Page 1
MODELS DH 25PA DH 25PB POWER TOOLS TECHNICAL DATA HAMMER DRILL DH 25PA, DH 25PB SERVICE MANUAL LIST Nos. DH 25PA: E453 Nov. 1999 DH 25PB: E454 SPECIFICATIONS AND PARTS ARE SUBJECT TO CHANGE FOR IMPROVEMENT...
Page 2
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: Competitors Symbols Utilized Model Name Company Name HR2010 MAKITA...
This series includes the single-mode operation hammer drill Model DH 25PA equipped with a "Rotation + Striking" function, which is based on the Model DH 25PB.
4-1-1. Fast drilling speed The drilling speed is 20% faster than the Model DH 20V as the Models DH 25PA and DH 25PB have great striking energy owing to the optimum design of the rotation speed, striking frequency and the weight of striker. The Models DH 25PA and DH 25PB can drill holes in concrete with a maximum drill bit diameter of 25 mm.
5. SPECIFICATIONS 5-1. Specifications Model DH 25PA DH 25PB Capacity Concrete 3.4 --- 25 mm (1/8" -- - 1") Steel 13 mm (1/2") Wood 32 mm (1-1/4") Power source AC single phase 50 Hz or 60 Hz Voltage (V) Voltage, current and...
5-2. Optional Accessories A. Drilling anchor holes (rotation + striking) Drill bit (slender shaft) (1) Drill bit (slender shaft) (2) Adapter for slender shaft (SDS-plus shank) Drill bit (slender shaft) Adapter for slender shaft Outer dia. (mm) Code No. Code No. Effective length (mm) Overall length (mm) 3.4 (1/8")
Page 9
B. Anchor setting Anchor setting bar to permit anchor setting operation with the hammer drill Anchor setting bar Anchor setting adapter (SDS-plus shank) Part name Part name Code No. Code No. Overall length Overall length 302976 302979 W - 1/4 Anchor setting adapter - A W - 1/4 Anchor setting adapter - B 302975 302978...
Page 10
(2) Guide plate Core bit (outer diameter) (mm) Core bit (outer diameter) Code No. Code No. 32 (1-1/4") 50 (2") 982686 982690 35 (1-3/8") 982687 982691 38 (1-1/2") 982688 982692 45 (1-25/32") 982689 982693 (3) Core bit with guide plate (the guide plate is not required for 25 mm (31/32") and 29 mm (1-5/32") outer diameter core bits.) Outer diameter (mm) Outer diameter (mm)
Page 11
F. Drilling hole (rotation only) ... for drilling holes in steel and wood (DH 25PB only) Chuck adapter (D) Drill chuck (SDS-plus shank) (13VLA) Chuck wrench Part name Code No. Chuck adapter (D) (for SDS-plus shank type) 303624 13 mm (1/2") Drill chuck 13VLA (with chuck wrench) 950272 --- 8 ---...
Page 12
G. Driving screws (rotation only) (DH 25PB only) Chuck adapter (D) Drill chuck (SDS-plus shank) (13VLA) Chuck wrench (1) Cross-recessed head (Phillips) bit (2) Slotted-head (minus) bit [Overall length: 70 mm] [Overall length: 50 mm] (For use with cross-recessed head (Phillips) screw) (For use with slotted-head (minus) screw) Tip thickness Stamped bit No.
Page 13
I. Grease for electric impact drill Containing 500 g (17.64 oz): Code No. 980927 Containing 30 g (1.06 oz): Code No. 981840 70 g (2.5 oz): Code No. 308471 J. Dust cup, dust collector (B) Dust collector (B) ass'y Code No. 306885 --- 10 ---...
Drilling speed depends on the operating conditions. The test results shown in Fig. 1 are based on actual tests at the factory and should be used as a reference only. The drill bits which used in the test are the Hitachi genuine SDS-plus shank bits. Pressing force: 98 N (10 kgf)
7. PRECAUTIONS IN SALES PROMOTION In the interest of promoting the safest and most efficient use of the Models DH 25PA/PB Hammer Drills by all of our customers, it is very important that at the time of sales 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.
The gear change section (in the Gear Cover) uses Hitachi Motor Grease No. 29 for power tools. Supply with 60 g of this grease. Do not use the special grease used for the hammering section, or it will leak into the motor parts and result in a failure of the tool.
Fig. 2 Transmission of rotation Transmission of rotation is described with reference to Fig. 2. The gear arrangement of the Models DH 25PA and DH 25PB is the same as that of Model DH 20V. Rotation of the armature is transmitted to the second gear to rotate the third gear via the slip mechanism between the second gear and the third pinion shaft.
Page 19
A clutch plate holding a steel ball is inserted between the second gear and the spring plate as a slip mechanism in the Models DH 25PA and DH 25PB. If an excessively large torque is applied to the tool shaft, the second gear idles and does not transmit rotation.
Speed control The Models DH 25PA and DH 25PB are equipped with a variable speed control switch which permits free Adjustment of the rotation speed and striking force. When drilling fragile materials, pull the switch trigger gently for low rotation speed (striking force) to achieve optimum results.
8-6. Drill Bits The chuck section is designed exclusively for the popular and widely available SDS-plus shank bits, as shown in Fig. 4. Rotating torque is transmitted to the drill bit by two key rails provided in the tool holding section. A steel ball is used to prevent the bit from coming off.
8-8. Dust Collector (B) While drilling holes overhead, dust collector (B) can be mounted on the Models DH 25PA/PB to prevent dust and chips from falling downward. Dust collector (B) is intended solely for use when drilling holes in concrete, and cannot be used for drilling holes in steel or wood.
Page 23
Approx. 72 mm (2-27/32") Approx. 16 mm (5/8") Grip (on the main body side) Drill bit length: 166 mm Drill bit length: 110 mm Socket adapter (B) Socket Seal cover Dust cover Retaining ring for D30 shaft Outer race Washer D6.35 Steel ball Fig.
The [Bold] numbers in the descriptions below correspond to the item numbers in the Parts List and exploded assembly diagram for DH 25PA and the <Bold> numbers to those in the Parts List and exploded assembly diagram for DH 25PB.
Page 25
(3) Disassembly of the Cylinder Remove the Cylinder Case [31] <31> from the Crank Case [46] <46> and disassemble the retainer section. Remove the Pipe [25] <25>, then the Cylinder [2] <2> from the Cylinder Case [31] <31> by pulling it straight toward the crank case side being careful not to scratch the Oil Seal [21] <21>.
Page 26
Use of Special Repair Tools Snap ring pliers [J-200] (See Fig. 9.) Used to remove the Retaining Ring for D30 Shaft [22] <22> which fixes the Ball Bearing 6906 [23] <23> at the tip end of the Cylinder [2] <2>. Spring hook [J-201] (See Fig.
9-2. Reassembly Perform reassembly in the reverse order of disassembly while observing the given precautions and taking care of the following points. (1) Lubrication Apply special grease to the following portions. Both holes of the Connecting Rod [9] <9> Inside of the Cylinder [2] <2> and the Piston Pin [8] <8> Piston [7] <7>, outer circumference of the Striker [3] <3>...
• (2) Special grease Although the newly developed grease (light yellow) is used in the Models DH 25PA and DH 25PB, the conventional grease for hammer drill (yellow) will be supplied for the time being (Code Nos. 980927, 981840 and 308471). There is no problem even if both greases are used during servicing.
9-4. Wiring Diagrams (1) Products with noise suppressor CR unit Variable switch Stator Black Choke coil Noise suppressor Black Armature Cord Black Choke coil Black Stator Fig. 12 (2) Products without noise suppressor Variable switch Stator Black Armature Cord Black Stator Fig.
9-5. Wiring Work Wiring of variable switch Insert each cord into the terminal 1 and terminal of the variable switch as shown in Fig. 14 and tighten the screw (tightening torque: 0.6 0.2 N • 2 Kgf cm, 5.2 1.7 in lbs.).
9-6. Insulation Tests On completion of reassembly after repair, measure the insulation resistance and conduct the dielectric strength test. Insulation resistance: 7 MΩ or more with DC 500 V Megohm Tester Dielectric strength : AC 4,000 V/1 minute, with no abnormalities 220 V --- 240 V •...
Page 36
DH 25PA STANDARD ACCESSORIES ITEM CODE NO. DESCRIPTION REMARKS USED 971-787 DUST CUP 980-906 STOPPER ROD 980-901 SIDE HANDLE 980-905 ROD HOLDER 980-902 SIDE HANDLE HOLDER 980-904 BAND 980-903 SQUARE BOLT M8 980-939 SIDE HANDLE ASS’Y INCLUD.503-507 318-307 CASE OPTIONAL ACCESSORIES ITEM CODE NO.
Page 37
DH 25PA OPTIONAL ACCESSORIES ITEM CODE NO. DESCRIPTION REMARKS USED 303-608 DRILL BIT (SDS PLUS) D12.7X260 303-594 DRILL BIT (SDS PLUS) D13.0X166 303-595 DRILL BIT (SDS PLUS) D14.0X166 303-596 DRILL BIT (SDS PLUS) D14.3X166 303-609 DRILL BIT (SDS PLUS) D14.3X260 303-597 DRILL BIT (SDS PLUS) D14.5X166...
Page 38
DH 25PA OPTIONAL ACCESSORIES ITEM CODE NO. DESCRIPTION REMARKS USED 950-272 DRILL CHUCK 13VLA INCLUD.680 930-515 CHUCK WRENCH 10G 982-672 CORE BIT (A) 25MM 982-673 CORE BIT (A) 29MM 982-674 CORE BIT (A) 32MM INCLUD.691 982-675 CORE BIT (A) 35MM INCLUD.692...
Page 41
DH 25PB PARTS ITEM CODE NO. DESCRIPTION REMARKS USED 987-203 SEAL LOCK SCREW (W/SP. WASHER) M4X12 992-937 CLUTCH SPRING 992-938 CLUTCH SHAFT 992-506 THRUST WASHER 986-276 STOPPER SPRING 992-925 GEAR COVER 872-470 O-RING (S-26) 600-0DD BALL BEARING 6000DDCMPS2L 360-505C ARMATURE 110V FOR GBR(110V) 360-505E ARMATURE 220V-230V...
Page 42
DH 25PB PARTS ITEM CODE NO. DESCRIPTION REMARKS USED 500-439Z CORD (CORD ARMOR D8.8) FOR AUS 500-391Z CORD (CORD ARMOR D10.1) FOR SUI 500-446Z CORD (CORD ARMOR D10.1) FOR GBR(230V) 500-457Z CORD (CORD ARMOR D8.8) FOR CHN 500-390Z CORD (CORD ARMOR D8.8) FOR HOL 500-454Z CORD (CORD ARMOR D8.8) FOR SAF,GBR(110V)
Page 43
DH 25PB OPTIONAL ACCESSORIES ITEM CODE NO. DESCRIPTION REMARKS USED 303-591 DRILL BIT (SDS PLUS) D12.0X166 303-606 DRILL BIT (SDS PLUS) D12.0X260 303-592 DRILL BIT (SDS PLUS) D12.5X166 303-607 DRILL BIT (SDS PLUS) D12.5X260 303-593 DRILL BIT (SDS PLUS) D12.7X166 303-608 DRILL BIT (SDS PLUS) D12.7X260 303-594...
Page 44
DH 25PB OPTIONAL ACCESSORIES ITEM CODE NO. DESCRIPTION REMARKS USED 971-795 ANCHOR SETTING ADAPTER A W5/16" (MANUAL) 971-796 ANCHOR SETTING ADAPTER A W3/8" (MANUAL) 971-797 ANCHOR SETTING ADAPTER A W1/2" (MANUAL) 971-798 ANCHOR SETTING ADAPTER A W5/8" (MANUAL) 971-799 ANCHOR SETTING ADAPTER B W1/4" (MANUAL) 971-800 ANCHOR SETTING ADAPTER B W5/16"...