Hitachi G 13SR Manual

POWER TOOLS
TECHNICAL DATA
AND
SERVICE MANUAL
DISC GRINDER
G 13SR
SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT
LIST No. E238 May. 2000
G
MODEL
G 13SR

Page
CONTENTS
[ Business Section ]
1. PRODUCT NAME••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••1
2. MARKETING OBJECTIVE••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••1
3. APPLICATIONS•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••1
4. SELLING POINTS•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••1
5. SPECIFICATIONS•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••2
6. COMPARISONS WITH SIMILAR PRODUCTS••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••3
6-1. Specification Comparisons•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••3
6-2. Comparisons in Torque vs. Rotation Speed and Stator Coil Temperature Rise•••••••••••••••••••••••••••4
7. PRECAUTIONS IN SALES PROMOTION •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••5
7-1. Handling Instructions•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••5
7-2. Caution on Name Plate ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••5
7-3. Precautions on Usage•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••6
8. PRECAUTIONS IN DISASSEMBLYAND REASSEMBLY••••••••••••••••••••••••••••••••••••••••••••••••••••••••••7
8-1. Disassembly of the Armature•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••7
8-2. Reassembly of the Stator Ass’y•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••7
8-3. Disassembly of the Gear •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••7
8-4. Precautions on Reassembly••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••8
8-5. Amount of Lubricant••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••8
8-6. Tightening Torque of Each Screw or Nut•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••8
8-7. Wiring Diagram•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••9
8-8. Remaining Reassembly••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••9
8-9. Insulation Tests••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••9
8-10. No-Load Current Value••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••9
9. STANDARD REPAIR TIME (UNIT) SCHEDULES••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••10
[ Appendix ]
Assembly Diagram for G 13SR•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••11
Notice for use
Specifications and parts are subject to change for improvement.
Refer to the Hitachi Power Tool Technical News for further information.

--- 1 ---
1. PRODUCT NAME
Hitachi Disc Grinder, Model G 13SR 125 mm (5")
2. MARKETING OBJECTIVE
In order to compete with maker C which has introduced an economy series of the slide-switch type disc grinder to
the market, Hitachi has developed the new Model G 13SR, which is based on the G 12SR. This follows
comprehensive overall productivity improvements to enhance the competitive power of our compact disc grinders
in export sales.
The performance and other features of Model G 13SR are basically the same as for Model G 12SR, except for the
wheel size and gear ratio.
3. APPLICATIONS
•Removal of casting fin and finishing of various types of steel, bronze, aluminum, and other metallic materials
and castings
•Grinding of welds, or sections cut by acetylene torch
•Cutting steel bars, steel pipes, shaped steel, and various other types of steel
•Cutting of concrete, stone, brick, tile, and similar materials
4. SELLING POINTS
Convenient slide type switch
for easy on/off switching
Convenient tool rest
15˚ forward-angled side
handle ensures better
control and efficient work
Powerful motor with maximum output of 800 W
(against maker C's model with 620 W)

--- 2 ---
5. SPECIFICATIONS
Item Model
A, 36, Q, BF
Depressed
center
wheel
Dimensions
Max. practical
peripheral speed
Type
AC single phase 50 or 60 HzPower source
Voltage (V)
Voltage, current and input
10,000 /min.No-load speed
220
230
Current (A)
2.9
2.7
Input (W)
600
Type of motor
Slide switchType of switch
Material: Housing (green)
Tail cover (black)
Gear cover, Packing gland
Inner cover
Painting: Gear cover, Packing gland
Inner cover
Enclosure
1.6 kg (3.5 lbs.)Net*1)
3.0 kg (6.6 lbs.)Gross
Corrugated cardboard boxPackaging
••••• Glassfiber reinforced polycarbonate resin
Standard accessories*2) Side handle ••••••••••••••••• 1
Wrench ••••••••••••••••••••••• 1
4,800 m/min. (15,800 ft/min., 80 m/s)
with DSA approved Red Belt on the label
G 13SR
O.D. 125 mm (5")
x Thickness 6 mm (1/4")
x I.D. 22 mm (7/8")
Offset amount : 4.8 mm (3/16")
*1) Net weight excludes cord, side handle, depressed center wheel, wheel nut, wheel washer and wheel guard.
*2) Standard accessories are subject to change without prior notice.
Weight
AC single phase commutator motor
••••• Aluminium alloy die casting
••••• Metallic silver

--- 3 ---
6. COMPARISONS WITH SIMILAR PRODUCTS
6-1. Specification Comparisons
Maker HITACHI
Model G 13SR
Wheel diameter 125 (5")
mm
Power input 600
Power output 390
Max. power output 800
No-load speed 10,000
Grip diameter
Grip circumference 207 (8-5/32")
Dimensions
261 (10-1/4")
H60 (2-3/8")
W67 (2-5/8")
Weight* 1.6 (3.5 Ibs.)
(Actual weight) (1.6) (3.5 Ibs.)
W
W
W
/min.
mm
mm
mm
mm
mm
kg
L
G 10SR/G 12SR
100/115 (4"/4-1/2")
550
360
800
11,000
63 (2-15/32")
207 (8-5/32")
261 (10-1/4")
60 (2-3/8")
67 (2-5/8")
1.6 (3.5 Ibs.)
(1.6) (3.5 Ibs.)
62 (2-7/16")
C
125 (5")
540
300
620
10,000
56 (2-7/32")
195 (7-11/16")
256 (10-1/8")
70 (2-3/4")
81 (3-3/16")
1.4 (3.1 Ibs.)
(1.5) (3.3 Ibs.)
65 (2-9/16")
WL
* Weight excludes cord, side handle, depressed center wheel, wheel nut, wheel washer and wheel guard.
Grip circumference

--- 4 ---
6-2. Comparisons in Torque vs. Rotation Speed and Stator Coil Temperature Rise
Fig. 1 shows comparisons of the rotation speed and the stator coil temperature rise between a competitive model
with respect to torque. Torque represents the magnitude of load, i.e., the amount of pressing force, cutting depth
and forward force in actual cutting jobs. This shows that a powerful motor is less likely to burn-out because it has
both a minimum drop of rotation speed even at a greater torque and a lower stator coil temperature rise at the
same torque.
Fig. 1 Comparisons in torque vs. rotation speed and stator coil temperature rise
Fig. 1 indicates:
1 The rotation speed of maker C's model at the same torque is low and the stator coil temperature rise is high,
which causes low motor power.
2 The rotation speed of HITACHI G 13SR at the same torque is high and the stator coil temperature is low. As
the speed and the temperature are well balanced, HITACHI G 13SR ensures excellent performance for
different jobs regardless of the magnitude of load.
HITACHI G 10SR/G 12SR
HITACHI G 13SR
Rotation speed of spindle HITACHI G 10SR/G 12SR
CHITACHI G 13SR
400
300
200
100
0
0
2,000
4,000
6,000
8,000
10,000
12,000
C
: Burn-out point
Stator coil temp.
Rotation speed of spindle (/min.) Stator coil temp. rise (K)
Torque (Load)

--- 5 ---
7. PRECAUTIONS IN SALES PROMOTION
In the interest of promoting the safest and most efficient use of the Model G 13SR Disc Grinder by all of our
customers, it is very important that at the time of sale, the salesperson carefully ensures that the buyer seriously
recognizes the importance of the contents of the Handling Instructions, and fully understands the meaning of the
precautions listed on the Name Plate or Caution Plate attached to each tool.
7-1. Handling Instructions
Although every effort is made in each step of design, manufacture and inspection to provide protection against
safety hazards, the dangers inherent in the use of any electric power tool cannot be completely eliminated.
Accordingly, general precautions and suggestions for the use of electric power tools, and specific precautions and
suggestions for the use of the disc grinders are listed in the Handling Instructions to enhance the safe, efficient
use of the tool by the customer. Salespersons must be thoroughly familiar with the contents of the Handling
Instructions to be able to offer appropriate guidance to the customer during sales promotion.
7-2. Caution on Name Plate
Each tool is provided with a Name Plate which lists the following basic safety precaution in the use of the tool.
CAUTION
Read thoroughly HANDLING INSTRUCTIONS before use.
For China, Hong Kong

--- 6 ---
7-3. Precautions on Usage
(1) The wheel guard must be aligned in relation to the side handle mounting position.
As illustrated in Figs. 2 and 3 the customer should be instructed that the wheel guard mounting angle must be
aligned and fixed in accordance with the side handle mounting position so that the operator's hand will not
contact the depressed center wheel.
Fig. 2 Fig. 3
(2) Never press the pushing button while the depressed center wheel is rotating.
If the pushing button (illustrated in Figs. 2 and 3) is pressed while the depressed center wheel is rotating, the
spindle will stop immediately. In such a case, there is a danger that the wheel nut may be loosened.
Eventually the depressed center wheel may fly off unexpectedly to cause possible serious injury.
Side handle Pushing button
Wheel guard

--- 7 ---
8. PRECAUTIONS IN DISASSEMBLY AND REASSEMBLY
The [Bold] numbers in the descriptions below correspond to the numbers in the Parts Lists and exploded
assembly diagrams for G 13SR.
8-1. Disassembly of the Armature
(1) Loosen the Machine Screw (W/SP. Washer) M5 x 16 [26] and remove the Wheel GuardAss'y [28].
(2) Remove the Brush Caps [40], and take out the Carbon Brushes [41].
(3) Loosen the Tapping Screws D5 x 25 [1], and remove the Gear Cover Ass'y [4]. Separate the Inner Cover [9]
from the Housing Ass'y [36] with a flat-blade screwdriver, and remove the Inner Cover [9] together with the
Armature [10].
(4) Holding the Armature [10], loosen the Special Nut M7 [5] with a wrench, and remove the Pinion [6].
(5) Support the Inner Cover [9] with a tubular jig (inner diameter 63 --- 72 mm is recommended), and push down
on the armature shaft with a hand press to remove the Armature [10]. (See Fig. 4.)
8-2. Disassembly of the Stator Ass'y
(1) After removing the Armature [10], disconnect the lead
wires of the Stator Ass'y [12] from the Slide Switch [44].
Then, remove the Brush Terminals [13] from the Brush
Holders [42].
(2) Loosen the Hex. Hd. Tapping Screws D4 x 70 [11], and
remove the Stator Ass'y [12].
8-3. Disassembly of the Gear
(1) Loosen the Seal Lock Screw (W/SP. Washer) M4 x 12 [23],
and remove the Packing Gland [22] together with the
Spindle [25], and Gear [17] from the Gear Cover Ass'y [4]
in a single body.
(2) As illustrated in Fig. 5, support the angled surface of the
Gear [17] with a J-129 gear puller (special repair tool,
Code No. 970905), rest the J-129 gear puller on a J-130
sleeve (special repair tool, Code No. 970907), and push
down on the tip of the Spindle [25] with a hand press to
remove the Gear [17].
Fig. 4
Fig. 5
Push down
[9] Inner Cover
Dia. 63 --- 72 mm
[10] Armature
Armature
shaft
Push
J-129 Gear puller

--- 8 ---
8-4. Precautions on Reassembly
1) Thoroughly coat the grease (Hitachi Motor Grease N.P.C. SEP-3A, Code No. 930035, is recommended) on the
gear teeth of the gear and pinion. Special attention must be given to ensure that the grease is applied properly
all the way to the base of each gear teeth.
Failure to do so could result in early wear and/or damage to the gear and pinion.
2) Liberally moisten the inner circumference of the felt packing with machine oil:
Failure to properly moisten the inner circumference of the felt packing could cause early wear and/or damage of
the ball bearing.
3) When replacing the gear cover assembly with a new one, apply mixed oil into the inner roller of the needle
bearing (metal).
Mixed oil: A mixture of Hitachi Power Tool Grease No. 2 (unilube No. 00, Code No. 939302) and turbine
oil is recommended.
Mixture ratio: 1:1 (Weight ratio)
Supply amount: 0.5 cc
8-5. Amount of Lubricant
•Pinion chamber of Gear Cover Ass'y [4] (supply from inner cover side)••••••••••••••••• 8 gr. of N.P.C. SEP-3A
grease (Code No. 930035)
Also, thoroughly apply grease on the gear teeth of the gear and pinion. (See Para. 8-4.)
•Needle bearing (Metal) ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• Mixed oil 0.5 cc
Mixed oil: Hitachi Power Tool Grease No. 2 (Code No. 939302) and turbine oil.
Mixture ratio: 1:1 (Weight ratio)
8-6. Tightening Torque of Each Screw or Nut
•Slotted Hd. Screw (Seal Lock) M4 [7]
and Seal Lock Screw (W/SP. Washer) M4 [18] [23] •••••••••••1.8 0.5 N•m (18 4 kgf•cm, 1.3 0.3 ft-lbs.)
•Tapping Screws D4 [11] [43] [46] [52] ••••••••••••••••••••••••••••• 2.0 0.5 N•m (20 5 kgf•cm, 1.5 0.4 ft-lbs.)
•Tapping Screws D5 [1] ••••••••••••••••••••••••••••••••••••••••••••••••••• 2.9 0.5 N•m (30 5 kgf•cm, 2.2 0.4 ft-lbs.)
•Special Nut M7 [5] •••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 6.4 1.0 N•m (65 10 kgf•cm, 4.7 0.7 ft-lbs.)
•Flat Hd. Screw M4 [34] ••••••••••••••••••••••••••••••••••••••••••••••••••• 0.6 N•m (6 kgf•cm, 0.4 ft-lbs.)
+ 0.2
0
+ 0.3
0 + 3 0

--- 9 ---
8-7. Wiring Diagram
(1) For China
(2) For other countries Switch
Fig. 6
Switch
Cord
Noise
suppressor
Armature
Choke coil
Stator
Fig. 7
Cord
Stator
Armature
8-8. Remaining Reassembly
Remaining reassembly can be accomplished by following the disassembly procedures in reverse.
8-9. Insulation Tests
On completion of disassembly and repair, measure the insulation resistance and conduct the dielectric strength
test.
Insulation resistance: 7 M or more with DC 500 V Megohm Tester.
Dielectric strength: AC 4000 V/1 minute, with no abnormalities •••••••••••••• 220 V --- 230 V
8-10. No-Load Current Value
After no-load operation for 30 minutes, the no-load current value should be as follows:
Voltage (V)
Current (A) (max.)
220 230
1.3 1.2

--- 10 ---
9. STANDARD REPAIR TIME (UNIT) SCHEDULES
MODEL 10 20 30 40 50 60 min.
Fixed Variable
G 13SR Work Flow
Slide Switch
Cord
Tail Cover Housing Ass'y
Stator Ass'y
Slide Bar
Pinion
Bearing Cover
Ball Bearing
(608 VVMC)
Inner Cover
Armature
Ball Bearing
(626 VVMC)
Bearing Cover
Ball Bearing
(6001 VVCM)
Felt Packing
Packing Gland
Spindle
Flinger
Pushing Button
Gear Cover
Ass'y
Lock Pin
Gear
Wheel Guard
Ass'y
General Assembly

--- 11 ---
Assembly Diagram for G 13SR

--- 12 ---
PARTS
G 13SR
: ALTERNATIVE PARTS
ITEM
NO. CODE NO. DESCRIPTION NO. USED
REMARKS
1 937-807 TAPPING SCREW D5X25 1
2 302-149 GUARD PLATE 1
3 301-944 PUSHING BUTTON 1
4 314-125 GEAR COVER ASS'Y 1 INCLUD.3,16
5 301-941 SPECIAL NUT M7 1
6 301-939 PINION 1
7 314-430 SLOTTED HD. SCREW (SEAL LOCK) M4X10 2
8 608-VVM BALL BEARING 608VVC2PS2L 1
9 301-935 INNER COVER 1
10 360-163E ARMATURE 220V-230V 1
11 982-021 HEX. HD. TAPPING SCREW D4X70 2
* 12 340-187E STATOR ASS'Y 220V 1 INCLUD.13
* 12 340-477G STATOR ASS'Y 220V 1 INCLUD.13 FOR CHN
13 931-867 BRUSH TERMINAL 2
14 980-865 WASHER (A) 1
15 626-VVM BALL BEARING 626VVC2PS2L 1
16 301-943 LOCK PIN 1
17 301-940 GEAR 1
18 987-201
SEAL LOCK SCREW (W/SP. WASHER) M4X10 3
19 938-058 BEARING COVER (B) 1
20 600-1VV BALL BEARING 6001VVCMPS2L 1
21 301-946 FELT PACKING 1
22 301-947 PACKING GLAND 1
23 987-203
SEAL LOCK SCREW (W/SP. WASHER) M4X12 4
24 940-220 WOODRUFF KEY 2.5X8 1
25 319-117 SPINDLE 1
26 308-386
MACHINE SCREW (W/SP. WASHER) M5X16(BLACK) 2
27 301-949 SET PLATE 1
28 319-116 WHEEL GUARD ASS'Y 1 INCLUD.26,27
29 937-817Z WHEEL WASHER 1
30 994-324 WHEEL NUT M14 1
31 301-938 GEAR AND PINION ASS'Y 1 INCLUD.6,17
32 938-299 SPRING 1
33 982-033 SLIDE BAR 1
34 949-322 FLAT HD. SCREW M4X10 (10 PCS.) 1
35 994-298 SLIDE KNOB (C) 1
36 315-493 HOUSING ASS'Y 1 INCLUD.42
* 37 NAME PLATE 1
38 307-010 BEARING BUSHING 1
39 HITACHI LABEL 1
40 937-847 BRUSH CAP 2
41 999-021 CARBON BRUSH (1 PAIR) 2
42 937-846 BRUSH HOLDER 2
43 305-720 TAPPING SCREW (W/FLANGE) D4X12 1
44 980-778 SLIDE SWITCH (2P PILLAR TYPE) 1
45 982-044 SWITCH HOLDER 1
46 984-750 TAPPING SCREW (W/FLANGE) D4X16 4
* 47 994-273 NOISE SUPPRESSOR 1 FOR CHN
* 48 959-144 TERMINAL 50051 (10 PCS.) 1 FOR CHN
* 49 981-373 TUBE (D) 2 FOR CHN
50 953-327 CORD ARMOR D8.8 1
*
4--- 00

--- 13 ---
PARTS
G 13SR
ITEM
NO. CODE NO. DESCRIPTION NO.
USED
REMARKS
51 315-494 TAIL COVER 1
52 307-811
TAPPING SCREW (W/FLANGE) D4X16 (BLACK) 1
53 500-409Z CORD 1 (CORD ARMOR D8.8)
* 54 960-266 CORD CLIP 1
* 54 308-094 CORD CLIP 1 FOR CHN
55 981-373 TUBE (D) 2 FOR CORD
: ALTERNATIVE PARTS
*
4--- 00

--- 14 ---
601 302-142 SIDE HANDLE 1
602 316-822 D. C. WHEELS 125MM A36Q (25 PCS.) 1
603 310-338 SUPER WASHER 1
CODE NO.
: ALTERNATIVE PARTS
*
STANDARD ACCESSORIES
G 13SR
ITEM
NO. CODE NO. DESCRIPTION NO.
USED
REMARKS
501 938-332Z WRENCH 1
502 318-312 SIDE HANDLE 1
4--- 00
Printed in Japan
(000425 N)
OPTIONAL ACCESSORIES
ITEM
NO. DESCRIPTION NO.
USED
REMARKS