve 19.
Insert the assembled Impact
bolt section into Tool holder.
Fluoride ring 28
X ring 21 O ring 23
After correction:
Rings' edges are positioned
under the top edge of the
groove on Impact bolt.
Corrected
3) After installing Fluoride ring 28 on the groove of Impact bolt, the Ring is stretched and its edges are protruding from
the groove. Correct the deformation as illustrated in Fig. 21.
4) Assemble Impact bolt section, and insert it into Tool holder. (Fig. 22)
5) Assemble Tool holder and Rings to Barrel complete. (Fig. 23)
6) Take the reverse step of Disassembly to do the further steps.
Tool holder

P 9/ 23
[3] DISASSEMBLY/ASSEMBLY
[3] -3. Barrel Complete
Repair
DISASSEMBLY
ASSEMBLY
1) Remove Barrel complete from the machine as illustrated in Figs. 13, 14 and 15.
2) Remove Ring spring 50 and Oil seal 35 as illustrated in Figs. 24 and 25.
Ring spring 50
Oil seal 35
Oil seal 35
Lip portion
Barrel complete
Note: Facing the lip portion of Oil seal 35 to Tool holder cap side,
fit Oil seal into Barrel complete.
1) Fit Oil seal 35 into Barrel complete. Refer to Fig. 26.
2) Secure Oil seal with Ring spring 50. Refer to Fig. 24.
With thin slotted screwdriver,
remove Ring spring 50 for securing
Oil seal 35 in Barrel complete.
Oil seal 35
Push out Oil seal 35 by striking with slotted
screwdriver.
Fig . 24 Fig. 25
Fig. 26
Tool holder
cap Side

P 10/ 23
[3] DISASSEMBLY/ASSEMBLY
[3] -4. Active Dynamic Vibration Absorber (HR4510C and HR4511C only)
Repair
DISASSEMBLY
1) Disassemble Chuck section. (Figs. 4 to 11) and remove Barrel cover complete and Barrel section. (Figs. 13 and 14)
2) Disassemble Active dynamic vibration absorber in the order of Figs. 27 to 30.
Fig. 27
Fig. 28 Fig. 29
Compression
spring 11
Spring guide
Absorber holder of
Crank housing complete
phillips
screwdriver
slotted screwdriver
Pipe holder
Push Spring guide
(inner part of the
Absorber).
Absorber holder
Spring guide will tilt to be
locked inside Absorber, and
this end of the Absorber is
released from Crank housing
complete
Disassemble Active dynamic vibration absorber as follows.
Disassemble Active dynamic
vibration absorber, by levering up
with two slotted screwdriver.
Active Dynamic
Vibration Absorber
Remove Crank housing
cover. Then set Change
lever to Rotation with
hammering mode.
Remove the Change
lever by unscrewing
4x14 Tapping screw.
Remove Crank cap cover
by unscrewing 4x14 Tapping
screw.
Then remove Control plate.
Remove Crank cap together
with Crank lever by unscrewing
M4x18 Pan head screw.
Crank housing cover
Change lever
Change lever
Crank cap cover
Control
plate
4x14 Tapping screw
4x14 Tapping screw (2 pcs.) M4x18 Pan head
screw (6 pcs.)
Crank cap
Crank lever
Pipe holder Pipe holder
O ring 8 O ring 12 O ring 8
O ring 12
O ring 22 O ring 22
Compression spring 11 Compression spring 11
Spring guide
Pipe 20
Counter weight Spring guide
Fig. 30
Pipe holders can be
separated by turning Pipe
holders while pushing
strong toward each other.

P 11/ 23
[3] DISASSEMBLY/ASSEMBLY
[3] -4. Active Dynamic Vibration Absorber (HR4510C and HR4511C only)
Repair
ASSEMBLY
DISASSEMBLY
Spring guide Spring guide
If Spring guide is
locked inside the
Absorber,
Push the locked
Spring guide to
protrude from Absorber.
Now Spring guide
protrudes.
Spring guide
Mount Active dynamic vibration absorber
while keeping its position parallel to
Crank housing.
Spring guide
Fig. 31 Fig. 32
Fig. 33
Fig. 34
1) Assemble Active dynamic vibration absorber. (Fig. 30)
2) Set Spring guide in place as illustrated in Fig. 31.
3) Mount Active dynamic vibration absorber on the both side of Crank housing complete. (Fig. 32)
4) Do the reverse step of disassembly in Fig. 27.
[3] -5. Crank Cap Section
1) Remove Crank cap section as illustrated in Fig. 27.
2) Disassemble Crank cap section as illustrated in Figs. 33 and 34.
Link plate
Crank cap
Crank cap
Link plate and Change lever
can be disassembled from
Crank cap.
M4x12 Pan head screw
(with threadlocker)
Crank lever
Torsion
spring 15
Pull off Torsion
spring 15 with
pliers.
Remove Link lever.
Link lever
Torsion spring 15
Link lever
Crank shaft
Crank lever
Link plate
While gripping Crank lever with water pump pliers, unscrew M4x12
Pan head screw using cordlress impact driver with philips bit.
phillips bit

P 12/ 23
[3] DISASSEMBLY/ASSEMBLY
[3] -5. Crank Cap Section
Repair
ASSEMBLY
Assemble Torsion spring 15 while hooking each tail to each wings of Link lever as follows.
2) Assemble Link plate to the Crank lever with M4x12 Pan head screw. Refer to Fig. 33.
Note: Apply adhesive (ThreeBond 1342 or Loctite 242) to the thread of M4x12 Pan head screw.
3) Slide Link plate fully to Handle installation side by hand so that Link lever's Pin portion can be moved within the frame
of Link plate after assembling Crank cap. (Fig. 36)
1) Assemble Link lever and Torsion spring 15 to Crank lever. (Fig. 35)
Link Lever
with Crank lever
Hook one tail of Torsion spring 15
to the lower wing edge of Link lever.
Hook the other tail to
the upper wing edge of
Link lever by pulling
with pliers.
Torsion spring 15
Link lever
Crank lever
Fig. 35
Slide Link plate fully to Handle installation side by hand.
If sliding Link plate by hand is impossible, Driving sleeve
does not engage with Straight bevel gear 35 when assembling
Tool holder section.
Push Driving sleeve to engaging it with Straight bevel gear 35
as illustrated in Fig. 20, and Link plate will come to the position
as shown in the center illustration in Fig. 36.
Link plate Link plate
Link lever's pin portion can be positioned
inside the frame of Link plate when Crank
cap section is assembled to Crank housing
complete.
Link plate can be slidden when Crank lever
turns.
Link
lever's Pin
Fig. 36
Crank lever
Keeping its position of Crank lever's protrusion as illustrated above,
assemble Crank cap section to Crank housing complete.
Crank lever
Note: Set Crank lever to
Rotation with
hammering mode.
Circle marker on Crank cap
4) Mode change mechanism has to be assembled in Rotation with hammering mode as illustrated in Fig. 37,
and Fig. 38 (for HR4511C) / 38A (for HR4501C and HR4510C) in the next page.
Crank housing complete
Protrusion
Fig. 37
Crank cap

P 13/ 23
[3] DISASSEMBLY/ASSEMBLY
[3] -5. Crank Cap Section
Repair
DISASSEMBLY
ASSEMBLY
1) Disassemble the Tool holder section in the order of Figs. 13 to 18. And disassemble Crank cap section as illustrated in
Fig. 27.
2) Disassemble the parts in Crank housing complete before removing Cylinder as illustrated in Figs. 39.
Link plate Guide
Remove Link plate
guide and Link plate.
Remove Ring spring 36
from the end of Cylinder 34
with small slotted
screwdriver.
Link plate
Crank housing Complete Ring spring 36
End of Cylinder 34
Ring 38
Fig. 39
5) After assembling Spring guide, mount Crank cap section. (Fig. 38: HR4511C only)
5A) Assemble Control plate by fitting its elliptic Loop portion with the protrusion of Crank lever.
Then mount Crank cap cover. (Fig. 38A: HR4501C and HR4510C only)
Change Lever
set in Rotation with hammering mode
Change Lever
set in Rotation with hammering mode
Crank cap
Control Plate
Control plate
Fig. 38: HR4511C only
Spring guide
Assemble Spring guide
at first.
Indication mark of
Rotation with hammering mode Indication mark of Rotation
with hammering mode
Crank cap cover
Crank cap cover
Note: Face the UP mark to Crank cap cover side
when assembling Control plate to Crank lever.
Fig. 38A: HR4501C and HR4510C only
Fig. 38B: HR4501C and HR4510C only
Assemble Control plate at first.
Refer to Fig. 38B.
[3] -6. Crank section, Cylinder, Piston
UP mark
Crank lever

P 14/ 23
[3] DISASSEMBLY/ASSEMBLY
[3] -6. Crank section, Cylinder, Piston (cont.)
Repair
DISASSEMBLY
4) Disassemble Piston in the order of Figs. 41 to 43.
Set Connecting rod to the
dead point on Cylinder
installation side by turning
Crank shaft.
Disconnect Connecting rod
from Crank shaft.
Pull out Connecting rod from Crank shaft.
Remove O ring 27
from Piston for
replacement.
Crank shaft
Ring 38 Ring 38
Piston
Ring 38
O ring 27
Connecting rod
Crank shaft Connecting rod Connecting rod
Piston
Fig. 41 Fig. 42 Fig. 43
Screwdriver
Wooden piece to protect the edge of Crank housing
complete
Cylinder 34
Cylinder 34 can be removed by levering
up with a pair of screwdriver.
Screwdriver
Fig. 40A
3A) Cylinder 34 can be disassembled without 1R213. Refer to Fig. 40A.
Ring 38 is left in Crank housing
complete after removal of Cylinder 34.
Fig. 40
1R350
1R0401R040
3) Disassemble Cylinder 34 as illustrated in Fig. 40.
1R350
1R213
Turn Handle clockwise. Cylinder 34 gripped with
1R213's claw is pulled out from Crank housing complete.
Set Repairing jigs as follows.

P 15/ 23
[3] -7. Switches, Controller, Power Supply Cord
Repair
DISASSEMBLY
5x25 Tapping
screw (6 pcs.)
4X18 Tapping screw
slotted screwdriver
Handle section
Handle cover
Handle
Main
switch
1) Main switch and Slide switch (for HR4501C and HR4510C only) can be disassembled as illustrated in Figs. 46 and 47.
4X14 Tapping
Screw (2 pcs.)
Handle
Connector
Disconnect Connector from Controller.
Unscrew 4x14 Tapping screw to remove Controller
in the next step.
Disassemble Handle section by
unscrewing 5x25 Tapping screws.
Main switch can be
replaced.
Disassemble Handle
cover by unscrewing
4x18 Tapping screw.
Controller
Fig. 46
Fig. 47 (HR4510C and HR4511C only)
Handle
Unscrew 4x14 Tapping screw and
separate Switch box from Handle.
Now Slide switch can be replaced.
Leaf spring
4x14 Tapping
screw
Slide switch Switch box
Slide lever complete Slide lever
complete
ASSEMBLY
1) Passing Connecting rod through Ring 38, connect Connecting rod to Crank shaft. Refer to Fig. 43.
2) Mount Ring spring 37 and O ring 35 (2 pcs.) on Cylinder 34 before assembling Cylinder 34 to Crank housing complete.
(Fig. 44)
3) Mount Ring 38 and Ring spring 36 to the Cylinder end which protrudes into Crank room.
Refer to Fig. 39 (right).
4) Regarding HR4510C and HR4511C, Seal plates have to be assembled to the position illustrated in Fig. 45.
5) Do the reverse step of disassembling.
O ring 35
Ring spring 37
Ring spring 37 functions
as a stopper to stop the
assembled Cylinder 34 at
the position as it was.
Fig. 44 Fig. 45 (HR4510C and HR4511C only)
Seal plate
[3] DISASSEMBLY/ASSEMBLY
[3] -6. Crank section, Cylinder, Piston

P 16/ 23
[3] -8. Motor Section
Repair
DISASSEMBLY
1) Disassemble Chuck section. (Figs. 4 to 11) and remove Barrel cover complete and Barrel section. (Figs. 13 and 14)
2) Disassemble Handle section and Controller from the machine as illustrated in Figs. 46 to 48.
3) Disassemble the rear side of Motor housing in the order of Figs. 50 to 52.
5x25 Tapping
screw (2 pcs.)
Rear cover
Motor
housing
Motor housing
Fan 90
M8-12 Hex nut
Remove the parts in the rear
side of Motor housing as
illustrated above.
M8 Socket bit
(12mm)
Cordless
impact driver
12mm
Holding Fan 90 with gloved hand,
remove M8-12 Hex nut using cordless
impact driver with M8 Socket bit.
Remove rear cover from
Motor housing. Note: Turn M8-12 Hex nut clockwise.
Fan guide
Fan 90
Flat Washer 8
M8x12 Hex nut
Fig. 50 Fig. 51 Fig. 52
ASSEMBLY
Do the reverse step of Disassembling. Refer to Figs. 49 to 46.
Cord clamp base
Power supply cord
Cord clamp
Lever up Controller's tabs
with slotted screwdrivers.
Controller is separated from
Motor housing.
Controller and Power supply cord
can be replaced.
Controller
Controller
slotted screwdrivers
Fig. 48 Fig. 49
3) Controller and Power supply cord can be disassembled as illustrated in Figs. 48 and 49.
[3] DISASSEMBLY/ASSEMBLY
[3] -7. Switches, Controller, Power Supply Cord (cont.)

P 17/ 23
[3] -8. Motor Section (cont.)
Repair
DISASSEMBLY
ASSEMBLY
Fig. 55
Separate Motor housing from Crank
housing complete. as illustrated above.
So, Armature comes out together with
Crank housing complete.
Disassemble Gear housing complete
together with Armature from Crank
housing complete. (Fig. 56)
Disassemble Armature from
Gear housing complete with
1R045 and 1R346.
Crank housing
complete
Crank housing
complete
Motor housing
Gear housing complete
Armature
Do the reverse step of Disassembly.
Armature
Armature
1R045
1R346
6) Armature can be disassembled as illustrated in Fig. 55.
Fig. 54 (HR4510C and HR4511C only)
Slotted screwdriver
Crank housing cover
Remove Crank Housing
Cover and Active Dynamic
Vibration Absorber
Remove M6x30 Hex
socket head bolts.
Active Dynamic
Vibration Absorber
M6x30 Hex socket
head bolt (4 pcs.)
Fig. 53
Hook Spiral spring's tail to Pin of
Brush holder unit in order to
disconnect Carbon brush from
Armature's commutator.
Spiral spring for pressing Carbon
brush toward Commutator
Carbon brush Carbon brush
PinPin
4) Disconnect Carbon brush from Armature's commutator. (Figs. 53)
5) Regarding HR4510C and HR4511C, remove Active Dynamic Vibration Absorber before separating Motor housing
from Crank housing complete. (Fig. 54) Armature can be disassembled as illustrated in Fig. 55.

P 18/ 23
[3] DISASSEMBLY/ASSEMBLY
[3] -9. Gear Section
Repair
ASSEMBLY
Do the reverse step of Disassembly illustrated in Figs. 56 and 57. Refer to Fig. 58 when assembling Gear section.
Helical gear 36
Spur gear 19
Key 5
Crank shaft
Protrusion
Face the protrusion side of Helical gear
36 to Gear housing installation side
when assembling Helical gear 36.
Otherwise, Helical gear 36 interferes
with Torque limiter's Rotation.
Gear Housing
Installation Side
Torque limiter
Fig. 58
Fig. 56
Fig. 57
After removing Helical gear 36,
Torque limiter assembly can be
removed.
Remove Spur gear 19 and
Key 5 from Crank shaft.
After removing
Flat washer 10,
disassemble
Retaining ring
S-14.
Retaining
Ring S-14
Retaining
ring S-17
Remove Crank shaft by carefully
striking the specific position of Crank
housing complete as illustrated right
while keeping Connecting rod in right
angle to the removing direction of
Crank shaft.
Otherwise, Connecting rod
may be broken.
Ball bearing
6303LLU
Flat washer 10
Flat washer 10 is left in Gear housing
complete in the step of Fig. 55.
1R291 Helical gear 36
Spur gear 19
Key 5 (2pcs.)
Torque limiter
assembly
DISASSEMBLY
Crank shaft
Connecting
rod
1) Disassemble the following parts from Crank housing complete.
* Chuck section (Figs. 4 to 11) * Barrel section (Figs. 13 and 14) * Handle section and Controller (Figs. 46 to 48)
* Motor section (Figs. 50 to 55)
After removing the above parts, Gears and Crank shaft are left in Crank housing complete.
2) Disassemble Gears and Crank shaft from Crank housing complete as illustrated in Figs. 56 and 57.

P 19/ 23
[3] DISASSEMBLY/ASSEMBLY
[3] -10. Handle Section (HR4511C: with Vibration absorbing handle)
Repair
ASSEMBLY
Facing the bow portion of Dust cover
to the upper side of the machine,
assemble Dust cover to Handle.
Dust cover support
Handle
Handle base
Do the reverse step of Disassembly. Refer to Figs. 60 to 58.
Refer to Fig. 62 when assembling Dust cover and Dust cover support to Handle.
Facing Triangle mark to the
upper side, insert Dust cover
support into Dust cover.
Upper side
Lower side
Dust cover
5x40 Tapping
screw (2 pcs.)
Flat washer 5
Fig. 62
Fig. 60 Fig. 61Fig. 59
Shoulder
sleeve 19
5x25 Tapping screw
5x40 Tapping screw (2 pcs.)
Flat washer 5
Handle
Handle base
Dust cover support
Dust cover
Handle cover
Separate Handle section from the machine
by unscrewing 5x25 Tapping screws. Remove another two
5x25 Tapping screws
to disassemble Handle
in the next step.
Remove 5x40 Tapping screws.
The several parts are separated from
Handle base as illlutrated above.
Handle cover can be removed
as the left Illustration in Fig. 46.
Compression spring 11
Spring guide
Crank cap cover
After removing Crank cap cover, Spring
guide with Compression spring 11 can be
removed from Crank housing complete.
5x25 Tapping
screw (6 pcs.)
DISASSEMBLY
1) Vibration absorbing handle consists of the following main parts.
* Handle base * Dust cover and Dust cover support
* Compression spring 11 (functions as a Vibration absorber) * Handle with Handle cover
2) Disassemble in the order from Figs. 59 to Fig. 61 when replacing the electrical parts in Handle section.

P 20/ 23
[3] DISASSEMBLY/ASSEMBLY
[3] -11. Fastening Torque
Repair
131 M8-12 Hex nut
15 M6x30 Hex socket
head bolt (4 pcs.) 64 M6x30 Hex socket
head bolt (4 pcs.)
78 M4x12 Pan
head screw
Fan 90
(Armature Fan)
Gear housing
complete
Crank housing
complete
Barrel complete
Crank cap
Crank lever
Retainer plate
Motor housing
Fasten the bolts to the fastening torque listed in Fig. 63.
Note: Apply adhesive (ThreeBond 1342 or Loctite 242) to the thread of M4x12 Pan head screw (Item No. 78).
Item No. Fastening torque Q'tyDescription
15 4 7.8 - 11.7 N.mM6x30 Hex socket head bolt
M6x30 Hex socket head bolt
M4x12 Pan head screw
64
78
44.9 - 7.8 N.m
131 1
1
1.8 - 3.5 N.m
1.5 - 2.3 N.m
M8-12 Hex nut
Fig. 64
[4] Maintenance
When replacing carbon brush, it is recommended to do replace the following parts (Fig. 64) and apply appropriate amount
of lubricants (Figs. 1 to 3) at the same time for longer service life of the machine.
1. Tool holder cap
22. X Ring 21
23. Fluoride ring 28 on Impact bolt
24. O Ring 23
39. O Ring 27 on Striker
49. O Ring 27 on Piston
122 23 24 39 49
(Impact bolt) (Striker) (Piston)
Fig. 63