DOA HD 13 Guide

HD 13
HYDRAULIC
HAMMER DRILL
SAFETY, OPERATION AND
MAINTENANCE MANUAL
DOA s.r.l.
Via Cortiva 5 – 22060 NOVEDRATE ( Como ITALY
TEL ++39 031 792040 - FAX ++39 031 791917
www .doa .it E-mail: [email protected]
IMPORTANT
READ MANUAL BEFORE USE
KEEP THIS MANUAL FOR
FUTURE CONSULTATIONS
JULY 2013 – 1° edition

CONTENTS OF THE MANUAL
Page
•INTRODUCTION 3
•SAFETY SYMBOLS 4
• DESCRIPTION OF THE PRODUCT
DESCRIPTION 5
TYPICAL APPLICATION 5
ACCESSORIES ON REQUEST 5
TYPICAL POWER SOURCES 5
TECHNICAL CHARACTERISTICS
GENERAL VIEW - MAIN COMPONENTS AND THEIR FUNCTIONS 6
WEIGHT AND DIMENSION 7
PERFORMANCES - SPEED 7
HYDRAULIC CHARACTERISTICS 7
•GENERAL SAFETY NORMS 8
•USE OF THE PRODUCT
WHAT NOT TO DO 10
NEVER USE THE TOOL IF 11
BEFORE WORKING 12
USE OF THE TOOL 13
CUTTING OPERATIONS 14
END OF OPERATIONS 15
•MAINTENANCE AND CARE 13
CLEANING 13
PERIODICAL CONTROL 14
MAINTENANCE OF THE FLEXIBLE HOSES 14
DISPOSAL AND SCRAPPING 15
REPAIR 15
GENERAL INFORMATION ON THE REPAIR 16
DISASSEMBLY 17
•PROBLEM / CAUSE / SOLUTION / CHART 18
•WARRANTY 21
•EXPLODED VIEW AND PART LIST ATTACHED IN SEPARATE SHEET

INTRODUCTION
DEAR CUSTOMER,
CONGRATULATIONS FOR HAVING PURCHASED A DOA PRODUCT. THE TOOL YOU BOUGHT WAS
MANUFACTURED WITH HIGH QUALITY MATERIALS TO ASSURE YOUR MAXIMUM SATISFACTION
AND A LONG LASTING SERVICE WITHOUT PROBLEMS. FOR YOUR SAFETY AND OBTAINING THE
BEST RESULT, WE RECOMMEND TO READ THIS MANUAL AND RESPECT THE SIMPLE
INSTRUCTIONS CONTAINED, THIS WILL PROTECT YOU FROM ACCIDENTS AND AVOID DAMAGES
TO THE EQUIPMENT.
KEEP IT ALWAYS AVAILABLE TOGETHER WITH ITS ENCLOSURES, SO THAT IT CAN BE
CONSULTED WHEN NECESSARY.
IMPORTANT
SOME ENCLOSURES CONTAINING INFORMATION ABOUT ACCESSORY PARTS OR
SAFETY MANUALS OF THE MANUFACTURER OF SUB PARTS OR
SUBCOMPONENTS OF DOA TOOLS, COULD HAVE BEEN SUPPLIED TOGETHER
WITH THIS MANUAL.
THESE ENCLOSURES ARE AN INTEGRAL PART OF THE MANUAL AND THEY MUST
BE KEPT TOGETHER WITH THE MANUAL ITSELF..
BE CAREFUL WHEN YOU CONNECT THE TOOL TO AN HYDRAULIC CIRCUIT WHERE
ARE UNKNOWN HYDRAULIC MAXIMUM VALUES OF PRESSURE AND FLOW. FOR
AVOIDING ACCIDENTS AND DAMAGES TO THE EQUIPMENT, BE SURE THAT THE
MAXIMUM VALUES OF PRESSURE AND FLOW OF THE POWERING CIRCUIT ARE
COMPATIBLE WITH THOSE ONE OF THE TOOL ITSELF.
THE TEXT AND THE ILL
USTRATIONS IN THIS M
ANUAL ARE AN EXCLUSI
VE
PROPERTY OF DOA S.R.L. THE PERSON WHO USES THE TEXT OR
REPRODUCES, EVEN PARTIALLY, ILLUSTRATIONS OR PARAGRAPHS FOR
NON
-
AUTHORISED PURPOSES
CAN BE LEGALLY LIABL
E.

SAFETY SYMBOLS
This manual contains safety warnings represented by symbols
indicating three different levels of danger:
This symbol indicates an operation or situation
extremely dangerous which can cause serious
accidents or death if proper precautions are not
respected
This symbol indicates a dangerous operation or
situation that can cause serious accidents or death
This symbol warns about generic danger that can
cause accidents and damages to the equipment or
the properties.
This symbol indicates important information
WHEN THE EFFECTS OF A CERTAIN ACTION ARE NOT EXACTLY KNOWN, REMIND
THAT EVEN THE SIMPLEST OPERATION MAY HIDE DANGERS.
IN CASE OF DOUBTS DO NOT RISK – DO NOT MAKE EXPERIMENTS!
ASK YOUR DOA DEALER OR YOUR FOREMAN.

GENERAL VIEW – MAIN COMPONENTS AND THEIR FUNCTIONS
1. TRIGGER – is the ON/OFF control of the tool, it has a device that prevents accidental tool starting , it
can be pressed with minimal effort to guarantee operator comfort also in long cutting operations
2. RETURN HOSE – T it is the tube where oil get out/exit the tool and go back to tank
3. OIL PRESSURE HOSE – P it is the tube where oil enter in pressure in the tool
4. SDS MAX QUICK CHUCK STANDARD

HD 13 TECHNICAL CHRACTERISTICS
WEIGHT & DIMENTIONS
WIEGHT Kg. 13
LENGHT cm. 40
WIDTH cm. 24
BIT ATTACCHMENT SDS MAX STANDARD
MAX BIT DIAMETER 50 mm.
HYDRAULIC REQUIREMENTS
FLOW 16-30 L/min 4-8 gpm
IDEAL FLOW 20 L/min 5 gpm
PRESSURE 100-150 Bar 1500/2000 PSI
MAX BACK PRESSURE 18 Bar 250 PSI
BIT TYPE SDSMAX
The HD13 hammer drill can be used for underwater works, the underwater model as
specific bit attachment that is a simplified version of the SDSS MAX type ,
the normal SDS MAX quick type chuck is not adequate for marine use as it has internal
small parts that are not easy to be cleaned after use in salty water
PERFORMANCES
BLOW PER MINUTE 2100
ROTATION SPEED 260 rpm
HOSE REQUIREMENTS
For 20 meters flexible hoses connections use double hydraulic hoses type:
½” diameter, SAE 100 R1/A.
DOA suggest flush face couplers as per EHTMA standards .

SAFETY PRECAUTIONS
The operators and personnell in charge of the maintenance of this tool must read and
understand the simple instructions and advices containde in this manual before the drill or
beginning its maintenance.
WHAT NOT TO DO
NOTE
The following list describes the most common incorrect uses of the tool.
As it is impossible to foresee all the types of misuses possible, it is not sufficient to
guarantee total security of the operators.
-Do not use the tool near electric cables that are laying underground, hidden or walled in.
Serious enjuries may be caused by cutting an energized electric cable with the drill.
-Do not use the tool when wearing loose-fitting clothes, necklaces or with long hair that
could become caught in the tool, causing serious enjuries.
-Never point the tool in the direction of people.
-Do not use the drill with a leg over the handle or with one hand only. Kickback, caused by a
blocking of rotation, could cause serious enjuries.
-Do not inspect, clean or change the bits while the oil is in pressure. Always put off the
hydraulic source.
-Do not work with your face near the bit.
-Do not use the tool if it is an unstable or unbalanced position, on ladders or unstable
supports.
-Do not use the tool connected to sources of hydraulic power which the hydraulic flow and
pressure values are not known.
-Do not reach out trying to reach a far away points in particular if tool used on unstable or
unbalanced position, on ladders or unstable supports.
FURTHER SAFETY MEASURES
Always wear: helmet, goggles, ear defenders, protective gloves and safety footwear.
Send incautions spectators or unauthorized people away from the work place.
Keep the drill clean and dry. This ensures a firm grip.
Keep in good conditions and regularly check the wear state of bits and chisels.
Always connect the power pack hoses (or those of other power sources) to the hammer drill
before starting the engine.

BEFORE WORKING
CONNECTION OF THE TOOL TO THE POWER PACK OR OTHER HYDRAULIC
SOURCE
1. Lay down the flexible hydraulic hoses avoiding the contact of the couplers with
the mud or dirt.
2. Lay the tool on a clean surface. Make sure that the tool is in perfect condition
and that bits are well installed and that the spring return of the trigger is perfectly
efficient
3. First connect the flexible hoses to the power pack whose engine must be OFF.
Connect the female coupler of the hose to the male coupler of the power pack,
then connect the other hose.
IF CORRECTLY INSTALLED, THE MALE COUPLER INSTALLED ON THE POWER PACK IS THE ONE
CORRESPONDING TO THE PRESSURE LINE, WHERE THE OIL “GETS OUT” FROM THE POWER
PACK, THE CORRECT SEQUENCE OF COUPLERS INSTALLATION DEPENDS ON THE POSITIONING
OF THE FIRST MALE COUPLER THAT HAS TO BE INSTALLED ALLWAYS ON THE P LINE OF PACK.
USE OF THE HAMMER DRILL
OPERATIONS
The HD13 is a hydraulic hammer drill that can ben powered by hydraulic power packs or by
hydraulic circuits of earth-moving machines, mini excavators, trucks and vans etc…
Some version are equipped with a lever that allows to reverse the rotation, this feature allows
to easily retract the bit that may be blocked by a rebar into the material
The HD13 hammer drill is a tool that is implicit safe thanks to the absence of electricity , in
particular its use is ideal when the operator works in high presence of water or mud or with feet
in the water , so safe operations are guaranteed by the natural absence of sparks and risk of
electric shocks, is ideal for all jobs in particular for the maintenance of utilities network (water,
electric, telephone) and for underwater works.

Before using the tool, check the operational area, freeing if of objects that could cause
obstruction and ensuring that there are not electric cables or pipes walled in or under the part
to be drilled or demolished.
Prepare a sort of “working plan”, trying to foresee and avoid unexpected events, damage or,
worse, accidents.
1 - Connect the tool to the hydraulic hoses of the power pack (or other hydraulic source).
The pressure hose enters the hole in the tool at “IN” , is the port corresponding of the upper
hole where on the short hose is installed a female quick coupler .
2 - The discharging/ return hose ( Tank) comes out of the tool from the tube at the hole market
“OUT”, is the port corresponding of the lower hole where on the short hose is installed a male
quick coupler .
IF THE HOSES OF THE POWER PACK ARE LEFT IN THE SUNLIGHT FOR A LONG TIME, THE
EXPANSION OF THE OIL DUE TO THE HEAT COULD OBSTACLE THE PREVIOUS OPERATION.
WHENEVER POSSIBLE, CONNECT THE ENDS OF THE HOSES TO ONE ANOTHER.
3 - Choose the SDS MAX bits of the appropriate diameter
4 - Check the wear of the bits. If the bits in Widia or Tungsten are damaged or missing, even
the best drill will give poor performance.
STARTING ON /OFF
To start the tool, simply pull the trigger. To stop it, release the trigger. The number of
revolutions of the bit can be changed according to the pressure exercised on the trigger. Tthis
characteristic facilitates the initial approach when drilling hard materials.
DRILLING
Place the bit where the hole is to be made and pull the trigger. Do not force the tool. Light
pressure gives best results. Keep the drill in place and prevent it from slipping out of the hole.
If the holes become blocked by splinters or particles, instead of forcing the tool, let it idle then
pull the bit out of the hole, removing the rubble. By repeating this operation several times, the
hole will be completely cleaned and bits will rotate freely.
END OF OPERATIONS
1. LAY DOWN TOOL, TRY LIMITING CONTACTS WITH THE MUD AND DIRT
2. PUT THE FLOW LEVER OF THE POWER PACK IN OFF POSITION, THIS WILL TAKE AWAY FLOW
TO TOOL
3. PUT THE PACK ENGINE OFF

4. DISCONNECT THE TOOL FROM THE OIL FLEXIBLE HOSE RELEASING FIRST THE PRESSURE
HOSE ( IS THE UPPER HOSE NEAR THE HANDLE) CORRESPONDING TO THE HOLE WITH P – IN
THIS OPERATION WILL PREVENT ACCIDENTAL PRESSURE TRAPPING INSIDE THE TOOL.
5. DISCONNECT THE FLEXIBLE OIL HOSE FROM THE POWER PACK
6. ROLL UP THE OIL FLEXIBLE HOSE IN CIRCLES OF ABOUT 60 CM OF DIAMETER, CONNECTING
THE QUICK COUPLERS AT THE EXTREMITIES IN THE “HEAD/TAIL” WAY. THIS OPERATION WILL
PROTECT THE OIL COUPLERS AGAINST IMPACTS OR SCRAPING AND WILL ALSO HELP IN
KEEPING THE HOSE WELL ROLLED UP.
7. DETACH THE BIT FROM THE TOOL IF NEEDED, CONTROL THE STATE AND EFFICIENCY OF
THE BIT AND DISCARD THOSE DAMAGED TO AVOID THAT CAN BE REUSE
8. STORE THE EQUIPMENT IN A SAFE PLACE REPAIRED FROM BUMPS AND ATMOSPHERIC
AGENTS
9. IF THE EQUIPMENT SHOULD BE TRANSPORTED ON VEHICLES OR TRUCKS, TAKE CARE THAT
IT IS LOADED AND BLOCKED IN A PROPER WAY FOR AVOIDING TILTING AND DAMAGES.
AFTER USE IN UNDERWATER WORKS
AFTER THE USE IN UNDERWATER WORKS AND ABOVE ALL IN SALTY WATER
•- AFTER USE THE TOOL MUST BE IMMEDIATELY ACCURATELY WASHED WITH FRESH
WATER, INSISTING IN THE RECESSED CAVITIES AND HIDDEN POINTS WHERE SALT MAY
NEST
•- THEN WITH AN AIR GUN ACCURATELY REMOUVE ALL TRACES OF WATER ( THE FRESH
WATER )
•- THEN SPRAY TOOL WITH WD40 OR CRC OR OTHER DEWATERING MOISTURE RUST
NEUTRALISING PRODUCT
•- SPRAYING WELL WD40 OR CRC INSISTING IN THE RECESSED CAVITIES AND HIDDEN
POINTS
•- THEN BETTER WRAP TOOL IN A PLASTIC WRAP TO AVOID ANY CONTACT WITH METAL
AND SALTY AIR
•- IF POSSIBLE PLACE TOOL ON WOOD AND PLASTIC SURFACE ( NEVER ON METAL
SURFACE) IN A DRY PLACE THIS WILL PREVENT GALVANIC OXIDATION
MAINTENANCE AND CARE OF THE PRODUCT
CLEANING OF THE TOOL
THE TOOL CLEANING IS ESSENTIAL FOR THE GOOD FUNCTIONING OF THE EQUIPMENT. A CLEAN
PRODUCT WILL IMMEDIATELY ALLOW TO FIND OIL LEAKS OR CAUSES OF MALFUNCTIONING. A
CLEAN TOOL IS ALSO MORE COMFORTABLE FOR THE OPERATOR AND GUARANTEES A FIRM
GRIP.
CLEANING WITH CLOTHS OR PAPERTHE TOOL CAN BE CLEANED WITH A DAMP RAG, USING A
BRUSH WITH GASOHOL OR AN AIR GUN FOR ELIMINATING ALL TRACES OF DIRT AND OIL
CLEAN IN PARTICULAR THE RECESSED POINTS AND CAVITIES AND THE CONNECTION SURFACE
OF THE QUICK COUPLERS.

WITH THE TOOL PERFECTLY DRY, SPRAY A PROTECTIVE-DEWATERING PRODUCT (CRC-or WD40)
ON THE TOOL AND ON THE QUICK COUPLERS.
DRY UP COMPLETELY THE TOOL HANDLE TO GUARANTEE A FIRM GRIP
PERIODICAL CONTROLS
EVERY TIME THE EQUIPMENT IS USED :
1. CONTROL THAT THE TRIGGER RETURN SPRING IS EFFICIENT , AND THAT THE SCREWS,
THE VALVES, AND ALL COMPONENTS ARE WELL INSTALLED AND EFFICIENT, IN CASE
SOMETHING IS DAMAGED IMMEDIATELY DISCARD THE PART OR INFORM YOUR FOREMAN
SO THE PARTS WILL NOT BE REUSED
2. CLEAN THE TOOL AND ITS HOSES AND THE REST OF THE EQUIPMENT
3 - PERFORM A GENERAL INSPECTION OF ALL THE EQUIPMENT
MAINTENANCE OF THE OIL FLEXIBLE HOSE
INSPECTION OF THE HOSE
•Lay the flexible hoses on the floor and control if there are oil leaks and the hose
surfaces are integral without peeled sections showing metallic braid with broken steel
wires.
•the presence of little sections of wire braid can be tolerated only if the wires are not
broken and still braided.
•Control the pressed bushing at the extremity of the hydraulic hoses and discard
immediately hoses showing bending, squeezing, or deformations.
•Check that the quick couplers are well dry, without oil leaks and that the knurled
bushing on the female quick coupler is intact and can slide freely during the
connections. The male coupler should be intact, without dents and deformations. If you
try to force the connection of a damaged male coupler, this will damage irremediably
also the female.
•If the oil flexible hose and quick couplers show oil leaks, even if the couplers are well
screwed into the hose fittings, they should be immediately substituted with new parts.
•Replace hoses that show squeezing, unnatural bending, deformations, swellings, etc…
CARE AND MAINTENANCE OF THE OIL FLEXIBLE HOSES
The flexible hose can be cleaned with a hydro cleaner or pressure washer after having laid
it on a clean surface. Clean with the water jet in particular near the area of the clips where
the dirt is going to deposit.
Move the hoses and wash completely in particular the quick couplers.
Blow the hoses with an air gun in particular in the area of the quick couplers.
Roll up the flexible hoses in a roll having a diameter of about 60-70 cm and connect the
quick couplers at the ends in the “head/tail” way. This operation will protect them against
impacts or scraping.
Place the hose in a safe and dry place, protected from bumps and weather

IF A FLEXIBLE HOSE FULL OF OIL REMAINS UNDER THE SUN, THE OIL EXPANSION DUE TO THE HEAT CAN
CAUSE A PRESSURE INCREASE AND PREVENT THE CONNECTION OF THE QUICK COUPLERS. TO DECREASE
PRESSURE, LOOSEN THE QUICK COUPLERS, DRIPPING SOME OIL DROPS DE-PRESSURIZING THE HOSE.
THE FLEXIBLE HOSE ALWAYS REMAINS FULL OF OIL THAT, DEPENDING ON THE HOSE LENGTH, CAN HAVE
A RELEVANT VOLUME. IF YOU CHANGE THE HYDRAULIC OIL IN THE POWER PACK, IT IS RECOMMENDED TO
REPLACE ALSO THE OIL IN THE HOSES.
THIS WILL ASSURE A FULL REPLACEMENT AND AVOID THE CONTAMINATION OF THE NEW OIL.
DISPOSAL AND SCRAPPING
THE HYDRAULIC OIL – BATTERIES OF THE POWER PACKS
HYDRAULIC OIL FILTERS – ACID OF THE BATTERIES
ENGINE OIL – FLEXIBLE HOSES FULL OF OIL
ENGINE OIL FILTERS – ALL FUELS
ARE DANGEROUS WASTES
THAT MUST BE DISPOSED ACCORDING TO THE LOCAL REGULATION OF YOUR
COUNTRY OR MUNICIPALITY
DON’T THROW AWAY THE LIQUIDS AND MATERIALS OF THE ABOVE-MENTIONED LIST. THE
INFRINGEMENT OF THE RULES REGARDING THE DISPOSAL OF DANGEROUS WASTES IMPLIES
LEGAL RESPONSIBILITIES.
Also the storing and charging/discharging management of the materials of the above-mentioned
list have to be run according to the specific regulation.
For information about the handling and disposal of the dangerous wastes contact the
ENVIRONMENT department of your municipality.
Except for the liquids and materials of the previous list, the other components of the products
manufactured by DOA are fabricated with recyclable materials that can be stored, disposed and
scrapped without particular cautions.
MATERIALS AND COMPONENTS USED BY DOA DO NOT CONTAIN ASBESTOS OR OTHER
TOXIC ELEMENTS THAT REQUIRE SPECIAL CAUTION FOR THEIR USE.

REPAIR
DISASSEMBLY – INSPECTION OF THE PARTS – REASSEMBLY
DOA HYDRAULIC TOOLS ARE PROFESSIONAL PRODUCTS THAT SHOULD BE REPAIRED ONLY BY
QUALIFIED PERSONNEL.
THE TOOL REPAIR MAY REQUIRE TECHNICAL LITERATURE AND INSTRUMENTS FOR THE
CONTROL OF THE HYDRAULIC VALUES AND AN ADEQUATE HYDRAULIC SOURCE NECESSARY
FOR CARRYING OUT THE TOOL FUNCTIONING TESTS.
IT IS THEREFORE ADVISABLE NOT TO START THE COMPLETE DISASSEMBLY OF THE PRODUCT
IF YOU ARE NOT A TECHNICIAN AND IF PROFESSIONAL TOOLS AND EQUIPMENT ARE NOT
AVAILABLE
REPAIR OF PRODUCTS UNDER WARRANTY
IF THE PRODUCTS ARE STILL UNDER WARRANTY, THE REPAIRS MUST BE
CARRIED OUT ONLY BY DOA AUTHORIZED SERVICE AGENTS OTHERWISE THE
WARRANTY WILL BE AUTOMATICALLY NULLIFIED.
GENERAL INFORMATION
Although we recommend that the repairs have to be carried out only by authorized DOA service
agents, some minor repairs can be carried out also by other engineers, in this case follow these
instructions:
BEFORE DISASSEMBLY
•Clean accurately the product and remove any trace of dirt and solidified concrete.
•Keep available a clean working surface, paper, rags, tools, an air gun, a rubber hammer, a
brass punch, a vice with soft protection for the jaws, a clean container for collecting the tool oil.
•Keep available an exploded view of the tool and part list.
•Consider that when the tool is completely disassembled, it’s recommended to replace all
exposed seals.
OFTEN THE CAUSE OF FAILURE IS NOT DUE TO PROBLEMS OF THE HYDRAULIC TOOLS, BUT TO
PROBLEMS OF THE HYDRAULIC CIRCUITS WHICH COULD NOT HAVE PRESSURE AND FLOW
CORRECT VALUES. IF YOU SUPPOSE THIS, DO NOT DISASSEMBLE THE TOOL, DO NOT MAKE
EXPERIMENTS AND CONTACT THE NEAREST AUTHORIZED DOA CENTRE.

GENERAL PRE-INSPECTION
•CONTROL THAT THE TOOL IS INTEGRAL AND COMPLETE, AND THAT ALL BOLTS AND NUTS
ARE IN THEIR PLACE AND WELL TIGHTENED.
•CHECK THAT POSSIBLE SAFETY DEVICES AND THE RETURN SPRING ARE EFFICIENT,
WITHOUT DEFORMATIONS AND IN THEIR ORIGINAL STATE. IF THEY HAVE BEEN MODIFIED OR
REPAIRED ADAPTING THEM, DISCARD THEM AND ORDER NEW PARTS.
•IF SAFETY OR WARNING STICKERS ARE DAMAGED, ILLEGIBLE OR MISSING, ORDER NEW
PARTS CHECKING THE PART NUMBER ON THE TOOL PART LIST.
•CONTROL THE ACCESSORIES:, HYDRAULIC FLEXIBLE HOSES AND QUICK COUPLERS ARE OF
THE RIGHT TYPE AND INTEGRAL, ORIENTED IN THE RIGHT WAY AND THEY ARE NOT THE
CAUSE OF THE PROBLEMS.
•CONTROL THE QUICK COUPLERS ON THE TOOL AND ON THE FLEXIBLE HOSES, MAKE SURE
THEY ARE CORRECTLY INSTALLED, THAT THEY CAN BE CONNECTED IN THE RIGHT WAY TO
ASSURE THE RIGHT OIL DIRECTION.
•CONTROL THE FLEXIBLE HOSES, DISCARDING THOSE DAMAGED, WORN, SQUEEZED, ETC.,
CONTROL ALSO THAT THERE ARE NOT EXPOSED BRAIDS.
DISASSEMBLY
•REMOVE THE PIG-TAIL HOSES OR THE QUICK COUPLERS FROM THE TOOLS, MEMORIZING
THE ORIGINAL POSITION OF THE PARTS. REMIND THAT THE FEMALE QUICK COUPLERS
SHOULD BE INSTALLED ON THE TOOL IN THE HOLE WITH PPUNCHED (OIL ENTERS THE
TOOL), COLLECT THE DRIPPING OIL IN A CLEAN CONTAINER. CHECK IF THE OIL IS DIRTY,
OR WITH IMPURITIES, THIS WILL HELP IN FINDING SOME CAUSES OF PROBLEMS.
•IF A VICE IS USED FOR HOLDING THE TOOL, ALWAYS COVER THE JAWS OF THE VICE WITH
SOFT PROTECTIONS, AND BLOCK THE TOOL IN ITS MORE SOLID POINT, FOR NOT
DEFORMING THE PARTS.
•IF IT IS POSSIBLE TO MEMORIZE THE ORIGINAL POSITION OF THE SCREWS AND THEIR
TENSION.
•IF IT IS POSSIBLE TO DISASSEMBLE ONLY THE PART INVOLVED IN THE PROBLEM,
MEMORIZING THEIR ORIGINAL POSITION AND THE ORIENTATION OF THE SEALS.
THE HYDRAULIC COMPONENTS OF DOA PRODUCTS ARE MANUFACTURED WITH FINE
WORKMANSHIP AND STRICT TOLERANCES. BE CAREFUL NOT TO DEFORM AND DROP THEM. IT
IS COMPULSORY TO KEEP EVERYTHING CLEAN. WHEN IT IS POSSIBLE INSTALL PARTS WITH
MORE THAN ONE INSTALLABLE POSITION, IN THE ORIGINAL POSITION.
HYDRAULIC COMPONENTS INSPECTION
THE HYDRAULIC MOTOR SHOULD NEVER BE DISASSEMBLED. IF THE MOTOR SHOWS OIL LEAKS
OR OTHER DAMAGES IT MUST BE SHIPPED TO DOA FOR REPAIR
SEALS - O-RINGS
•CONTROL THE CONDITION AND AREA OF WEAR, TRYING TO FIND THE CAUSE (DIRTY OIL,
EXCESS OF TURNS, OTHER). IT IS ALWAYS BETTER TO REPLACE ALL SEALS THAT HAVE
BEEN DISASSEMBLED, IN PARTICULAR THE “DYNAMIC SEALS”, WHICH SEAL MOVING OR
ROTATING PARTS. THESE SEALS ARE MORE SUBJECT TO WEAR.

IF WORKING PROBLEMS REOCCUR OVER AND OVER, THE CAUSE OR CAUSES OF MALFUNCTIONING ARE
PROBABLY IN THE HYDRAULIC CIRCUIT. FOR SOLVING THESE PROBLEMS, CONTACT THE NEAREST DOA
SERVICE AGENT. THE TROUBLE SHOOTING CHART PROBLEM-CAUSE-SOLUTION AT THE END OF THIS
MANUAL GIVES SOME GENERAL INFORMATION ABOUT FUNCTIONING PROBLEMS LINKED WITH HYDRAULIC
CIRCUITS.
IF THE PRODUCT SHOULD BE SHIPPED:
DRIP THE TOOL COMPLETELY AND MAKE SURE THAT THE TOOL IS PERFECTLY SEALED AND
THAT THERE ARE NOT OIL OR WATER LEAKS DURING THE TRANSPORT.
USE AN ADEQUATE CONTAINER OR PACKAGING, SUFFICIENTLY STRONG AND PROPORTIONAL
TO THE TOOL WEIGHT, IN ORDER TO PROTECT THE TOOL AND MAINTAIN ITS INTEGRITY.
PROBLEM / CAUSE / SOLUTION
TRUBLE SHOOTING CHART
THE FOLLOWING TABLE IS A GUIDE FOR FINDING AND SOLVING THE MOST COMMON WORKING
PROBLEMS. THE CAUSES OF MALFUNCTION OFTEN DEPEND ON INADEQUATE VALUES OF THE
HYDRAULIC CIRCUIT. THE CONTROL OF THE :PRESSURE – FLOW - BACK PRESSURE VALUES
SHOULD BE CARRIED OUT WITH PROPER INSTRUMENTS AND OIL TEMPERATURE OF 50° C.
PROBLEM:
IT IS NOT POSSIBLE TO CONNECT THE HOSES TO TOOL
CAUSE SOLUTION
Quick couplers damaged or blocked or
inadequate
Control and change as necessary
Tool or hoses pressurised by residual
pressure
Verify and release some oil
drops after
having unscrewed the quick couplers

PROBLEM:
THE TOOL SHAFT DOES NOT TURN
CAUSE SOLUTION
Power pack flow lever left in OFF Put flow lever in ON delivering flow to tool
Problems of flow circulation Control hoses, quick
couplers and their
installation sequence,
The trigger or the ON OFF
valve are
broken or blocked
Control and repair
Broken hydraulic motor or broken drive
shaft
Control / repair or contact the nearest
DOA service agent
PROBLEM
THE BIT TURNS BUT THERE ARE POOR PERFORMANCES –
TOOL HAS NO POWER
CAUSE SOLUTION
The flow control valves integrated in the
tool are dirty, damaged or blocked
Control, clean or change
The power pack does not give sufficient
pressure
The power pack has low setting of the
relief valve
Control the power pack pressure delivery
Increase setting of relief valve of power
pack
Tool broken
Control and contact the nearest DOA
service agent

PROBLEM:
THE TOOL SPEED IS TOO HIGH OR TOO LOW
CAUSE SOLUTION
The tool trigger and its ON OFF valve are
broken
Control, clean, repair or change
The power pack gives low flow,
insufficient flow to tool – High back
pressure
Control the flow delivery of power pack in
case contact the nea
rest DOA service
agent
Broken tool or broken power pack or bad
oil circulation
Control or repair and contact the nearest
DOA service agent
Back pressure too high Control and reduce hose length
PROBLEM:
TOOL WORKS WELL BUT THERE ARE POOR PERFORMANCES
CAUSE SOLUTION
Drilling bits are inadequate to material or
to tool speed – Bad state of bit cutting
plaquettes or plaquette dull
Control and contact the nearest DOA
service agent
The material has plastic inside or bit has
encountered a steel rebar
Control if material is adequete to tool
work or change position of hole
High back pressure, hoses too long
Control and repair , in case unblock the
devise with a hand type system then
continue with tool

PROBLEM:
THE TOOL BIT KEEPS TURNING ALSO WHEN TRIGGER IS
RELEASED
CAUSE SOLUTION
Broken return spring of trigger STOP WORK IMMEDIATELY
Control , repair and contact the nearest
DOA service agent
The ON OFF valve of trigger is dirty Control and cl
ean, change and control
hydraulic power pack oil filter
WARRANTY
All parts produced by DOA s.r.l. are guaranteed for a period of twelve months from the date of
delivery to the final customer, against defect of: material, workmanship-assembly.
Cost of labour and transports are not covered by warranty and should be paid by the customer.
Parts and complete components not produced by DOA such as engines, compressors, alternators,
etc., are covered by the warranty of the manufacturer.
Batteries of power packs and “worn out “ accessories, such as chisel bits, drill bits, cut off discs,
flexible hoses, quick couplers, or other accessories that have not an identification number, are
covered by a LIMITED WARRANTY OF THREE MONTHS from the date of starting.
DOA reserves the right to substitute only those parts recognized to be defective after an inspection
of DOA engineers under warranty at its own expenses and in its own plant.
If the repairs during the warranty period are performed by the customers, DOA will reject any
charge for labour expenses.
THE WARRANTY WILL BE AUTOMATICALLY VOIDED IF:
•Repairs are performed using non original, adapted or modified parts.
•The maximum hydraulic values of pressure, back pressure and flow are exceeded, or the
filtration and other operative conditions of the hydraulic circuits are inadequate to power DOA
tools.
•If the tool has been modified or used in excessive heavy applications or different from its
natural applications.
•If the attached WARRANTY CARD is not properly filled and mailed to DOA.
In any case the warranty excludes any redraft or reimbursement for damages of any kind and there
are not other explicit or implicit warranties besides the above mentioned one.
FOR ANY CONTROVERSY, THE COMPETENT COURT IS IN COMO-ITALY