Hitachi WH 14DM Manual

TECHNICAL DATA
AND
SERVICE MANUAL
CORDLESS IMPACT DRIVER
WH 14DM
SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT
LIST No. F884 Jun. 2003
W
MODEL
WH 14DM
Hitachi 
Power Tools

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:
Symbol Utilized Competitor
Company Name Model Name
DEWALT DW054
P
MAKITA BTD/50SA
C

Page
1. PRODUCT NAME.............................................................................................................................. 1
2. MARKETING OBJECTIVE ................................................................................................................ 1
3. APPLICATIONS................................................................................................................................. 1
4. STANDARD EQUIPMENT ................................................................................................................. 1
5. SELLING POINTS ............................................................................................................................. 2
5-1. Selling Point Descriptions ...................................................................................................................3
6. SPECIFICATIONS ............................................................................................................................. 5
6-1. Specifications......................................................................................................................................5
6-2. Optional Accessories ..........................................................................................................................6
7. COMPARISONS WITH SIMILAR PRODUCTS ................................................................................. 7
7-1. Specification Comparisons .................................................................................................................7
7-2. Tightening Torque ...............................................................................................................................8
7-3. Number of Screws Driven.................................................................................................................10
8. PRECAUTIONS IN SALES PROMOTION .......................................................................................11
8-1. Safety Instructions ............................................................................................................................11
8-2. Tightening Torque Inspection prior to Operation ...............................................................................13
8-3. Tightening Torque Variation ..............................................................................................................13
8-4. Suggestions and Precautions for the Efficient Use of the Charger...................................................14
9. OTHER PRECAUTIONS ................................................................................................................. 14
10. REPAIR GUIDE ............................................................................................................................. 15
10-1. Precautions in Disassembly and Reassembly................................................................................15
10-2. Precautions in Disassembly and Reassembly of Battery Charger .................................................22
11. STANDARD REPAIR TIME (UNIT) SCHEDULES......................................................................... 23
Assembly Diagram for WH 14DM
CONTENTS

--- 1 ---
1. PRODUCT NAME
Hitachi Cordless Impact Driver, Model WH 14DM
2. MARKETING OBJECTIVE
Owing to the shift of demand from nails to screws and increased demand for long screws, there is a market need
for a powerful, high-speed, compact and easy-to-handle impact driver that provides more efficient operation per
charge. The current cordless impact drivers Model WH 9DM (9.6 V) and WH 12DM (12 V) are well reputed on the
market. The new Model WH 14DM (14.4 V "Super Impact 14") is being introduced to respond to user requests for
a more powerful impact driver with high torque.
•30% higher speed than Model WH 12DM •Higher torque 135 N•m (1375 kgf•cm, 1190 in-lbs.)
•Higher durability •Comfortable handle grip
The Model WH 14DM broadens our lineup of cordless impact drivers from 9.6 V to 14.4 V.
3. APPLICATIONS
•Tightening/loosening of small screws, tapping screws, wood screws, bolts, nuts, etc.
•Drilling into wood and various other materials (with use of optional accessory drill chuck adapter).
[Applicable Markets]
•Wood-product assembly: Tightening/loosening of wood screws.
•Construction industry: Assembly of scaffolding, roofing, aluminum sashes, fencing, etc.; removal of plastic cones
from concrete forms, mounting/removal of form ties; drilling into the wood frames of concrete forms, etc.
•Manufacturing industry: Assembly work for automobiles, rolling stock, shipbuilding, agricultural machinery and
tools, industrial machines, steel furniture, etc.
•Utility industry: Assembly and installation of electric equipment, plumbing facilities, air conditioning (duct
assembly, etc.), sanitary fixtures and various other facilities.
•Service industry: General repair work; installation of advertising aids, automobile repair, assembly of garages
and carports storage sheds, etc.
•Various other assembly, construction or repair facilities.
4. STANDARD EQUIPMENT
(1) BFK specification: One EB 14B battery (NiCad, capacity 2.0 Ah), UC 14YF2 charger and case
(2) 2BFK specification: Two EB 14B batteries (NiCad, capacity 2.0 Ah), UC 14YF2 charger and case
(3) HFK specification: One EB 1430H battery (NiMH, capacity 3.0 Ah), UC 14YF2 charger and case
(4) 2HFK specification: Two EB 1430H batteries (NiMH, capacity 3.0 Ah), UC 14YF2 charger and case

--- 2 ---
5. SELLING POINTS
Model WH 14DM Cordless Impact Driver
Ultra-compact body but class-top tightening speed
(30% faster than the Model WH 12DM, same as P, and
30% faster than C)
Maximum tightening torque 135 N•m (1375 kgf•cm,
1190 in-lbs.), the same torque in forward/reverse rotation
Powerful
Selling points common to the Model WH 12DM
• Newly designed compact body
• Ergonomically designed comfortable handle
(slip-resistant double-molded grip)
• High durability, dust resistance and long service life
Compact
• Overall length of the Model WH 14DM
compared with the following models
C: - 11 mm (- 3/64") P: + 12 mm (+ 3/64")
• Height of the Model WH 14DM compared
with the following models
C: - 40 mm (- 1-37/64") P: + 2 mm (+ 5/64")
• Center height of the Model WH 14DM
compared with the following models
C: 0 mm (0") P: - 2 mm (- 5/64")
• Weight of the Model WH 14DM compared
with the following models
C: - 220 g (- 485 lbs.) P: + 100 g (+ 220 lbs.)
Hook with lighting function
• Lighting function is usable at any time.
• Quick slide-out hook (angle-adjustable)
• Mountable on either side
Protector
• Protects workpieces from scratches and stains.
• Resistant to being caught on bracing plates, etc.
• Does not get hot even if operated continuously.

--- 3 ---
5-1. Selling Point Descriptions
Refer to pages 4 through 8 of Technical Data Service Manual for the Models WH 12DM/WR 12DM for common
selling points.
(1) Class-top tightening speed
The Model WH 14DM is equipped with the neo rare-earth magnet motor that has 20 % higher magnetic force
than the previous Model WH 12DM while the armature size is the same and the 15 % larger hammer. With
the computer analysis, the Model WH 14DM gives optimum impact at tightening screws and the tightening
speed is 30 % higher than the previous Model WH 12DM (same as P and 30 % higher than C). The Model
WH 14DM can also tighten long screws at high speed even into a hard wood workpiece. Tightening time
comparison of the Model WH 14DM with C is shown below.
Maximum tightening torque: 135 N•m {1375 kgf•cm, 1190 in-lbs.}
It should be noted that an M12 (15/32") strength grade 12.9 high-strength bolts were tightened in 3 seconds
with a hexagon socket (115 mm (4-3/64") long) in the test. The tightening torque of the Model WH 14DM is
substantially higher than the previous model.
Wood screw 5.3 mm dia. x 120 mm (1/64" x 4-23/32") length, lauan
Wood screw 4.2 mm dia. x 90 mm (11/64" x 3-3/64") length, lauan
* Tightening time may vary depending on hardness of the workpiece, ambient temperature, characteristics
of the battery, etc.
1
2
Test conditions
Bolt: M12 x 45 mm (15/32" x 1-3/4")
(strength grade: 12.9)
Steel plate: Mild steel, thickness: 25 mm (1")
Accessory tool: Hexagon socket
*The data above are intended for reference
purposes only because actual tightening
torque will vary depending on tightening
conditions.
Model Fast Slow
210
8
64 12 14 16 20 sec.
18
HITACHI WH 14DM
P
C
HITACHI WH 12DM
4.0 sec.
4.0 sec. 6.0 sec.
6.5 sec.
Model Fast Slow
2
1345 sec.
HITACHI WH 14DM
P
C
HITACHI WH 12DM
1.8 sec.
1.8 sec.
2.6 sec.
2.6 sec.
140 140
133
109
200
50
100
150
0
2000
(1736 in-lbs)
1500
(1302 in-lbs)
1000
(868 in-lbs)
500
(434 in-lbs)
0
WH 14DM PCWH 12DM
kgf
•
cm N
•
m
Tightening torque
Fig. 1

--- 4 ---
(2) Compact and lightweight
The Model WH 14DM is equipped with a separate-type motor like the Super Impact Series. Thanks to the new
separate-type motor, the steel case is eliminated and the motor section is downsized. In addition, the newly
adopted neo rare-earth magnet motor having 1.2 times higher coercive force is as small as the motor of the
previous Model WH 12DM while it can provide high power. The overall length of the Model WH 14DM is
shortened by 12 mm (3/64") in comparison with P and by 11 mm (3/64") in comparison with C, and it is
equivalent to the previous 12-V product Model WH 12DH thanks to the downsized hammer case. The weight
of the Model WH 14DM is about 220 g (0.485 lbs.) lighter than C (The actual weight of P is about 100 g
(0.220 lbs.) lighter than WH 14DM).
Weight
Catalog weight kg
L Overall length mm
Model
A Center height mm
H Height mm
Actual weight kg
WH 14DM
179 (7-3/64")
27 (1-1/16")
236 (9-19/64")
1.9 (4.1 lbs.)
1.98 (4.4 lbs.)
C
190 (7-31/64")
27 (1-1/16")
276 (10-55/64")
2.1 (4.6 lbs.)
2.20 (4.9 lbs.)
Unit P
167 (6-37/64")
29 (1-9/64")
234 (9-7/32")
1.9 (4.1 lbs.)
1.88 (4.1 lbs.)
(Reference)
WH 12DH
176 (6-59/64")
26 (1-1/32")
245 (9-41/64")
1.7 (3.7 lbs.)
1.73 (3.8 lbs.)
L
H
A

--- 5 ---
6. SPECIFICATIONS
6-1. Specifications
Model Cordless impact driver WH 14DM
Capacity
Item Small screw M4 --- M10 (5/32" --- 3/8")
Ordinary bolt M6 --- M14 (1/4" --- 9/16")
High-strength bolt M6 --- M12 (1/4" --- 15/32")
Tightening torque 135 N•m (1,375 kgf•cm, 1,190 in-lbs.)*1
Tip condition 6.35 mm (1/4") bit holder
Type of motor Fan cooled DC magnet motor
Enclosure Main body: Polyamide resin + elastomer •••••• Housing
Aluminum alloy die casting ••••••••• Hammer case
Elastomer ••••••••••••••••••••••••••••••••• Protector
Storage battery: Polyamide resin (black)
Charger: ABS resin (black)
Type of switch
Trigger switch with forward/reverse changeover pushing button (with brake and variable)
Handle configuration T-type
No-load rotational speed 0 --- 2,600 /min.
Impact rate 0 --- 3,200 /min.
Main body 1.9 kg (4.1 lbs.) (Includes battery)*2
Battery 0.86 kg (1.9 lbs.)
Overall length x height 179 mm (7-3/64") x 236 mm (9-19/64")
Center height 27 mm (1-1/16")
Battery
(Type EB 14B) Sealed cylindrical nickel-cadmium batteries
Nominal voltage: DC 14.4 V
Nominal life: Charging/discharging approximately 1,000 cycles
(in the case of Model UC 14YF2)
Nominal capacity: 2.0 Ah
Battery
(Type EB 1430H) Sealed cylindrical nickel-metal hydride batteries
Nominal voltage: DC 14.4V
Nominal life: Charging/discharging approximately 500 cycles
(in the case of Model UC 14YF2)
Nominal capacity: 3.0 Ah
*1: This torque is based on tightening an M12 (15/32") bolt (strength grade: 12.9) for 3 seconds with a hexagonal socket.
*2: Main body does not include accessory tools (hexagonal bit, etc.).
Charger (UC 14YF2) Sealed power source: Single-phase AC, 50/60 Hz
Voltage: Depending on the order specification
Power input: 44 W
Charging system: Constant current charge with full wave phase control
Overcharge protection system: (1) Battery voltage detection ( 2V system)
(2) Battery surface temperature detection
(thermostat or thermistor)
(3) 120-minute timer
Output voltage: 7.2 V --- 14.4 V
Output current: 1.9 A
Charging time: Approx. 60 minutes (for B-type storage battery at 20 ˚C (68 ˚F))
Approx. 90 minutes (for H-type storage battery at 20 ˚C (68 ˚F))
Product weight: 1.3 kg (2.8 lbs.)
Operable ambient temperature range: 0 ˚C --- 40 ˚C (32˚F --- 104˚F)
The maximum allowable temperature of the EB 14B type battery is 60 ˚C (140˚F) and
the EB 1430HL type battery is 45 ˚C (113˚F).
Weight

--- 6 ---
Prior to charging
During charging
Charging completed
Charging not
possible
High battery
temperature
Blinks
Lit
Blinks
Flickers
Lit
0.5 sec ON, 0.5 sec OFF
Stays ON constantly
0.5 sec ON, 0.5 sec OFF
0.1 sec ON, 0.1 sec OFF
Stays ON constantly
Pilot lamp indications (Model UC 14YF2)
Red pilot lamp
remains lit or flashes.
Green pilot lamp is lit.
Storage battery or charger
is faulty.
Charging not possible
because storage battery
temperature is too high.
6-2. Optional Accessories
(1) Optional accessories for the Model WH 14DM
•Plus driver bit
50 mm (2")
Bit No.
No. 2
No. 3
Code No.
992671
992672
•Hexagon socket
L
B
Stamped figures
9961778 (5/16")65 (2-9/16")8
Stamped figures
5 mm Hexagon socket
Part name L
(mm) B (mm) Code No.
98532910 (3/8")65 (2-9/16")106 mm Hexagon socket
99617812 (15/32")65 (2-9/16")125/16" Hexagon socket 99617913 (1/2")65 (2-9/16")138 mm Hexagon socket
99618014 (9/16")65 (2-9/16")1410 mm Hexagon socket (small type)
99618116 (5/8")65 (2-9/16")1610 mm Hexagon socket 99618217 (21/32")65 (2-9/16")1710 mm Hexagon socket
99619721 (53/64")166 (6-17/32")211/2" Hexagon long socket
•Woodworking drill bit (Code No. 959183)
14 mm dia.
(35/64")
83 mm (3-17/64")
•Drill chuck adaptor set (Code No. 321823)
The drill chuck adapter set permits mounting of various types
of locally-available drill bits for a variety of drilling operations.

--- 7 ---
7. COMPARISONS WITH SIMILAR PRODUCTS
7-1. Specification Comparisons
*1: In the case of tapping screws and wood screws, a minimum of M3 (1/8") is possible.
*2: Max. tightening torque is based on tightening an M12 (15/32") bolt (strength grade: 12.9) for 3 seconds with a hexagon
socket.
*3: Main body weight does not include accessory tools (hexagon bit, etc.).
Maker
Model
Item
Catalog specifications
Capacity
Small screw*1
Ordinary bolt
High-strength bolt
Max. tightening torque N•m
No-load rotation speed min-1
Impact rate min-1
Main body weight kg
Max. tightening torque N•m
Measured figures
No-load rotation speed min-1
Impact rate min-1
Overall length x height mm
Center height mm
Main body weight kg
No-load sound pressure level
dB(A)
Tool tip mounting system
Type of switch
Type of motor
Voltage
Current
Battery
V
A
Type
Nominal capacity Ah
Nominal voltage V
Ambient temperature
˚C
Model
Power input capacity
VA
Recharging voltage
V
Standard accessories
Charger
*3
*2
*3
M 4 --- M 10
(5/32" --- 3/8")
HITACHI
WH 14DM
M 6 --- M 14
(1/4" --- 9/16")
M 6 --- M 12
(1/4" --- 15/32")
135
(1375 kgf•cm, 1190 in-lbs.)
0 --- 2,600
0 --- 3,200
1.9 (4.1 lbs.)
140
(1428 kgf•cm, 1239 in-lbs.)
0 --- 2,650
0 --- 3,210
179 x 236
(7-3/64" x 9-19/64")
27 (1-1/16")
1.98 (4.4 lbs.)
71
Driver chuck
Variable speed
switch with
forward/reverse
changeover lever
DC magnet
14.4
27
EB 14B or EB 1430H
EB 14B: 2.0
EB 1430H: 3.0
14.4
0 --- 40
UC 14YF2
44
7.2 --- 14.4
•Plastic tool case
•Charger (UC 14YF2)
M 4 --- M 10
(5/32" --- 3/8")
M 6 --- M 14
(1/4" --- 9/16")
M 6 --- M 10
(1/4" --- 3/8")
130
(1325 kgf•cm, 1150 in-lbs.)
0 --- 2,300
0 --- 3,000
2.1 (4.6 lbs.)
133
(1356 kgf•cm, 1177 in-lbs.)
0 --- 2,420
0 --- 2,920
190 x 276
(7-31/64" x 10-7/8")
27 (1-1/16")
2.20 (4.9 lbs.)
69
Driver chuck
Variable speed
switch with
forward/reverse
changeover lever
DC magnet
14.4
19
BH 1420 or BH 1433
EB 1420: 2.0
EB 1433: 3.3
14.4
DC 14SA
7.2 --- 14.4
•Plastic tool case
•Charger (DC14SA)
130
(1325 kgf•cm, 1150 in-lbs.)
0 --- 2,400
0 --- 3,000
1.9 (4.1 lbs.)
0 --- 2,560
167 x 234
(6-37/64" x 9-7/32")
29 (1-9/64")
1.88 (4.1 lbs.)
Driver chuck
Variable speed
switch with
forward/reverse
changeover lever
DC magnet
14.4
DW9091
14.4
4.5 --- 40.5
DW9107
7.2 --- 14.4
•Plastic tool case
•Charger (DW9107)
M 4 --- M 8
(5/32" --- 5/16")
HITACHI
WH 12DM
M 5 --- M 12
(3/16" --- 15/32")
M 5 --- M 10
(3/16" --- 3/8")
100
(1020 kgf•cm, 885 in-lbs.)
0 --- 2,300
0 --- 3,000
1.6 (3.5 lbs.)
109
(1112 kgf•cm, 965 in-lbs.)
0 --- 2,390
0 --- 2,800
167 x 226
(6-37/64" x 8-7/8")
26 (1-1/32")
1.66 (3.7 lbs.)
69
Driver chuck
Variable speed
switch with
forward/reverse
changeover lever
DC magnet
12
28
EB 1220BL or EB 1230HL
EB 1220BL: 2.0
EB 1230HL: 3.0
12
0 --- 40
UC 14YF2
44
7.2 --- 14.4
•Plastic tool case
•Charger (UC 14YF2)
PC