Doosan DCT5JS Manual

This manual contains
important safety information
and must be made available to
personnel who operate and
maintain this machine.
DCT5JS MODEL
OPERATION & MAINTENANCE MANUAL
CPN: 85041903_en
DATE: AUGUST 2013
Tool serial number

PORTABLE POWER PRODUCT WARRANTY
2
EN
WARRANTY TOOLS
DOOSAN BENELUX SA warrants to its authorized dealers, who
in turn warrant to the end-user/owner that each new tools will be
free from proven defects in material and workmanship for twelve
(12) months from the date of delivery to the end-user/owner.
Service schedules must be adhered to, documented and genuine
parts/lubricants must be used where applicable. The warranty
does not cover oils and lubricants and latch front head assembly,
springs, seals, dampeners.
During the warranty period, the authorized Doosan Infracore
dealer shall repair or replace, at DOOSAN BENELUX SA option,
without charge for parts and labor of mechanics, any part of the
product which fails because of defects in material or
workmanship. The end user/owner shall provide the authorized
Doosan Infracore dealer with prompt written notice of the defect
and allow reasonable time for replacement or repair. DOOSAN
BENELUX SA may, at its option, request failed parts to be
returned to the factory. Transportation of the product to the
authorized Doosan Infracore dealer for warranty work is the
responsibility of the end user/ owner.
The warranty does not apply to trade accessories not
manufactured by DOOSAN BENELUX SA. The owner shall rely
solely on the warranty, if any, of the respective manufacturers
thereof. The warranty does not cover replacement of scheduled
service items such as oil, filters, tune-up parts, and other high
wear items. The warranty does not cover damages resulting from
abuse, accidents, alterations, air flow obstructions, or failure to
maintain or use the product according to the instructions
applicable to it.
DOOSAN BENELUX SA EXCLUDES OTHER CONDITIONS,
WARRANTIES OR REPRESENTATIONS OF ALL KINDS,
EXPRESSED OR IMPLIED, STATUTORY OR OTHERWISE
(EXCEPT THAT OF TITLE) INCLUDING ALL IMPLIED
WARRANTIES AND CONDITIONS RELATING TO
MERCHANTABILITY, SATISFACTORY QUALITY AND FITNESS
FOR A PARTICULAR PURPOSE.
CORRECTIONS BY DOOSAN BENELUX SA OF
NONCONFORMITIES WHETHER PATENT OR LATENT, IN THE
MANNER AND FOR THE TIME PERIOD PROVIDED ABOVE,
SHALL CONSTITUTE FULFILMENT OF ALL LIABILITIES OF
DOOSAN TRADING LTD FOR SUCH NONCONFORMITIES,
WHETHER BASED ON CONTRACT, WARRANTY, TORT,
NEGLIGENCE, INDEMNITY, STRICT LIABILITY OR
OTHERWISE WITH RESPECT TO OR ARISING OUT OF SUCH
PRODUCT.
THE REMEDIES OF THE END-USER/OWNER SET FORTH
UNDER THE PROVISIONS OF THE WARRANTY OUTLINED
ABOVE ARE EXCLUSIVE AND THE TOTAL LIABILITY OF
DOOSAN BENELUX SA INCLUDING ANY HOLDING,
SUBSIDIARY, ASSOCIATED OR AFFILIATED COMPANY OR
DISTRIBUTOR WITH RESPECT TO THIS SALE OR THE
PRODUCT AND SERVICE FURNISHED HEREUNDER IN
CONNECTION WITH THE PERFORMANCE OR BREACH
THEREOF, OR FROM DELIVERY, INSTALLATION, REPAIR OR
TECHNICAL DIRECTION COVERED BY OR FURNISHED
UNDER THIS SALE, WHETHER BASED ON CONTRACT,
WARRANTY, TORT, NEGLIGENCE, INDEMNITY, STRICT
LIABILITY OR OTHERWISE SHALL NOT EXCEED THE
PURCHASE PRICE OF THE PRODUCT UPON WHICH SUCH
LIABILITY IS BASED.
DOOSAN BENELUX SA INCLUDING ANY HOLDING,
SUBSIDIARY, ASSOCIATED OR AFFILIATED COMPANY AND
DISTRIBUTOR SHALL IN NO EVENT BE LIABLE TO THE END
USER/OWNER, ANY SUCCESSORS IN INTEREST OR ANY
BENEFICIARY OR ASSIGNEE RELATING TO THIS SALE FOR
ANY CONSEQUENTIAL, INCIDENTAL, INDIRECT, SPECIAL OR
PUNITIVE DAMAGES ARISING OUT OF THIS SALE OR BY
ANY BREACH THEREOF, OR ANY DEFECT IN, OR FAILURE
OF, OR MALFUNCTION OF THE PRODUCT UNDER THIS
SALE, WHETHER BASED UPON LOSS OF USE, LOST
PROFITS OR REVENUE, INTEREST, LOST GOODWILL, WORK
STOPPAGE, IMPAIRMENT OF OTHER GOODS, LOSS BY
REASON OF SHUTDOWN OR NON-OPERATION, INCREASED
EXPENSES OF OPERATION OR CLAIMS OF USER OR
CUSTOMERS OF THE USER FOR SERVICE INTERRUPTION
WHETHER OR NOT SUCH LOSS OR DAMAGE IS BASED ON
CONTRACT, WARRANTY, TORT, NEGLIGENCE, INDEMNITY,
STRICT LIABILITY OR OTHERWISE

3
Machine models represented in this manual may be used in various locations world-wide. Machines sold
and shipped into European common market countries requires that the machine display the EC Mark and
conform to various directives. In such cases, the design specification of this machine has been certified as
complying with EC directives. Any modification to any part is absolutely prohibited and would result in the
CE certification and marking being rendered invalid. A declaration of that conformity follows:
DECLARATION OF CONFORMITY WITH EC DIRECTIVES
We
Doosan Benelux SA
Drève Richelle 167
B-1410 Waterloo
Belgium
Declare that under our sole responsibility for manufacture and supply, the product(s)
To which this declaration relates, is (are) in conformity with the provisions of the above directives using the
following principal standards
EN ISO 12100-1, EN ISO 12100-2, EN ISO 5349-2, ISO 8662-3, EN 792
Issued at Waterloo in 1-2010
CONFORMITY TO NOISE DIRECTIVE
2000/14/EC
Doosan Benelux SA declare that the following Hammer Drill has been
manufactured in conformity with the directive as shown.
P. Edgeller
Technical Manager
P. Edgeller
Technical Manager
Directive Model Sound Level dB (A)
Pressure Power
Vibrations Level
m/s2
2000/14/EC
Annex VI Part 1 DCT5JS 109.795.7 9.3 TÜV SÜD
Czech
Nr. 1017
Issued at Waterloo,
5th Declaration 01/2010
Hammer Drill Type DCT5JS
2006/42/CE - 2000/14/CE
EN

SAFETY
4
EN
Look for these signs on machines shipped to markets in North America, which point out potential hazards to the safety of you
and others. Read and understand thoroughly. Heed warnings and follow instructions. If you do not understand, Inform your
supervisor.
Red Background
Indicates the presence of a hazard which WILL cause serious
injury, death or property damage, if ignored.
Orange Background
Indicate the presence of a hazard which CAN cause serious
injury, death or property damage. if ignored.
Yellow Background
Indicates the presence of a hazard which WILL or can cause
injury or property damage. if ignored.
Blue Background
Indicates important set-up, operating or maintenance information.
DCT5JS Hammer Drills are designed for drilling concrete and other demolition work in construction applications.
Doosan Benelux SA is not responsible for customer modifications of tools for applications on which Doosan Benelux SA was not
consulted.
IMPORTANT SAFETY INFORMATION ENCLOSED.
READ THIS MANUAL BEFORE OPERATING TOOL.
IT IS THE RESPONSIBILITY OF THE EMPLOYER TO PLACE THE INFORMATION IN THIS
MANUAL INTO THE HANDS OF THE OPERATOR.
FAILURE TO OBSERVE THE FOLLOWING WARNINGS COULD RESULT IN INJURY.
PLACING TOOL IN SERVICE
• Always operate. inspect and maintain this tool in accordance
with all regulations (local, state, federal and country), that may
apply to hand held / hand operated pneumatic tools.
• For safety, top performance, and maximum durability of parts,
operate this tool at 90 psig (6.2 bar / 620 kPa) maximum air
pressure at the inlet with 1/2" (13 mm) inside diameter air
supply hose.
• Always turn off the air supply and disconnect the air supply
hose before installing, removing or adjusting any accessory on
this tool, or before performing any maintenance on this tool.
• Do not use damaged. frayed or deteriorated air hoses and
fittings.
• Be sure all hoses and fittings are the correct size and are
tightly secured.
• Always use clean, dry lubricated air at 90 psig
(6.2 bar / 620 kPa) maximum air pressure. Dust, corrosive
fumes and/or excessive moisture can ruin the motor of an air
tool.
• Do not lubricate tools with flammable or volatile liquids such as
kerosene, diesel or jet fuel.
• Do not remove any labels. Replace any damaged labels.
USING THE TOOL
• Always wear eye protection when operating or performing
maintenance on this tool.
• Always wear hearing protection when operating this tool.
• Keep hands, loose clothing and long hair away from rotating
end of tool.
• Anticipate and be alert for sudden changes in motion during
start up and operation of any power tool.
• Keep body stance balanced and firm. Do not overreach when
operating this tool.
• Tool accessories may continue to impact briefly after throttle is
released.
• Air powered tools can vibrate in use. Vibration, repetitive
motions or uncomfortable positions may be harmful to your
hands and arms. Stop using any tool if discomfort, tingling
feeling or pain occurs. Seek medical advice before resuming
use.
• Use accessories recommended by Doosan Benelux SA.
• This tool is not designed for working in explosive atmospheres.
• This tool is not insulated against electric shock.
The use of other than genuine Doosan Benelux SA replacement parts may result in safety hazards, decreased tool performance,
and increased maintenance, and may invalidate all warranties.
Repairs should be made only by authorised trained personnel. Consult your nearest Doosan Benelux SA Authorised Service
Centre.
DANGER
WARNING
CAUTION
NOTICE
NOTICE
DANGER
NOTICE

SAFETY
5
EN
WARNING LABEL IDENTIFICATION
FAILURE TO OBSERVE THE FOLLOWING WARNINGS COULD RESULT IN INJURY.
SPECIFIC WARNINGS
• When wearing gloves and operating models with inside trigger,
always be sure that the gloves will not prevent the trigger from
being released.
• Wear safety shoes, hard hat, safety goggles, gloves, dust
mask and any other appropriate protective clothing while
operating the tool.
• Do not indulge in horseplay. Distraction can cause accidents.
• Keep hands and fingers away from the throttle lever until it is
time to operate the tool.
• Never rest the tool or chisel on your foot.
• Never point the tool at anyone.
• Compressed air is dangerous. Never point an air hose at
yourself or co-workers.
• Never blow clothes free of dust with compressed air.
• Be sure all hose connections are tight. A loose hose not only
leaks but can come completely off the tool and while whipping
under pressure, can injure the operator and others in the area.
Attach safety cables to all hoses to prevent injury in case a
hose is accidentally broken.
• Never disconnect a pressurised air hose. Always turn off the
air supply and bleed the tool before disconnecting a hose.
• The operator must keep limbs and body clear of the chisel. If a
chisel breaks, the tool with the broken chisel projecting from
the tool will suddenly surge forward.
• Do not ride the tool with one leg over the handle. Injury can
result if the chisel breaks while riding the tool.
• Know what is underneath the material being worked. Be alert
for hidden water, gas, sewer, telephone or electric lines.
• Use only proper cleaning solvents to clean parts. Use only
cleaning solvents which meet current safety and health
standards. Use cleaning solvents in a well ventilated area.
• Do not flush the tool or clean any parts with diesel fuel. Diesel
fuel residue will ignite in the tool when the tool is operated.,
causing damage to internal parts. When using models with
outside triggers or throttle levers, take care when setting the
tool down to prevent accidental operation.
• Do not operate the tool with broken or damaged parts.
• Never start the tool when it is lying on the ground.
• This tool is not designed for working in explosive atmospheres.
• This tool is not insulated against electric shock.
WARNING
Always wear eye protection
when operating or performing
maintenance on this tool.
WARNING
WARNING
Always wear hearing
protection when operating
this tool.
WARNING
WARNING
WARNING WARNING
WARNING
Always turn off the air supply
and disconnect the air supply
hose before installing,
removing or adjusting any
accessory on this tool, or
before performing any
maintenance on this tool.
OFF
ON
Air powered tools can vibrate
in use. Vibration, repetative
motions or uncomfortable
positions may be harmful to
your hands and arms. Stop
using any tool if discomfort,
tingling feeling or pain occurs.
Seek medical advice before
resuming use.
WARNING
Keep body stance balanced
and firm. Do not overreach
when operating this tool.
WARNING
WARNING
WARNING
Do not carry the tool by the
hose.
WARNING
WARNING
Do not use damaged, frayed
or deteriorated air hoses and
fittings.
WARNING
WARNING
Operate at 90 psig
(6.2 bar / 620 kPa)
Maximum air pressure.
90 psig
(6.2 bar / 620 kPa)

PLACING TOOL IN SERVICE
6
EN
LUBRICATION
Use a high quality Rock Drill Oil with a flash point between 370
and 450 degrees Fahrenheit (188 and 232 degrees Celsius).
Proper lubrication is the most important single factor
responsible for the service life of the Hammer Drill. A Hammer
Drill can be severely damaged during the first few minutes of
operation if not properly lubricated, it is therefore
recommended to put 2 to 3cm³ of oil into the drill's hose.
Periodically connection before startup.the entire tool should be
disassembled, the parts should be washed in a clean,
nontoxic, nonflammable, commercial solvent, dried completely
and well oiled before reassembly.
Always use an air line lubricator with this Hammer Drill. A
Doosan Air Line Lubricator (CPN 35371111) is recommended
for proper lubrication. Install it in the main air supply line within
1.5 meters (5 ft.) of the Hammer Drill.
The oil level in the air line lubricator should be checked at the
beginning of each eight hour shift and once during the shift.
Every effort must be made to avoid oil contamination from dirt
or other impurities. Oil should be kept in covered containers
and stored. if possible, in an area that is relatively dust free.
Before filling the air line lubricator, the area around the filler
plug should be wiped clean.
The oil used in the lubricator must be a well refined petroleum
lubricating oil. It must be suitably compounded to provide the
specified consistency and film strength, and be further
compounded to provide the specified steam emulsion number.
The latter is required to provide a satisfactory lubricant for
such Hammer Drills where water or wet air is encountered.
The oil must also be substantially non-corrosive to steel and
bronze, and contain little or no sulphur.
The composition of the “film strength” additive is not specified.
The additive must be suitable for use with both steel and
bronze, and be substantially non-corrosive to both metals.
Except for consistency, all tests must be conducted in
accordance with the standard method (latest edition) of the
American Society for Testing Metals.
Characteristics Method
Below 20°F
(-6.7 °C)
Light
20 to 90°F
(-6.7 to 32.2 °C)
Medium
Above 90°F
(32.2 °C)
Heavy
Viscosity:
SUS at 100°F (37.8°C)
SUS at 210°F (98.9°C)
ASTM-D2161
ASTM-D2161
175 Min.
46
450 Min.
65
750 Min.
85
cSt at 40°C ASTM-D445 37 Min. 105 Min. 160 Min.
cSt at 100°C ASTM-D445 6 11 16
Flash Point, °F (°C) Min ASTM-D92 370 (188) 400 (204) 450 (232)
Pour Point, °F (°C) Max ASTM-D97 -10 (-23) -10 (-23) 0 (-18)
Viscosity Index, Min ASTM-D2270 90 90 90
Steam Emulsion No., Min ASTM-1935-65 1200 1200 1200
Consistency - Stringy Stringy Stringy
Falex Load Test, Ibs. (Min.) ASTM-D2670 2000 2000 2000
Timken, E. P. Test lbs. (Min.) ASTM-D2782 30 30 30

PLACING TOOL IN SERVICE
EN
7
OPERATION
Before starting the Hammer Drill, make certain the Assembly
Rod Nuts are tight 8Nm (6Ibs.ft.). If the tool is new, check and
tighten the Nuts after one or two hours of operation. Running
the tool with loose Assembly Rods will cause rapid wear and
breakage of parts.
Almost immediately after starting the Hammer Drill, check for
presence of oil at the exhaust ports and on the drill steel
shank. This is the only assurance that oil is travelling all the
way through the Hammer Drill. Break in a new Hammer Drill
slowly, usually half throttle for at least 30 minutes. Heating is
not unusual in a new Hammer Drill and it should be checked
carefully during the first few hours of operation. In most cases,
heating will be localized around the front end of the cylinder.
Test this area frequently with the hand. As long as the hand
can be held on the part comfortably, it is safe to continue
drilling. When the heat is great enough to cause discomfort,
stop the Hammer Drill and let it cool. Since lack of oil can
cause excessive heating, check again to see that the steel
shank is oily.
Collaring the Hole
1. When starting the bole hold the Hammer Drill firmly
against the work and use a steel short enough so that the
Hammer Drill can be handled comfortably.
2. Open the throttle gradually and drill at half throttle or less.
3. The Hammer Drill should be kept at right angles to the
work until the hole is collared, then repositioned for angled
drilling.
Drilling the Hole
1. Hold the Hammer Drill with both hands, spread feet apart,
and apply a firm steady pressure.
Spread legs and feet clear of the drill steel to prevent
injury if a steel breaks. When a steel breaks, the Hammer
Drill, with a piece of broken steel projecting from the
fronthead, drops to the ground suddenly.
2. Hold the Hammer Drill against the work to get maximum
efficiency from the tool. Failure to do this can result in an
excessive heat buildup at the front end of the Cylinder
which can damage the steel holder. Never back the steel
out of the hole at full throttle.
3. The correct amount of pressure for maximum drilling
efficiency can be gained only through experience, but
generally, the correct pressure is usually recognizable by
the rhythmic sound of the exhaust and the free rotation of
the steel.
4. Insufficient pressure will cause the Hammer Drill to
bounce and may crack carbide inserts.
5. Too much pressure will slow down the Hammer Drill and
may result in a stuck steel.
6. Keep the Hammer Drill, steel, and hole aligned at all
times. Hold the Hammer Drill with both hands.
Excess pressure on one side throws the Hammer Drill out
of alignment. Misalignment causes a drag on the rotation
parts which impairs drilling efficiency by reducing the
drilling speed and force of the blow. Misalignment will
also cause unnecessary chuck wear, and will soon cause
spalling of the piston and chipping or premature breakage
of the drill steel.
Cleaning the Hole
Always keep the hole clean and free of cuttings by "blowing"
the hole frequently. The bit must work on fresh material. If the
bit churns in its own cuttings, drilling speed is reduced, and the
possibility of the steel becoming stuck is increased.
Stuck Steel
When drilling moist formations there is often a tendency for
cuttings to pack in the hole immediately behind the bit forming
a "mud collar", Through action of the rotating bit, wet cuttings
pack solidly against the wall of the hole; the condition can
become aggravated and cause a stuck steel.
To remove a stuck steel:
1. Remove the Hammer Drill and make an attempt to loosen
the steel with a wrench.
2. Do not try to pull a stuck steel with the Hammer Drill.
Heavy thrust loads can damage front end parts or loosen
the bit from the steel.
To prevent a stuck steel:
1. Blow the hole often.
2. Keep the bit working against fresh material.
Suggestions for Drillers
1. Never pound on a stuck steel. Nothing is accomplished,
and the drill and bit may be permanently damaged in the
process.
2. Never retract the Hammer Drill at full throttle.
3. Never strike the Hammer Drill with tools. The cylinder or
other part may become dented or damaged.
4. Never try to repair the Hammer Drill on the job. Take it to a
repair shop.
5. Never drag a Hammer Drill along the ground as the
exhaust port and other openings will scoop up dirt.
6. Always clear the air supply line before attaching it to the
Hammer Drill. Purging the line will prevent moisture, pipe
scale and other foreign matter from being carried into the
Hammer Drill with the air.
7. Always be sure the Hammer Drill is well lubricated. Adjust
the line oiler so that the shank of the steel always shows
an oil film but does not cause fogging.
8. Always keep the assembly rods tight and at an equal
tension.
9. Always keep the Hammer Drill aligned with the drill steel
and hole.
WARNING
CAUTION

PLACING TOOL IN SERVICE
8
EN
Care and Use of Bits
1. Be certain the bit fits on the taper of the steel.
2. Never approach the material with the Hammer Drill
running. Position the Hammer Drill carefully and collar the
hole at reduced throttle. This prevents damage to bit
inserts.
3. Always keep the Hammer Drill fed up to the work.
Insufficient feed pressure will cause the bit to become
loose on the steel and will cause inserts to tear loose.
4. Always maintain alignment between the Hammer Drill and
the hole.
5. Never allow the hole to become filled with loose cuttings.
Blow the hole frequently.
6. Never retract the Hammer Drill at full throttle, use part
throttle.
7. Never force or broach the bit into a hole.
8. Don't rough handle steels with bits on.
9. Never run a dull bit.
10. Remove the bit by pulling it from the steel.
Never clamp the bit in vice jaws. The squeeze caused by
clamping will only tighten the bit on the steel.

MAINTENANCE
EN
9
1

MAINTENANCE
10
EN
†Not illustrated.
•Indicates Tune-up Kit part.
CPN
Grip Handle Assembly
1 Grip Handle 03764909
2 Throttle Lever 03764917
3•Throttle Lever Pin 03764230
5•Throttle Valve Pin 03764289
6•Throttle Valve Stem 03764263
7•Throttle Valve Face 03764271
8 Throttle Valve Stem Bushing 03764248
9•Throttle Valve Spring 03764297
10 Inlet Bushing Assembly 03771458
10A •Inlet Bushing Seal 03768843
11 Valve SeaL 03765013
12 •Valve Pin (2) 03765021
13 •Valve 03764537
14 Valve Cap 03765047
15 Cylinder 03765062
16 Piston 03765054
17 Chuck Sleeve 03765Il2
18 Ratchet Gear 03765070
19 •Ratchet Key (2) 03765088
20 •Ratchet Key Pin (2) 03765096
21 •Ratchet Key Pin Spring (2) 03765104
22 Nozzle 03765120
23 Barrel. 03765153
24 Assembly Rod (2) 03765005
25 Assembly Rod Spring (2) 03765138
26 Assembly Rod Nut (2) 03765146
27 Retainer 03764339
† Nameplate 22113013

MAINTENANCE
EN
11
Always wear eye protection when operating or performing
maintenance on this tool. Always turn off the air supply
and disconnect the air supply hose before installing,
removing or adjusting any accessory on this tool or
before performing any maintenance on this tool.
LUBRICATION
Use only a high quality Rock Drill Oil with a flash point
between 370°F and 450°F (188°C and 232°C) and lubricate
as instructed in the section Placing the Tool in Service.
DISASSEMBLY
General Instructions
1. Do not disassemble the tool any further than necessary to
replace or repair damaged parts.
2. When grasping a tool or part in a vice, always use leather-
covered or copper-covered vice jaws to protect the
surface of the part and help prevent distortion. This is
particularly true of threaded members and housings.
3. Do not remove any part which is a press fit in or on a
subassembly unless the removal of that part is necessary
for repairs or replacement.
4. Do not disassemble the tool unless you have a complete
set of new gaskets and O-rings for replacement.
5. Never attempt extensive maintenance or major repairs in
the field; always send the Hammer Drill to the repair shop.
6. Clean the exterior of the Hammer Drill before
disassembly.
7. Provide a clean work area for disassembling the Hammer
Drill.
8. Use a lead or babbitt hammer, if necessary, to loosen
exterior parts. Use a brass rod or soft drift. for removing
interior parts.
9. Handle all parts carefully. Hardened parts may chip or
break if dropped on a hard surface.
10. Probe all parting to loosen and clean out all foreign
matter. Place small parts in a clean box to prevent loss.
Disassembly of the Hammer Drill
In the following step, do not exert extreme pressure on
the Handle. The Handle can be cracked if the vice is
tightened excessively.
1. Grasp the Handle (1) firmly in leather covered or copper
covered vice jaws with the Barrel (23) upward.
2. Remove the two Assembly Rod Nuts (26) and Assembly
Rod Springs (25).
When separating the front end from the Housing in the
next step, the Piston (16) is free to drop out of the
Cylinder. Do not allow it to fall on a hard surface.
3. Grasping the Cylinder (15), carefully lift the assembled
front end from the Handle.
4. Lift the Valve Cap (14), Valve (13) and Valve Seat (11)
from the Handle and remove the Handle from the vice.
5. If the Valve Pins (12) require replacement, press the two
Valve Pins from the Valve Cap.
6. Remove the two Assembly Rods (24) from the Handle.
7. Separate the Cylinder from the Barrel (23). If the Piston
remained in the Cylinder, remove it.
8. Using needle nose pliers, pull the two Ratchet Keys (19)
from the Barrel.
9. Slide the Ratchet Gear (18) out of the Barrel.
10. Using needle nose pliers, remove the two Ratchet Key Pin
Springs (21) and the two Ratchet Key Pins (20) from the
recesses in the inner wall of the Barrel.
11. Slide the Chuck Sleeve (17) and Nozzle (22) out of the
Barrel.
12. Using a wrench, remove the Inlet Bushing Assembly (10)
from the Handle. Remove the Inlet Bushing Seal (10A)
from the Bushing.
13. Remove the Throttle Valve Spring (9), Throttle Valve Pin
(5), Throttle Valve Face (7) and the Throttle Valve Stem
(6).
14. If the Throttle Valve Stem Bushing (8) requires
replacement, press the Throttle Lever Pin (3) from the
Handle and remove the Throttle Lever (2). Using an arbor
press and a rod that fits into the throttle lever slot, press
the Bushing out of the Handle through the Inlet Bushing
opening.
ASSEMBLY
General Instructions
1 When grasping a tool or part in a vice, always use leather
covered or copper covered vice jaws to protect the
surface of the part and help prevent distortion. This is
particularly true of threaded members and housings.
2 Clean, and coat each part with a thin film of oil before
assembly.
3 Apply a film of O-ring lubricant to all O-rings before final
assembly.
4 Except for press fits, parts should fit together easily. If
force is required to assemble parts, the parts are out of
alignment and must be correctly aligned to prevent
binding and damage.
WARNING
CAUTION
CAUTION

MAINTENANCE
12
EN
Assembly of the Hammer Drill
1 If the Throttle Valve Stem Bushing (8) was removed, press
a new Bushing into the Handle (1).
2 Position the Throttle Lever (2) in the Handle and secure it
by pressing the Throttle Lever Pin (3) into the Handle and
through the Throttle Lever.
3 Insert the Throttle Valve Stem (6) into the Throttle Valve
Stem Bushing.
4 Position the slotted end of the Throttle Valve Face (7)
against the Throttle Valve Pin.
5 Install the smaller diameter end of the Throttle Valve
Spring (9) on the short hub of the Throttle Valve Pin (5).
Using the Spring to hold the Pin, install the long end of the
Throttle Valve Pin into the Throttle Valve Face.
6 Install the Inlet Bushing Seal (10A) on the Inlet Bushing
(10).
7 Thread the Inlet Bushing Assembly into the Handle and
tighten it to 12 Nm (9 lbs.ft.) torque.
8 Grip the front end of the Barrel (23) very lightly in leather
covered or copper covered vice jaws with the bit end
downward.
9. Insert the Nozzle (22) into the Barrel from the handle end
of the Barrel.
10. Insert the Chuck Sleeve (17) into the Barrel, making
certain the two hubs on the leading end of the Sleeve
mesh with the recesses in the end of the Nozzle.
11. Using needle nose pliers, insert one of the Ratchet Key
Pin Springs (21) into the hole in the inner wall of the
Barrel.
12. Position the small diameter end of the Ratchet Key Pin
(20) inside the Spring.
13. While compressing the Spring with the Pin, insert the
Ratchet Key (19), flat end first, into the lengthwise groove
in the Barrel. Slide the Key to the end of the groove
capturing the Spring and Pin between the Ratchet Key
and the wall of the Barrel.
14. Repeat steps 11, 12 and 13 on the opposite side of the
Barrel.
15. Push both Ratchet Keys toward the wall of the Barrel and
install the Ratchet Gear (18) in the Barrel.
16. Insert the Piston (16) into the Cylinder (15).
17. While grasping the protruding shaft of the Piston and
supporting the Cylinder, engage the two spiral grooves of
the Piston with the internal teeth of the Ratchet Gear.
18. Reach into the front end of the Barrel and apply firmer
pressure against the Nozzle to prevent it from rotating. At
the same time, rotate the Piston and Ratchet Gear until
the two straight grooves of the Piston engage the internal
teeth of the Nozzle or Chuck Sleeve. When properly
oriented, the Piston and Cylinder will move forward until
the Cylinder butts against the Barrel.
19. If the Valve Pins (12) were removed at disassembly, press
the two Valve Pins into the Valve Seat (11) until they stop
against the bottom of the hole. There are five holes in the
bottom half of the Valve Seat. Press the Pins, one on each
side, into the two holes in the lower half of the Valve Seat
nearest the Assembly Rod clearance grooves.
20. Install the Valve (13) in the counterbore of the Valve Seat.
21. Align the holes in the Valve Cap (14) with the holes in the
Valve and, with the hub end trailing, slide the Valve Cap
onto the Valve Pins and against the Valve and Valve Seat.
22. Position the Valve Cap, Valve Seat and Valve against the
rear of the Cylinder.
23. Position the assembled Handle (1) against the Valve Seat
and slide Assembly Rods through the Handle and the
Barrel adjusting all parts requiring alignment.
24. Grasping the Barrel, and with pressure against the
Assembly Rods, carefully remove the tool from the vice
and stand the tool upright on its Handle on a workbench.
25. Install the Assembly Rod Springs (25) and Assembly Rod
Nuts (26) on the Assembly Rods. Tighten the Nuts evenly
to 8Nm (6Ibs.ft.) torque.

FAULT FINDING
EN
13
FAULT FINDING GUIDE
Fault Probable Cause Solution
Hammer Drill will not start Plugged exhaust ports Dismantle the Hammer Drill and clean out all ports and
air passages.
Valve Seat is stuck due to gummy oil Remove the assembled valve and Valve Seat and
clean the parts. Never use dirty oil or oil that does not
conform to the recommended specifications.
Frozen piston due to improper
lubrication
Disassemble the Hammer Drill and remove the Piston.
Repair the piston by placing in a high speed lathe and
dressing it with fine emery cloth. Never run the
Hammer Drill without the proper lubricating oil in the
lubricator.
Assembly Rods tightened unevenly
causing binding
Check the Hammer Drill for correct assembly and
tighten the Assembly Rod Nuts evenly to 8Nm
(6Ibs.ft).
Hammer Drill loses power
rapidly
Restriction in air supply line Remove all kinks or sharp bends in the air supply line.
Air hose is too long Keep the air supply hose as short as possible - under
15 m (50 ft).
Air hose diameter too small Use a 13 mm (1/2") inside diameter air supply hose.
Hammer Drill lacks power Low air supply pressure The air supply pressure at the tool should be 6,2 bar
(90 psig).
Running on Fronthead cushion Maintain a constant pressure on the Hammer drill.
Keep the steel against the work.
Plugged air passages Disassemble and clean out all ports and air passages.
Lack of lubricating oil The Hammer Drill is getting adequate lubrication when
a thin film of oil can be detected on the shank end of
the steel. Check the Lubricator and refill if necessary
Short drill steel shank due to wear or
regrinding
Install a new drill steel.
Plugged Inlet Bushing Assembly Clean the screen in the Inlet Bushing Assembly.
Drill steel does not rotate;
rotation is weak
Steel is binding in hole Apply correct amount of down pressure to the
Hammer Drill. Keep the Hammer Drill, drill steel and
hole in alignment. Replace worn bits.
Worn rotation parts - Piston, Ratchet
Gear, Ratchet Key, etc.
Replace the worn parts with new parts.
New Hammer Drill overheats New Hammer Drill may overheat at the
front end of the Cylinder
Run the new Hammer Drill at less than full throttle until
it is broken in. Adjust the Lubricator to provide an
adequate supply of oil.

FAULT FINDING
14
EN
SAVE THESE INSTRUCTIONS
DO NOT DESTROY
FAULT FINDING GUIDE
Fault Probable Cause Solution
Tool overheating after break-in
period
Running on Fronthead cushion Apply sufficient down pressure on the Hammer Drill to
keep the bit feeding into the rock.
Piston not hitting shank because shank
is short
Install a new drill steel.
Pulling steel at full throttle Use as little throttle as possible when pulling steels to
avoid running on the fronthead cushion.
Lack of lubrication or improper
lubricating oil
If the Hammer Drill is receiving adequate lubrication, a
thin film of oil will be detected on the steel shank.
Check the oil level in the Lubricator and refill if
necessary.
Slow drilling speed Dull bit Replace the drill bit.
Cuttings not being removed from hole Blow air frequently to keep bit working on fresh
material.
Hammer Drill and steel are DOL aligned
with the hole. Steel or bit is binding
Check alignment while drilling to prevent binding.
Erratic or sluggish operation Lubricating oil too heavy, slowing down
valve action
Use only the recommended lubricating oil.
Gummed oil or dirt in operating parts Disassemble the tool and clean out dirt and gummy
residue. Service the Hammer Drill with clean oil.
Protect the tool from dirt when idle.
Dirty Inlet Bushing Assembly Clean the screen in the Inlet Bushing Assembly.
Drill steel is stuck Driving steel after it is dull or has lost its
gauge
Do not force a dull bit. Sharpen the bit or replace it
with a new bit.
Cuttings are not being blown from the
hole
Blow holes frequently to keep the hole clear of
cuttings.
Steel is misaligned with hole causing
binding
Keep Hammer Drill, steel and hole in alignment at all
times.
Chipping or breakage of Piston Drill steel shank is too hard or rounded
on the end, causing minimum contact
with the striking face of the Piston
Replace the drill steel. One bad drill steel shank can
ruin many Pistons.
Heat cracking due to faulty lubrication Keep the Hammer Drill well lubricated with proper type
of oil.
Assembly Rod breakage Uneven tension on Assembly Rods or
loose Assembly Rods
Keep the Assembly Rod Nuts Light and at an even
torque. Tighten Assembly Rod Nuts alternately.
Freezing at exhaust ports Excessive moisture in the air supply
line (Usually occurs in low ambient
temperatures)
Install moisture traps in the air supply line or add anti-
freeze lubricant.
Fogging Excessive moisture in the air supply
line
Clean out the air lines. If moisture traps are installed in
the air supply line. drain the moisture.
Excessive lubrication Adjust the lubricator for the proper rate of lubricant
feed.
NOTICE

GENERAL DATA
EN
15
SPECIFICATIONS FOR DCT5JS HAMMER DRILL
Model DCT5JS
Chuck Size 19 hex x 50
Cpn 01338524
Overall Length mm (in) 408 (16)
Overall Width mm (in) 85 (3.35)
Weight Kg (lbs) 5 (11)
Max Working Pressure Bar (psi) 6,2 (90)
Air Consumption M3/min (CFM) @ 6 Bar 0,48 (17)
Certified Vibration Level M/s2@ 6 bar 9.3
Certified noise Level LWA 109.7
Impact Frequency / min 2650
Rotation (RPM) 300
Assembly Rod Nut Torque Nm (lbs.ft) 8,0 (6.0)
Air inlet Connector Torque Nm (Ibs.ft) 12 (9)

Doosan Benelux SA
Drève Richelle 167
B-1410 Waterloo, Belgium
www.doosanportablepower.com