Hitachi HAMMER H 65SC Manual

POWER TOOLS
TECHNICAL DATA
AND
SERVICE MANUAL
HAMMER
H 65SC
SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT
LIST No. E451 Nov. 1999
H
MODEL
H 65SC

REMARK:
Throughout this TECHNICAL DATA AND SERVICE MANUAL, a symbol(s)
is(are) used in the place of company name(s) and model name(s) of our
competitor(s). The symbol(s) utilized here is(are) as follows:
Symbols Utilized Competitors
Company Name Model Name
MAKITA HM1303
C-2 MAKITA HM1500
C-1

Page
CONTENTS
[ Business Section ]
1. PRODUCT NAME
••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••
1
2. MARKETING OBJECTIVE
••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 1
3. APPLICATIONS
••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 1
4. SELLING POINTS
•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 1
4-1. Selling Point Descriptions
••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 2
5. SPECIFICATIONS
••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••
3
5-1. Optional Accessories
••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 4
6. COMPARISONS WITH SIMILAR PRODUCTS
••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••
6
6-1. Specification Comparisons
•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 6
6-2. Demolition Performance Comparisons •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 6
7. PRECAUTIONS IN SALES PROMOTION•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 7
7-1. Handling Instructions
•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••
7
7-2. Caution Plate
••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 7
7-3. Oil Supply
••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••
7
7-4. Impact Performance at Low Temperatures
••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 8
8. REFERENCE INFORMATION
••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••
9
8-1. Structure of the Main Body ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 9
8-2. Stop Lever [Tool Retainer] ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 9
8-3. Movement of the Stop Lever •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 10
8-4. No-load Striking Preventive Mechanism ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 10
[ Service Section ]
9. REPAIR GUIDE •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 10
9-1. Precautions and Suggestions for Disassembly and Reassembly of the Main Body ••••••••••••••••••••• 10
9-1-1. Disassembly ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 10
9-1-2. Reassembly •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 13
9-1-3. Screw Locking Agent TB1401 •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 16
9-1-4. Tightening Torque ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 16
9-1-5. Internal Wiring •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 16
9-1-6. Insulation Tests ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 17
9-1-7. No-Load Current Value •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 17
10. STANDARD REPAIR TIME (UNIT) SCHEDULES •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 18
[ Appendix ]
Assembly Diagram for H 65SC •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 19
Notice for use
Specifications and parts are subject to change for improvement.
Refer to Hitachi Power Tool Technical News for further information.

--- 1 ---
1. PRODUCT NAME
Hitachi Electric Hammer, Model H 65SC
2. MARKETING OBJECTIVE
The Model H 65SC is a double-insulated version of the existing single-insulated Model PH-65A. It has a
recirculating lubricating system. Demolishing and chipping power is comparable to that of the PH-65A, as is the
basic structure. The main features of the Model H 65SC is as follows:
(1) Highest demolition performance in this class.
(2) Durable, Aluminum-die-cast Housing for longer service life.
(3) Lower consumption motor design.
3. APPLICATIONS
Demolishing of concrete and similar materials.
Groove and channel digging in concrete.
Groove and channel digging in asphalt and gravel roads.
Tamping/compacting of asphalt and graveled roads.
Cutting of asphalt.
[Typical Applications]
Constructions work, piping/wiring work, water supply/drain work, etc.
4. SELLING POINTS
Maker •Model Weight Overall length
HITACHI H 65SC 15 kg (33.1 lbs.) 647 mm (25-15/32")
HITACHI PH-65A 15 kg (33.1 lbs.) 642 mm (25-9/32")
C-1 14 kg (30.9 lbs.) 675 mm (26-37/64")
C-2 17 kg (37.5 lbs.) 647 mm (25-15/32")

--- 2 ---
Largest demolition performance in this class.
4-1. Selling Point Descriptions
4-1-1. Largest demolition performance in this class
Demolition performance is 1.1 to 1.3 times larger than that of similar products thanks to the maximum 39.5 J
impact energy and efficient striking.
Maker •Model Ratio of demolished weight (%)
HITACHI H 65SC 100
HITACHI PH-65A 100
C-1 80
C-2 92
Internal double-insulation construction
with rugged aluminum frame.
Automatic lubricator permits operating over
extended periods without supplying oil.

--- 3 ---
5. SPECIFICATIONS
H 65SC
Power source
Voltage (V)
Motor type
Insulation structure
Enclosure
Switch
Type of handles
Full-load current
Power input
Striking speed
Weight
Packaging
Standard accessories
Single-phase AC 50/60 Hz
110, 115, 230, 240
AC single-phase series commutator motor
Double insulation
Materials: Aluminum alloy die casting
Cast aluminum alloy
Glass-fiber reinforced plastic resin
Paint: Hammer-net silver green and black
Trigger switch (with stopper)
D-shaped handle and side handle
11.8 A (110 V), 11.4 A (115 V), 5.7 A (230 V), 5.4 A (240 V)
1,240 W
1,800 /min.
1,400 /min.
Product: 15.0 kg (33.1 lbs.); excluding cord
Packed: 23.5 kg (51.8 lbs.)
Corrugated cardboard box with steel tool case
Hex. bar wrench (for M6) •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 1
Hex. bar wrench (for M8) •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 1
Steel tool case ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 1
Side handle ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 1
Bull point •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 1
Oil feeder •••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 1
Wrench ••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••• 1
Item
No-load
Full-load

--- 4 ---
+
+
+
+
5-1. Optional Accessories
1. Demolition work
(1) Bull point
2. Grooving and chiseling work
(1) Cold chisel
3. Cutting and stripping work (asphalt cutting, etc.)
(1) Cutter
4. Digging (substitute pick-ax)
(1) Scoop
Overall length
410 mm (16-9/64") Code No. 944961
Overall length
410 mm (16-9/64")
Code No.
944962
Width
75 mm (2-61/64")
Overall length
410 mm (16-9/64")
Code No.
944964
Overall length
550 mm (21-21/32")
Code No.
944967

--- 5 ---
(Note)
Code numbers listed above are subject to change. Please refer to periodic Technical News Bulletins.
++
5. Tamping work
(1) Rammer (2) Shank (SDS-max shank type)
Overall length
250 mm (9-27/32")
Code No.
944966
Code No. 944965
Ext. Dia. 200 mm dia.
(7-7/8")
6. Electric hammer oil
Capacity
1 liter (0.26 gallon)
Code No.
955009

--- 6 ---
6. COMPARISONS WITH SIMILAR PRODUCTS
6-1. Specification Comparisons
Maker
Model name
Power input
Full-load impact rate
Dimensions
Striking energy per stroke
Insulation structure
No-load noise level
Weight (without cord)
HITACHI
Length
Height
Width
W
/min
mm
mm
mm
J
---
dB(A)
kg
H 65SC
1,240
1,400
647
(25-15/32")
235
(9-1/4")
120
(4-23/32")
39.5
Double
insulation
92
15.0
(33.1 lbs.)
PH-65A
1,240
1,400
642
(25-9/32")
231
(9-3/32")
120
(4-23/32")
39.5
Single
insulation
92
15.0
(33.1 lbs.)
C-1
1,300
1,450
675
(26-37/64")
212
(8-11/32")
120
(4-23/32")
39.5
Double
insulation
94
14.0
(30.9 lbs.)
C-2
1,430
1,300
647
(25-15/32")
215
(8-15/32")
---
(---)
40.3
Double
insulation
93
17.0
(37.5 lbs.)
6-2. Demolition Performance Comparisons
The data shown in Fig. 1 are obtained in actual factory tests, and are for reference only. Demolished amount may
vary in accordance with operating conditions, operator skill, etc.
Fig. 1
75 100 125 150
178
178
142
164
175
H65SC
PH-65A
C-1
C-2
Demolished amount
(kg/30 min.)
Demolished weight for 30 min. (kg)
At rated
voltage

--- 7 ---
OIL GAUGE CAP
Feed oil, before oil is invisible
in the oil gauge by holding the
body upright.
7. PRECAUTIONS IN SALES PROMOTION
In the interest of promoting the safest and most efficient use of the Model H 65SC Electric Hammer 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 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 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 Electric Hammer 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 Plate
Each Model H 65SC unit is provided with a Caution Plate (illustrated below) which lists basic safety precautions in
its use. Carefully ensure that the customer fully understands and follows these precautions before using the tool.
For the U.S.A. and Canada
Cautions on Oil Gauge:
-- WARNING -- To reduce the
risk of injury,
user must read and understand instruction manual.
AVERTISSEMENT Afin de rèduire le risque de
blessures, l'utilisateur doit lire et
bien comprendre le mode d'emploi.
Hitachi Koki
7-3. Oil Supply
As the Model H 65SC is equipped with a built-in oil tank, there is no need for manual oiling of the tool prior to and
during operation.
To prevent possible oil staining of the steel carrying case during shipping, only approximately 10 cc of oil is
supplied to the oil tank when the tool is shipped from the factory. Accordingly, it is very important that the
customer be instructed to remove the Oil Gauge and fill the oil tank with the standard accessory oil at the
time of purchase.
If lubricant for high-speed rotating and sliding parts
such as the needle bearings, piston, etc. is depleted,
it could cause damage such as jamming of sliding
parts, early damage, etc.

--- 8 ---
Instruct the customer to check the amount of oil periodically by holding the tool upright, as illustrated below, and
observing the oil level in the Oil Gauge. When the oil level drops to a point approximately 3 mm (7/64") or less
from the bottom of the Oil Gauge, remove the Oil Gauge and replenish the oil.
Fig. 2
Oil Gauge
Hold the tool
upright, and
check the amount
of oil.
3 mm (7/64")
Replenish oil when level
is approx. 3 mm (7/64") or less
from bottom of Oil Gauge.
Under average operating conditions, approximately 3 cc of oil will be consumed per hour of operation. The
standard accessory oil feeder contains 120 cc of oil; when it is added to the oil tank, the oil tank will be filled with
approximately 130 cc of oil. When it becomes necessary to replenish the oil, the customer should be cautioned to
use Shell Omala Oil #150 without fail. To ensure that the appropriate oil is used, the customers should be urged
to purchase and use the optional accessory Hitachi Electric Hammer Oil, Code No. 955009, which is available in
one liter (0.26 gallon) containers.
7-4. Impact Performance at Low Temperatures
When starting the tool early in the morning when the ambient temperature is low or after the tool has not been
used for a long period of time, oil viscosity may be very high and may cause improper or even complete lack of
impact function even though the motor functions properly. In such a case, the customer should be instructed to
continue no-load operation for approximately 5 minutes to allow the tool to warm up. The tool should then
function normally.

--- 9 ---
8. REFERENCE INFORMATION
8-1. Structure of the Main Body
The primary structure of the Model H 65SC is similar with the Model PH-65A, as illustrated. (Fig. 3)
Fig. 3
8-2. Stop Lever [Tool Retainer] (Fig. 4 and Fig. 5)
(1) Clean, then smear the tool shank with
grease or machine oil. (Fig. 4)
(2) Rotate the stop lever 180˚in a
clockwise direction while pulling it
toward you. Next, insert the tool shank
into the hexagonal hole on the front
cover. (Fig. 4)
(3) Clamp the tool by turning the stop lever
by half a turn in the opposite direction.
(Fig. 5)
Fig. 4
Front Cover
Stop Lever
Shank Sleeve
Mouth
Striker
L Ring
Piston Pin
Final Gear
Crank Shaft
Gear Cover Ass'y
Counter Gear
Inner Cover
Switch Handle
Stator Ass'y
Armature Ass'y
Felt Holder (C)
Ass'yHousing Ass'y
Connecting Rod
Piston
Cylinder Case
Front Cover
2
1
3
Hold the tool with its flattened
part directed upward.
Tool Shank Stop Lever
Fig. 5
Stop Lever

--- 10 ---
8-3. Movement of the Stop Lever
After an extended period of use, the operation of the Stop Lever may become difficult due to incursion of concrete
powder or similar materials into its sliding portion. In such a case, apply oil into the sliding portion between the
Stop Lever and fitting portion of the Front Cover.
8-4. No-load Striking Preventive Mechanism
This machine is so constructed that when the bit end is lifted off the surface being worked, the striker is caught in
the mouth to prevent no-load striking; and when the striker comes off the mouth, a phase difference between the
piston and striker is utilized to reduce the striker's amplitude, thereby preventing the striker from striking the bit as
a double-preventive measure against no-load striking. When the striker is prevented from striking the bit, turn the
switch OFF; then the switch ON again with the bit lightly push the main body on the concrete surface so that the
equipment starts striking.
9. REPAIR GUIDE
9-1. Precautions and Suggestions for Disassembly and Reassembly of the Main Body
The [Bold] numbers in the descriptions below correspond to the item numbers in the Parts List and exploded
assembly diagram.
9-1-1. Disassembly
[NOTE] If it is difficult to loosen and remove the fixing bolts, use an appropriate heat gun, etc. to heat them to
approximately 80 ˚C (176 ˚F).
Disassembly of the Armature Ass'y [61]
(1) Loosen the four Seal Lock Hex. Socket Hd. Bolts M4 x 12 [70], remove the Cap Covers [65], Cap Rubbers
[66] and Brush Caps [67], and take out the Carbon Brushes [68]. At this time, be very careful not to lose the
disassembled parts.
(2) Loosen the four Nylock Hex. Socket Hd. Bolts M8 x 35 [22], and remove the Cylinder Case [20]. Next, after
loosening the Seal Lock Hex. Socket Hd. Bolt M8 x 16 [35], the Connecting Rod Ass'y [38] and Crank Washer
[39] can be disassembled. Leave the Striker [8] and Piston [11] as they are.
(3) Loosen the four Seal Lock Hex. Socket Hd. Bolts M6 x 25 [101], and take off the Handle and Handle Cover
Set [88]. Next, loosen the six Seal Lock Hex. Socket Hd. Bolts M6 x 45 [47], and disassemble the Gear Cover
[40] and Counter Gear [52]. Then, by inserting a flat-blade screwdriver or similar tool into one of the air vents
of the Inner Cover [45] and lifting it upwards, the Inner Cover [45], Armature Ass'y [61], Crank Shaft [37], and
related parts can be removed in a single body.
(4) As illustrated in Fig. 6, support the Inner Cover [45] with an appropriate tubular jig, and push down on the end
surface of the armature shaft with a hand press to separate the Armature Ass'y [61] from the Inner Cover [45].

--- 11 ---
Fig. 6
Press the end surface of the armature
with a hand press.
Tubular jig
Armature Ass'y [61]
Inner Cover [45]
Crank Shaft [37]
Disassembly of the Crank Shaft [37] section
First, remove the four Seal Lock Hex. Socket Hd. Bolts M5 x 16 [33] which fix the Bearing Cover [32]. Then, as
illustrated in Fig. 7, support the lower surface of the Inner Cover [45] with an appropriate tubular jig, align an
appropriate steel rod with the end surface of the Crank Shaft [37], and press down on the steel rod with a hand
press. The Ball Bearing 6205DDCMPS2L [31], Distance Ring (B) [43], Final Gear [42], two Woodruff Keys 4 x 16
[36], and Crank Shaft [37] can then be disassembled from the Inner Cover [45].
Press the end surface of the crank shaft
by fitting a steel rod with a hand press.
Ball Bearing [41]
Final Gear [42]
Inner Cover [45]
Crank Shaft [37] Tubular Jig
Fig. 7
Disassembly of remaining parts from the Inner Cover [45]
Loosen the three Seal Lock Hex. Socket Hd. Bolts M5 x 16 [33], and take out Bearing Cover (A) [48] and the
Ball Bearing 6203DDCMPS2L [49].
Disassembly of the Mouth [17] and related parts
First, remove the six Nylock Hex. Socket Hd. Bolts M8 x 30 [3], and separate the Front Cover [7] from the
Cylinder Case [20]. The Shank Sleeve [15], Damper [13], Mouth [17], Mouth Cover [16], Mouth Washer [18],
and Urethane Ring [19] can then be taken out.
Removal of the O-Ring [14]
As the O-Ring [14] is installed in the inner portion of the Shank Sleeve [15], it may be difficult to remove. As
illustrated in Fig. 8, pry the O-Ring [14] upward gently with a slender flat-blade screwdriver, being very careful
not to damage the surface of the O-Ring.

--- 12 ---
Removal of the Striker [8] and related parts
Remove the four Nylock Hex. Socket Hd. Bolts M8 x
35 [22], and separate the Cylinder Case [20] from the
Housing Ass'y [59]. From the Cylinder Case [20],
take out the Striker [8], Piston [11], and Connecting
Rod Ass'y [38] in a single body. Holding the Striker
[8] firmly in one hand, grasp the Connecting Rod
Ass'y [38] in the other hand and pull it forcefully to
separate it from the Striker. Finally, extract the Piston
Pin [10] from the Piston [11], and separate the Piston
from the Connecting Rod Ass'y [38].
Slender screwdriver
Fig. 8
O-Ring [14]
Shank
Sleeve [15]
Disassembly of the Stop Lever [1]
Push Damper (B) [6]
with two flat-blade screwdrivers. Overlap the end surface of the
Stop Lever [1] on the flange
portion of the Front Cover [7].
Stop Lever [1]
Lever Spring [5]
Damper (B) [6]
Spring
Case [4]
3 mm dia. hole
Steel rod
(3 mm or less dia.)
Fig. 9
Disassembly procedures are illustrated in Fig. 9. Pull the Stop Lever [1] outward in the direction indicated by the
arrow, and turn it slightly so that its end surface comes to rest on the flange portion of the Front Cover [7]. Next,
turn the Spring Case [4] so that the holes of the Spring Case are aligned with the Needle Roller [2]. Then, push
in Damper (B) [6] with flat-blade screwdrivers to compress the Lever Spring [5]. Finally, while keeping the Lever
Spring compressed, fit a 3 mm or less dia. steel rod into the hole of the Spring Case [4], and push out the Needle
Roller [2]. The Stop Lever [1], the Damper (B) [6], and the Lever Spring [5] can then be taken out.
How to remove the L-Ring [9]
The L-Ring [9] can be removed by prying it with a flat-blade screwdriver or manually, as shown in the following
figure. (Fig. 10)
Fig. 10
Needle Roller [2]

--- 13 ---
9-1-2. Reassembly
Reassembly can be accomplished by following the disassembly procedures in reverse. However, special
attention should be given to the following items.
(1) Reassembly of the Crank Shaft [37] section:
Press-fit the Ball Bearing 6205DDCMPS2L [31] into the Inner Cover [45], and fasten Bearing Cover [32] onto
the Inner Cover [45] with the four Seal Lock Hex. Socket Hd. Bolts M5 x 16 [33]. Support the inner race of the
Ball Bearing 6205DDCMPS2L [31] with an appropriate jig, and press-fit the Crank Shaft [37] into the Ball
Bearing. Next, insert Distance Ring (B) [43] and two Woodruff Keys 4 x 16 [36] into the Crank Shaft [37], and
press-fit the Final Gear [42] and the Ball Bearing 6302VVCMPS2L [41] with a hand press.
(2) Reassembly of the Armature Ass'y [61]:
Press-fit the Ball Bearing 6203DDCMPS2L [49] into the Inner Cover [45], and fasten Bearing Cover (A) [48]
onto the Inner Cover with the three Seal Lock Hex. Socket Hd. Bolts M5 x 16 [33].
(3) Reassembly of the Striker [8]: (Two possible methods) (Fig. 11)
A. After the Connecting Rod Ass'y [38] has been
assembled into the Housing Ass'y [59], mount
the Piston [11] and press it into the Striker [8].
B. Mount the Piston [11] onto the Connecting
Rod Ass'y [38], and push down on the
Connecting Rod Ass'y to press the Piston into
the Striker [8].
Push
Connecting Rod Ass'y [38]
Striker [8]
Piston [11]
Respiratory holes
Striker [8]
Housing Ass'y [59]
Connecting Rod Ass'y [38]
Push
Piston [11]
Respiratory holes
Fig. 11
Either of the two methods described above requires a pressing force of more than 30 kg. When a "hissing" sound
is heard, the Piston is properly inserted in the Striker. (The "hissing" is the sound of the compressed air escaping
from the Striker when the Piston reaches the respiratory chambers within the Striker.)

--- 14 ---
(4) Reassembly of the Oil Felt:
To replace the Oil Felt [79], follow the procedures described below.
Fig. 12
Slender-Tipped Rod
or Steel Wire
Fig. 13
Oil Felt [79]
Recess
Felt Holder (C) Ass'y [77]
Oil Felt [79]
Protruding amount:
10 --- 11 mm (0.39" --- 0.43")
1) As illustrated in Fig. 12, fit the wide end of the Oil Felt [79] into the oiling hole, and push it through with a
slender-tipped rod or steel wire.
2) When approximately 5 mm (0.2") of the Oil Felt [79] has been pushed through into the oil tank, grasp the
tip with pliers or a similar tool, and pull it into the oil tank so that 10 --- 11 mm (0.39" --- 0.43") remains
protruding into the crank case chamber side, as illustrated in Figs. 12 and 13.
3) As illustrated in Fig. 14, mount the Felt Holder (C)Ass'y [77] so that its recess is engaged with the
protrusion on the inside of the oil tank chamber of the housing.
4) Assemble the Connecting RodAss'y [38] onto the Crank Shaft [37], rotate the Crank Shaft by hand, and
confirm that the Oil Felt [79] comes into contact with the Seal Lock Hex. Socket Hd. Bolt M8 x 16 [35]
which fixes the Connecting Rod Ass'y [38]. (Fig. 15)
5) After mounting the Felt Holder (C) Ass'y [77], the Oil Felt [79] must be bent toward the Front Cover [7]
side as illustrated in Fig. 15.

--- 15 ---
Fig. 14
Oil Felt [79]
Fig. 15
Recess Protrusion
Oil Tank Chamber Felt Holder (C) Ass'y [77]
Connecting Rod Ass'y [38]
M8 x 16 Hex.
Bolt [35]
Housing
Ass'y Oil Felt [79] Oil Tank Chamber
(5) How to install Seal Ring (A) [44]:
To prevent oil from leaking through between the Housing Ass'y [59] and the Inner Cover [45], Seal Ring (A)
[44] is installed in the Inner Cover [45] for sealing oil. When fitting Seal Ring (A) [44] in the ring groove on the
Inner Cover [45], exercise care not to allow the Seal Ring to twist or project out of the groove.
(6) How to install the L-Ring [9]:
When installing the L-Ring [9] on the Piston [11],
pay attention to the L-Ring direction. The longer
flange side should be directed to the front, as shown
in the figure. (Fig. 16)
(7) Cover Plate [72]:
Any gap between the Cover Plate [72] and the Housing Ass'y [59] may result in oil leakage or failure of
automatic lubrication. Do not disassemble the Cover Plate [72] except when absolutely necessary. When it is
inevitably necessary to disassemble and reassemble the Cover Plate (as when replacing the Oil Felt [79]), for
thorough sealing, apply liquid packing (Fuji Oil Sheet No. 600K) to the mounting surface on the Housing Ass'y
[59].
Fig. 16
Front Cover

--- 16 ---
9-1-3. Screw Locking Agent TB1401
(1) Prior to reassembly, all M5, M6, Hexagon Socket Hd. Bolts and Machine Screws must be coated with Screw
Locking Agent ThreeBond TB1401.
(2) The following parts must be replaced with Hitachi Genuine Parts once they are loosened.
Front Cover Fixing Bolts: M8 x 30 [3]
Cylinder Case Fixing Bolts: M8 x 35 [22]
Fixing Bolt on the Connecting Rod Ass'y [38] M8 x 16 [35]
(CAUTION) If fastening bolts come loose from vibration, it could cause serious damage to the machine.
Ensure without fail that TB1401 Screw Locking Agent is applied as directed above prior to
reassembly.
Before applying the TB1401, carefully clean any grease or other foreign matter from the male
and female threads with gasoline, thinner or similar cleaning solvents.
9-1-4. Tightening Torque
(1) M4 Hexagon Socket Hd. Bolts 4.41 N•m (45 kgf•cm, 39.1 in-Ibs.)
(2) M5 Hexagon Socket Hd. Bolts 7.84 N•m (80 kgf•cm, 69.5 in-Ibs.)
(3) M6 Hexagon Socket Hd. Bolts 9.80 N•m (100 kgf•cm, 86.9 in-Ibs.)
(4) M8 Hexagon Socket Hd. Bolts 29.4 N•m (300 kgf•cm, 260 in-Ibs.)
(5) D4 Tapping Screw 1.96 N•m (20 kgf•cm, 17.4 in-Ibs.)
[NOTE] If above bolts are tightened more than the designated values, it may cause breakage. Without fail,
tighten the Bolts and Screws according to the above specified values.
9-1-5. Internal Wiring
Wiring diagram of products with noise suppressor (Fig. 17)
4.350.49
+1.96
0 +20 0 +12.4 0
+1.96
0 +20 0 +17.4 0
+1.96
0 +20 0 +17.4 0
+4.3
0
0.49
Stator Connector Tube
Switch
Brown
Tube Plug
Blue
Pillar Terminal
Noise
Suppressor
Connector
Stator
Armature
Fig. 17
5

--- 17 ---
Stator
Wiring diagram of products without noise suppressor (Fig. 18)
Stator
Armature
Tube
Tube
Switch
Pillar Terminal
Black
White
Plug
Tube
Fig. 18
9-1-6. Insulation Tests
On completion of disassembly and repair, measure the insulation resistance and dielectric strength.
Insulation resistance: 7 MΩor more with DC 500 V Megohm Tester.
Dielectric strength: AC 4000 V/1 minute, with no abnormalities ••• 220 V --- 240 V
(and 110 V for U.K. products)
AC 2500 V/1 minute, with no abnormalities ••• 110 V --- 127 V
(except U.K. products)
9-1-7. 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.)
110 115 220 230
5.9 5.7 3.0 2.8
240
2.7