Stanley MB556 User manual

© 2015 STANLEY Black & Decker, Inc.
New Britain, CT 06053
U.S.A.
56598 3/2020 Ver. 20
USER MANUAL
Safety, Operation and Maintenance
MB556
MOUNTED
HYDRAULIC BREAKER

2 ► MB556 User Manual
DECLARATION OF CONFORMITY
ÜBEREINSTIMMUNGS-ERKLARUNG
DECLARATION DE CONFORMITE CEE
DECLARACION DE CONFORMIDAD
DICHIARAZIONE DI CONFORMITA
Hydraulic Tools
______________________________________________________________________
I, the undersigned:
Ich, der Unterzeichnende:
Je soussigné:
El abajo firmante:
lo sottoscritto:
Weisbeck, Andy
Surname and First names/Familiennname und Vornamen/Nom et prénom/Nombre y apellido/Cognome e nome
hereby declare that the equipment specified hereunder:
bestätige hiermit, daß erklaren Produkt genannten Werk oder Gerät:
déclare que l’équipement visé ci-dessous:
Por la presente declaro que el equipo se especifica a continuación:
Dichiaro che le apparecchiature specificate di seguito:
1. Category: Hydraulic Hammer Breaker
Kategorie:
Catégorie:
Categoria:
Categoria:
2. Make/Marke/Marque/Marca/Marca Stanley
3. Type/Typ/Type/Tipo/Tipo: MB556
4. Serial number of equipment:
Seriennummer des Geräts:
Numéro de série de l’équipement:
Numero de serie del equipo:
Matricola dell´attrezzatura:
All
5. Mass/Masse/Masse/Masa/Massa 752 lbs / 341 kg
Has been manufactured in conformity with
Wurde hergestellt in Übereinstimmung mit
Est fabriqué conformément
Ha sido fabricado de acuerdo con
E’ stata costruita in conformitá con
Directive/Standards
Richtlinie/Standards
Directives/Normes
Directriz/Los Normas
Direttiva/Norme
No.
Nr
Numéro
No
n.
Approved body
Prüfung durch
Organisme agréé
Aprobado
Collaudato
EN ISO
EN
Noise Directive
Machinery Directive
12100:2010
982:2008
2000/14/EC:2005
2006/42/EC:2006
Self
Self
Self
Self
6. Special Provisions: None 7. Measurements: Measured Sound Power Level 124 LwA
Spezielle Bestimmungen: Messungen Guaranteed Sound Power Level 128LwA
Dispositions particulières: Mesures Measured in accordance to Directive 2000/14/EC,
Provisiones especiales:Mediciones
Disposizioni speciali:Misurazioni
8. Representative in the Union: Patrick Vervier,Stanley Dubuis 17-19, rue Jules Berthonneau-BP 3406 41034 Blois Cedex, France.
Vertreter in der Union/Représentant dans l’union/Representante en la Union/Rappresentante presso l’Unione
Done at/Ort/Fait à/Dado en/Fatto a Stanley Hydraulic Tools, Milwaukie, Oregon USA Date/Datum/le/Fecha/Data 3-22-11
Signature/Unterschrift/Signature/Firma/Firma
Position/Position/Fonction/Cargo/Posizione Director of Product Development
3/22/2011
DECLARATION OF CONFORMITY

MB556 User Manual ◄ 3
TABLE OF CONTENTS
SERVICING: This manual contains safety, operation and routine maintenance instructions. STANLEY Infrastructure
recommends that servicing of hydraulic tools, other than routine maintenance, must be performed by an authorized
and certied dealer. Please read the following warning.
To ll out a product warranty validation form, and for information on your warranty,
visit www.stanleyinfrastructure.com and select the Company tab > Warranty.
Note: The warranty validation record must be submitted to validate the warranty.
SERIOUS INJURY OR DEATH COULD RESULT FROM THE IMPROPER REPAIR OR
SERVICE OF THIS TOOL.
REPAIRS AND / OR SERVICE TO THIS TOOL MUST ONLY BE DONE BY AN
AUTHORIZED AND CERTIFIED DEALER.
For the nearest certied dealer, call STANLEY Infrastructure at [phone] and ask for a Customer Service Representative.
SAFETY SYMBOLS.................................................................................................................................................4
SAFETY PRECAUTIONS .......................................................................................................................................5
TOOL STICKERS & TAGS ......................................................................................................................................8
OPERATION ............................................................................................................................................................9
TROUBLESHOOTING ..........................................................................................................................................15
MAINTENANCE.....................................................................................................................................................16
CHARGING THE ACCUMULATOR......................................................................................................................17
FLOW CONTROL KIT INSTRUCTIONS..............................................................................................................18
WEAR TOLERANCES...........................................................................................................................................19
PROPER USE & CARE OF TOOL BITS ..............................................................................................................20
FLOW TEST PROCEDURES ...............................................................................................................................23
DEFINITIONS ........................................................................................................................................................25
SPECIFICATIONS .................................................................................................................................................26
ACCESSORIES .....................................................................................................................................................27
MB556 POWER CELL ILLUSTRATION ...............................................................................................................28
HOUSING PARTS ILLUSTRATION......................................................................................................................29
MB556 PARTS LIST...............................................................................................................................................30
MB55600SS............................................................................................................................................................31
MB55600SS PARTS LIST / MB556 MOUNTING BRACKETS............................................................................ 32

4 ► MB556 User Manual
Always observe safety symbols. They are included for your safety and for the protection of the tool.
LOCAL SAFETY REGULATIONS
Enter any local safety regulations here. Keep these instructions in an area accessible to the operator and
maintenance personnel.
Safety symbols and signal words, as shown below, are used to emphasize all operator, maintenance and repair
actions which, if not strictly followed, could result in a life-threatening situation, bodily injury or damage to equipment.
This is the safety alert symbol. It is used to alert you to potential personal injury
hazards. Obey all safety messages that follow this symbol to avoid possible
injury or death.
This safety alert and signal word indicates an imminently hazardous situation
which, if not avoided, will result in death or serious injury.
This safety alert and signal word indicates a potentially hazardous situation
which, if not avoided, could result in death or serious injury.
This safety alert and signal word indicates a potentially hazardous situation
which, if not avoided, could result in death or serious injury.
This signal word indicates a potentially hazardous situation which, if not avoided,
may result in property damage.
This signal word indicates a situation which, if not avoided, will result in damage
to the equipment.
This signal word indicates a situation which, if not avoided, may result in damage
to the equipment.
SAFETY SYMBOLS

MB556 User Manual ◄ 5
WARNING
Do not operate the breaker unless the
following safety instructions have been
thoroughly read and understood! Read this
manual before installing, operating or
maintaining this equipment.
• A flying projectile from the breaker, breaker
tool, rock or other material may enter the
operator's compartment and cause serious
or fatal injury to the operator. Personal
protection equipment must be used.
• A flying projectile from the breaker, breaker
tool, rock or other material may cause
serious or fatal injury to bystanders. Never
operate the breaker when bystanders are in
the work area.
• On some machines/carriers, the breaker
can enter the operator's compartment if it
breaks loose and swings toward the
operator. Make sure that suitable impact
shields are used when operating the
breaker with this type of equipment.
• Do not operate the breaker unless all safety
decals described in this manual are in
place. The decals must be inspected
periodically to ensure that all wording is
legible. The decals must be replaced if
illegible. Replacement decals can be
obtained from your authorized Stanley
Distributor.
• When operating the breaker you must use
ear protection, eye protection, and
breathing protection.
Read the Manual
Wear Eye
Protection
Wear Hearing
Protection
Wear Breathing
Protection
WARNING
SAFETY PRECAUTIONS

6 ► MB556 User Manual
Tool operators and maintenance personnel must comply
with the safety precautions given in this manual and on
the stickers and tags attached to the tool and hose.
These precautions are given for your safety. Review
them carefully before operating the tool and before
performing general maintenance or repairs.
Supervising personnel should develop additional
precautions relating to the specic work area and local
safety regulations. Place the added precautions in the
space provided in this manual.
The MB656 Mounted
Hydraulic Breaker
will provide safe and
dependable service if
operated in accordance
with the instructions given
in this manual. Read and
understand this manual
and any stickers and tags
attached to the tool and
hoses before operation.
Failure to do so could
result in personal injury or
equipment damage.
Check the rules and regulations at your location. The
rules might include an employer’s work safety program.
Regulations may identify hazards such as working
around utility supply lines or hazardous slopes.
BE THOROUGHLY TRAINED BEFORE
OPERATING THE UNIT ALONE
• Operator training must start in an area without
bystanders and use all the controls until they can
control the machine fully under the conditions of the
work area.
• When learning to operate a machine, do so at a slow
pace.
KNOW THE WORK CONDITIONS
• The operator must know any prohibited uses or
work areas for the machine. For example, excessive
slopes and poor or dangerous terrain conditions
must be avoided.
OBEY SAFETY RULES
• Operate the breaker in accordance with all laws and
regulations which a󰀨ect you, your equipment and
the worksite.
• Do not operate the breaker until you have read
this manual and thoroughly understand all safety,
operation and maintenance instructions.
• The operator must be familiar with all prohibited work
areas such as excessive slopes and dangerous
terrain conditions.
• Do not operate the breaker until you read the carrier
equipment manual and thoroughly understand all
safety, operation and maintenance instructions.
The word “carrier”, as used in this manual, means a
backhoe or excavator or similar equipment used to
operate the breaker.
• Ensure that all maintenance procedures
recommended in this manual are completed before
using the equipment.
• The operator must not operate the breaker or carrier
if any people are within the area where they may
be injured by ying debris or movement of the
equipment.
• Know the limits of your equipment.
• Establish a training program for all operators to
ensure safe operation.
• Warning: Use of this tool on certain materials could
generate dust potentially containing a variety of
hazardous substances such as asbestos, silica or
lead. Inhalation of dust containing these or other
hazardous substances could result in serious
injury, cancer or death. Protect yourself and those
around you. Research and understand the materials
you are cutting. Follow correct safety procedures
and comply with all applicable national, state or
provisional health and safety regulations relating to
them, including, if appropriate arranging for the safe
disposal of the materials by a qualied person.
• Do not operate the tool unless thoroughly trained or
under the supervision of an instructor.
• Become familiar with the carrier controls before
operating the carrier and the breaker.
• When operating the breaker you must use ear
protection, eye protection and breathing protection.
• While learning to operate the breaker and carrier, do
so at a slow pace. If necessary, set the carrier mode
selector to the slow position.
• Make sure all controls (levers and pedals) are in the
NEUTRAL position before starting the carrier.
• While operating the breaker and carrier, keep hands
and feet on the controls at all times.
• Before leaving the carrier, always lower the boom
and insure the carrier is stable. Never leave the
machine with the engine running.ALWAYS ENGAGE
THE PARKING BRAKE.
SAFETY PRECAUTIONS

MB556 User Manual ◄ 7
• Stop the engine before attempting to make any
repairs, adjustments or servicing to either the carrier
or the breaker.
• Do not operate the tool at oil temperatures above
190 °F/88 °C. Operation at higher temperatures
can damage the internal components of the breaker
and carrier and will result in reduced breaker
performance.
• Do not operate a damaged, leaking, improperly
adjusted or incompletely assembled breaker.
• Do not modify the breaker in any manner.
• Use only tool bits supplied by STANLEY. Use of tool
bits supplied by another manufacturer may damage
the breaker and will void the warranty.
• To avoid personal injury or equipment damage, all
breaker repair, maintenance and service must only
be performed by authorized and properly trained
personnel.
• If you do not understand how to safely operate your
breaker, contact an authorized STANLEY dealer for
assistance.
• Keep this manual with the breaker.
• Do not operate this equipment if you are taking
medication which may a󰀨ect your mental judgement
or physical performance.
• Do not operate this equipment if you are under the
inuence of drugs or alcohol.
SAFETY PRECAUTIONS

8 ► MB556 User Manual
73005
MB556 Decal
56595
Main Accumulator Spec Sticker—300 psi
74730 (Excavator)
74732 (Skidsteer)
CE Specication Plate
74705 STANLEY Logo Sticker
74707 STANLEY Logo Sticker (Skid Steer)
47351
Composite Warning Sticker
47352
Lifting Point Decal
PN:73005
72074
Grease Sticker
66219
Guaranteed Sound Power Level Decal
TOOL STICKERS & TAGS
INSTANCE NAME fam.inst.param.name
fam.inst.name fam.inst.param.value

MB556 User Manual ◄ 9
PRE-INSTALLATION INSTRUCTIONS
SKIDSTEER, BACKHOE OR EXCAVATOR
SIZE
Check the Specications section of this manual to
determine correct carrier size, hydraulic ow and
pressure requirements.
If hydraulic pressure, hydraulic back pressure,
hydraulic ow or carrier weight class are exceeded,
the tool warranty is void.
EXISTING EQUIPMENT HYDRAULICS VS.
APPLICATION ATTACHING KITS
Using existing equipment hydraulic auxiliary systems
for operating hydraulic tools could cause problems for
the hydraulic tool and the hydraulic system if not set
up properly. Simply plugging into the hydraulic system
without conrming pressure and ow to the hydraulic
tool is not a good practice. Spare spool valves, dipper
circuits, etc., are just a few examples of easily accessible
hydraulic circuits which could prove to cause problems
for hydraulic tool usage.
TEST THE HYDRAULIC SYSTEM
1. Have your STANLEY dealer test the carrier hydraulic
system to make sure the system is operating at the
manufacturers specied capacity and pressure
ratings.
2. Be sure the uid in the hydraulic system is ltered
to at least 10 micro-meters. (Particles found in uid
should not exceed 10 micro-meters in size.)
3. Check the hydraulic lter. Replace the lter if dirty or
deteriorated.
4. Have your STANLEY dealer test the circuit to which
the breaker will be connected to make sure that the
circuit is supplying the specied ow and pressure
rating for the breaker. See the Specications section
of this manual.
PRE-OPERATION PROCEDURES
NITROGEN CHARGE
The breaker has been properly charged with nitrogen at
the factory and is ready to use.
TOOL BIT LUBRICATION
Grease the top 10 in. / 250 mm of the breaker tool
bit before installing. During operation, the tool can be
greased through the grease tting. Grease is required.
Make sure the tool bit is against the piston by placing
the tool bit against the ground and then putting down
pressure on the breaker. See the illustrations on page
11.
250 mm/10 in.
To o l B i t
Grease
This Area
of Bit
10 inches/250 mm
Figure 1. Greasing the Top of the Tool Bit
Greasing the tool bit without down pressure on the
breaker results in grease lling the space between
the piston and the tool bit. When the breaker is next
activated, the piston will strike the grease at a speed
which will pressurize the grease resulting in seal and
grease zerk failure.
OPERATION

10 ► MB556 User Manual
Piston in down position,
pressurized by Nitrogen in
accumulator
Tool bit pushed up
against the piston
No gap between
tool bit and piston
Tool bit NOT pushed up
against the piston
Gap - grease will ll
this space
Figure 2. Positioning the Tool Bit with Lubrication
SECURING THE TOOL BIT
1. The tool retainer is shipped installed in the breaker
(see parts illustration).
2. Drive out the tool retainer using a punch and
hammer.
3. Grease the top area of the tool bit as shown in
Figure 1.
4. Install the tool bit making sure the notch is aligned
with the lower body retainer pin hole.
5. Install the tool retainer.
Always wear eye protection when installing or
removing the tool retaining pin.
LOW TEMPERATURE WARM-UP
PROCEDURE
1. After starting the carrier, warm-up the hydraulic
system at engine idle until hydraulic lines are warm
to the touch.
2. With the carrier at idle and the breaker suspended
in the air or with minimal down pressure, turn
on the breaker to gradually warm up its internal
components.
3. When the hydraulic system and breaker are warm,
proceed with operation.
LONG TERM STORAGE
1. Remove the tool bit, clean the tool stop and the
lower bushing. Thoroughly coat the surfaces of the
tool stop and the lower bushing with grease.
2. If hoses are attached to the breaker, install plugs
on the hose ends. If hoses are removed from the
breaker, install plugs on the hose ends and install
plugs in the breaker IN and OUT ports.
3. Store the breaker in a vertical position. Do not store
the breaker horizontally for extended periods.
OPERATING A BREAKER
PREPARATION FOR USE
Read the section in this manual titled Pre-Operation
Procedures before operating a breaker. Failure to follow
the preparation instructions can result in severe damage
to the breaker and carrier, and void the warranties of
both.
POSITIONING THE CARRIER
SKIDSTEER LOADERS
With the breaker tool in place on the material to be
worked, position the skidsteer loader arms and the
breaker bracket so the breaker is almost vertical and the
front tires of the skidsteer are o󰀨 of the ground.
Keep lowering the loader arms as the tool penetrates
the work material so the skidsteer weight stays on the
tool. The breaker is more e󰀩cient when adequate down
force is applied.
Figure 3. Skidsteer Loader
OPERATION

MB556 User Manual ◄ 11
BACKHOES
With the breaker tool in place on the material to be
worked, position the backhoe so the boom is halfway up
(45°) and the dipper holds the breaker almost vertical.
Lower the loader bucket until the weight is o󰀨 the front
tires.
Apply down pressure.
Figure 4. Backhoe
Apply down force to the boom/dipper until the rear of
the backhoe is raised o󰀨 the ground. Rear tires and
stabilizers should be o󰀨 the ground so the total rear
weight of the backhoe is on the breaker tool. The breaker
is more e󰀩cient when adequate down force is applied.
EXCAVATORS
With the breaker tool in place on the material to be
worked, position the excavator so the dipper is at
approximately 45° and the breaker is almost vertical.
The tracks of the excavator should be in line with the
boom and the breaker.
Apply down force.
Figure 5. Excavator
POSITIONING THE BREAKER TOOL ON
THE WORK MATERIAL
Position the tool bit near the edge of the work material,
not in the center or far from the edge. Position the tool
6–18 inches (depending on the material) from the edge.
Breaking o󰀨 smaller pieces of rock or concrete usually
accomplishes more than trying to break larger pieces.
Break near the edge.
Figure 6. Position the Tool Bit
On at material or rock, the breaker should be vertical
or “curled” back slightly to direct the impact force
downward and toward the backhoe. This directs the
force back toward the edge of the work material. If the
tool is positioned in the center of the work, or too far from
the edge, the energy will be absorbed into the material
without cracking it. Do not run the breaker longer than
15–20 seconds. If breakout does not occur within this
time, move the breaker to another position.
On at material, such as concrete runways, starting to
break in the middle of the material may cause vibrations
to be transmitted throughout the breaker and excavator
because the material has no place to break to. Always
try to start at a point which will permit the material to
break out.
MAINTAIN DOWN PRESSURE
Maintaining hard contact with the surface of the material
to be broken in addition to maintaining adequate “down
force” is very important. Always keep “down pressure”
or “down force” on the point of the breaker by lifting the
wheels, tracks, or stabilizers slightly above the ground.
This method takes the “slack” out of the bracket and
boom pivots, and reduces the impact on the pivots in
the boom.
The operator needs to be constantly aware of the
OPERATION

12 ► MB556 User Manual
amount of down pressure being applied and be able
to adjust it if necessary. Not enough down pressure
results in low production and accelerates wear and tear
on the equipment. Too much down pressure may cause
the breaker housing to violently crash into the broken
material when “break-through” occurs.
In any breaking job, the operator should make every
e󰀨ort to “follow” the breaker with “down pressure” as the
machine breaks farther into the material. The breaker
should be stopped as soon as “break-through” occurs or
if it is apparent that good solid blows are not occurring.
BREAKING
The operator should note the sound of the blow when
the breaker is running. With experience, the operator
will be able to tell the di󰀨erence between a good solid
blow and a hollow sounding blow. A hollow blow means
that solid blows are not occurring and breaker should be
repositioned.
Continuous tool penetration usually does not do much
good. If the material does not break with 3–6 inches
of tool penetration, it usually won’t break with full
penetration. The time used for additional penetration
could be better used to strike blows in another place.
Many materials do not respond well to continued
hammering in one place. The breaker tool should be
repositioned on the work each time the tool penetrates
but does not crack the material.
Do not break continuously
in one place.
Do not break continuously
in one place
Figure 7. Breaking
Continuous penetration in the same area for lengthy
periods will create excessive temperatures at the tip
of the tool bit resulting in loss of temper (hardness)
of the bit, mushrooming of the tip of the bit and may
lead to failure of the bit.
Use a “scoring” method of breaking when cracking the
material becomes di󰀩cult. This technique involves
striking the rock or concrete at several places along a
line where you want the crack to occur. Most materials
break sooner when struck several places along a line
than when struck repeatedly in one location. On each
line, the breaker tool should be continually repositioned.
Practice determines the best length of time to stay in
one spot (15–20 seconds) and how far to move the
breaker tool.
Scoring with the breaker
Figure 8. Scoring with the Breaker
Breaker tool binding can cause erratic breaker operation
and premature wear on the tool shank. Breaker tool
binding is caused by failure to direct the down force in
the direction of the tool bit.
OPERATION

MB556 User Manual ◄ 13
Breaker tool bit binding
Figure 9. Breaker Tool Bit Binding
Do not pry with bit and breaker. The tool bit may
break causing injury.
Excessive side force cocks the tool in its bore, prevents
proper movement and causes premature tool shank and
bushing wear. Since the breaker tool bit must be pushed
up into the breaker to operate, a binding tool prevents
the breaker from operating correctly. Binding also causes
the tool bit and tool bushings to seize and often results
in breakage of one or more breaker components.
Always direct the down pressure force in a line toward
the point of tool contact with the work.
Moving rocks with the tool bit is another method of
binding the tool bit. This practice should be avoided as it
may cause tool bit failure.
Rebar reinforced concrete introduces the problem of
concrete chunks being held together by the rebar after
the concrete has been broken. The best approach to
this problem is to use a chisel point tool which permits
cutting the rebar with the breaker. Another method is to
periodically cut the rebar with an oxy-acetylene torch
BLANK FIRING
To understand “Blank Firing”, the operator needs to be
aware that the tool bit is able to drop down in the lower
body cavity, far enough so that the piston cannot strike it,
when the tool bit is not in contact with the work surface.
“Blank Firing” occurs whenever the breaker is operating
and the piston is not able to strike the tool bit solidly or not
strike the tool bit at all. “Blank Firing” accelerates wear
and tear on breaker and carrier components and may
result in failure of one or more components. Excessive
“Blank Firing” may be considered equipment abuse and
may result in voiding warranties.
Break-through or di󰀩cult surface contact results in
“Blank Firing” when the material being broken fractures
and the tool bit is no longer in “hard contact” with the
material but is still pushed high enough in the lower body
cavity so that the piston can strike it. In this position,
the piston strikes the tool bit and the tool bit, in turn,
is driven against the retaining pins because it is not in
su󰀩cient contact with the material to be broken. The
energy is absorbed by the retaining pins, other breaker
components, and the carrier boom components. “Blank
Firing” of this type can be experienced in trench work
where obtaining striking contact with the work surface is
di󰀩cult or the wrong tool bit is used, or in at rock work
where the operator fails to stop operation of the breaker
when slippage, fracturing or material break-through
occurs.
“Blank Firing” as a result of operator error occurs when
the tool bit is not in contact with the work surface to be
broken and is allowed to drop down in the lower body
cavity so that the piston is not able to strike it. Instead, the
downward movement of the piston will be stopped by an
internal oil cushion located at the bottom of the piston’s
stroke and the energy of the piston will be absorbed by
breaker components and excavator boom components.
“Blank Firing” of this type can be experienced when the
operator fails to stop operation of the breaker when the
material fractures or material break-through occurs, or
during re-positioning of the breaker.
While “Blank Firing” cannot always be avoided, it can be
kept to a minimum by avoiding the above conditions as
much as possible.
UNDERWATER USAGE
Underwater usage of the breaker will cause damage
to internal components. Even if the breaker is partially
submerged, water is introduced to an area between
the tool bit and piston. On the piston down cycle, the
water becomes compressed and damages adjacent
components.
OPERATION

14 ► MB556 User Manual
Do not use underwater without supplying air to breaker.
Do not use underwater without supplying air to breaker
Figure 10. Underwater Restrictions
No part of the breaker may be submerged in water.
Underwater usage of the breaker will cause internal
damage to the breaker. Consult STANLEY for
modications and specic warranty coverage if you
have an underwater requirement.
The breaker is equipped with an underwater port on the
side of the breaker. Connect an air line to this port and
supply the required air pressure and ow to the breaker
when using underwater. The following chart shows the
air ow rate and pressure required for various depths of
operation.
Depth/Feet Pressure/PSI
Air Flow Rate/
cfm
60 53 69
50 44 60
40 35 52
30 27 44
25 22 39
20 18 35
15 13 31
10 9 27
5 4 23
0 0 18
GREASE THE BIT
Grease should be applied to the upper end of the
breaker tool bit each time it is installed. Thereafter, the
tool should be greased at the tting to reduce wear in the
lower body and bushings of the tool. See Greasing The
Tool Bit in the sections titled Pre-Operation Procedures.
OPERATION

MB556 User Manual ◄ 15
This section describes how to nd and resolve problems
users may experience. If a situation occurs that is
not covered, call your STANLEY Customer Service
Representative for assistance.
PROBLEM CAUSE SOLUTION
Breaker will not re. Low hydraulic oil level. Fill reservoir.
No ow to breaker. Have hydraulic circuit tested by
authorized dealer/distributor per
approved procedure.
Main relief set low.
Internal damage. Have unit serviced by an authorized
dealer/distributor.
Damaged quick couplers. Replace.
Breaker runs slowly. Low hydraulic ow Have hydraulic circuit tested by an
authorized dealer/distributor per
approved procedure.
Excessive heat build up.
Excessive nitrogen pressure. Have unit serviced by an authorized
dealer/distributor.
Internal leakage.
Breaker runs erratically. Low or excessive back-pressure. Have carrier serviced by an authorized
dealer/distributor.
Damaged switch or connection.
Relief set too low.
Internal damage.
Tool binding. Add grease to tool shank. Do not pry
while operating.
Breaker runs but at reduced
power.
Low accumulator charge. Have unit serviced by an authorized
dealer/distributor.
Excessive back-pressure.
Relief set too low.
Breaker leaks oil around tool bit
and tool bushing.
Lower seals failed. Have unit serviced by an authorized
dealer/distributor.
Hydraulic system overheats. Main relief set low. Have unit serviced by an authorized
dealer/distributor.
Insu󰀩cient cooling capability in
hydraulic circuit.
Line/hose size too small.
Excessive back-pressure.
If symptoms of poor performance develop, the following
chart can be used as a guide to correct the problem.
When diagnosing faults in operation of the tool, always
check that the hydraulic power source is supplying the
correct hydraulic ow and pressure to the tool as listed in
the table below. Use a owmeter known to be accurate.
Check the ow with the hydraulic oil temperature at least
80 °F/27 °C.
Inspecting the tool or installing parts with the
hydraulic hoses connected can result in severe
personal injury or equipment damage. To prevent
accidental startup, disconnect the hydraulic power
before beginning any inspection or installation task.
TROUBLESHOOTING

16 ► MB556 User Manual
DAILY MAINTENANCE CHECKS
• Check for loose or missing fasteners. Tighten or
replace as needed.
• Inspect tool retaining pins and pockets for wear.
• Check for hydraulic leaks at all ttings and hoses.
Replace any defective hoses.
• Apply grease to the grease tting in the lower body
each morning. Grease as needed throughout the
work day.
TOOL STOP AND LOWER BUSHING
Inspect the tool stop and lower bushing for excessive
galling and metal pickup on the tool bit. Also check for
cracks. If cracks are present, the part must be replaced.
The extent of wear of the tool stop and lower bushings
and the tool bit can be checked by moving a NEW tool
bit back and forth and measuring the gap between the
tool bit and the lower bushing. If the gap is more than
.250 in./6 mm, the upper bushing, lower bushing and
tool bit should be replaced. A gap in excess of .250 in./6
mm will cause damage to the piston. Do not just replace
the tool bit or the lower bushing individually as this will
result in premature wear of the replaced component. It is
recommended to replace ALL worn components.
15 inches
Figure 11. Measuring Tool Bit Gap
MAINTENANCE

MB556 User Manual ◄ 17
The tools required to charge the breaker accumulator
are the Charge Hose assembly (505232) and the
Accumulator Tester (28257), which are used with
other STANLEY model breakers. When charging the
accumulator, make sure the tools and charge valve is
clean. Dirt can contaminate the charge valve and cause
leakage.
1. Remove the protective plug from the accumulator
charge valve. NOTE: There are two accumulators
on this breaker, the main accumulator and return
line accumulator.
2. Hold the chuck end of the tester and turn the gauge
fully counter clockwise to ensure the plunger inside
the chuck is completely retracted.
3. Screw the tester into the breaker charge valve by
turning the chuck. Do not use the gauge for turning
as this will advance the plunger in the chuck. Tighten
the chuck lightly against the breaker charge valve.
4. Turn the gauge clockwise to advance the plunger
until a pressure is indicated on the gauge. Do not
overtighten.
5. If the pressure is correct, unscrew the gauge to
retract the plunger. Then, loosen and remove the
tester from the charge valve. If the pressure is not
correct, proceed to Step 6.
Note: When disengaging the tester a “POP” of
nitrogen is normal.
6. Connect the charge hose assembly to the charging
valve on the tester. Make sure the valve on the
charge hose assembly is closed. Open the valve on
the nitrogen bottle.
7. Very slowly open the valve on the charge hose
assembly and slowly meter the nitrogen into the
breaker charge valve until the tester reads the
correct charge pressure.
8. When the correct pressure is obtained, close the
valve on the charge hose assembly and on the
nitrogen bottle. Unscrew the gauge to retract the
plunger. Loosen and remove the tester from the
charge valve. Before replacing the protective plug,
inspect the plug O-ring. If damaged or deformed,
replace the plug. Apply Loctite™ 242 to plug and
cap.
Main Accumulator
P/N 28257 Tester
P/N 505232 Charge Hose Assy
CHARGE PRESSURE SPECIFICATION
Main Accumulator: 300 PSI +/- 10 PSI
21 BAR +/- .7 BAR
Main Accumulator
Charge Port
Location
P/N 28257 Tester
CHARGING THE ACCUMULATOR

18 ► MB556 User Manual
The Flow Control Kit is an option for Skid Steer Models.
The Flow Control Kit regulates the ow from the skid
steer hydraulics to the breaker to prevent over-speeding
of the breaker. Follow the instructions below to install
the kit.
• Install the ow control block between the breaker and
the loader’s hydraulics using the 7/16 in. capscrews,
washers, and nuts provided. (Torque to 41 ft-lbs)
• Connect the hoses.
The parts list for the Flow Control Kit is shown below.
HOSE ROUTING
R = Return. Route to the breaker OUT port.
S = Supply. Route to the breaker IN port.
P = Pressure. Route to the tractor’s hydraulic pressure.
T = Tank. Route to the tractor’s hydraulic reservoir.
4
R
S
P
T
35
8
2
1
6
7
ITEM
NO. PART NO. QTY DESCRIPTION
1 34621 1 FLOW CONTROL BLOCK
2 34839 6 WASHER
3 371516 3 NYLOCK NUT
4 02773 4 ADAPTER
5 58653 1 ORIFICE LOCATED UNDER
FITTING DESIGNATED AS "S"
6 58652 3 CAPSCREW
7 58654 2 HOSE
8 58655 2 HOSE
Figure 13. Flow Control Kit
FLOW CONTROL KIT INSTRUCTIONS

MB556 User Manual ◄ 19
NEW REJECT LIMIT
LOWER BUSHING (ITEM 19)
2.775 in. / 70.5 mm 2.890 in. / 73.5 mm
TOOL STOP (ITEM 18)
A) 2.775 in. / 70.5 mm
Inside Diameter
A) 2.890 in. / 73.5 mm
Inside Diameter
B) .60 in. / 15.2 mm
Depth B) .48 in. / 12 mm Depth
RETAINER PIN (ITEM 17)
1.745 in. / 44 mm
Outside Diameter
1.660 in. / 42 mm
Outside Diameter
RETAINER PIN (ITEM 16)
.25 in. / 6 mm
Outside Diameter
.18 in. / 4.6 mm
Outside Diameter
PISTON
1.800 in. / 46 mm Depth 1.760 in. / 45 mm
FIGURE 14. LOWER BUSHING
FIGURE 16. RETAINER PIN
FIGURE 15. TOOL STOP
Wear Areas
C=Measure at 1.2 in./30 mm
AB
C
FIGURE 17. PISTON
New Part
Wear Limit
WEAR TOLERANCES

20 ► MB556 User Manual
Tool bits are made and heat treated to specication.
Tool bits, however well made, are wear parts and are
used in the most destructive applications. Even when
the hydraulic breaker is used properly, and the operator
is an experienced one, a tool bit may become damaged.
When a tool bit has been damaged, it is useful to
determine the cause immediately in order to prevent the
damage from occurring again.
All STANLEY tool bits are machined and hardened for
maximum performance. Care must be taken to maintain
the tools original condition for optimum productivity and
life expectancy. It is not uncommon for an operator who
is unfamiliar with using a hammer to break a point. This
is part of the learning experience.
Listed below are several methods to determine tool
failure and will quickly aid in warranty determination.
TOOL FAILURE NOT COVERED
UNDER WARRANTY
BLANK FIRING OR FREE RUNNING
This occurs when the tool is not in proper contact with
the work, thus causing the energy produced by the
hammer to be concentrated on the tool retainer(s) and
the retainer slot(s) on the tool itself. Caution should be
used to prevent the hammer from sliding o󰀨 slanted
surfaces or when breaking through thin material.
The illustration below is typical of the kind of breakage
that occurs from excessive blank ring.
Figure 18. Excessive Blank Firing Breakage
WORN-OUT FRONT BUSHING(S) OR
RETAINER PIN(S)
Worn-out front bushing(s) will cause the tool to become
misaligned inside the hammer. This misalignment will
cause uneven contact between the piston and tool,
thus causing stress to concentrate on one particular
area of the tool. This can also cause the tool to bind
inside the hammer. Call your dealer for acceptable wear
allowances.
Worn out retainer pin(s) will cause uneven loading on
the pin(s) themselves, causing failure of the tool or
retainer pin(s). This will also cause excessive wear to
the front bushing(s).
METAL-TO-METAL CONTACT
Extreme caution should be used to avoid scratches or
gouges on the surface of the tool. These areas create a
stress concentration metal-to-metal contact point, thus
weakening the tool.
Another form of metal-to-metal contact is galling, which
usually occurs from the lack of lubrication. Special care
should be taken to keep the tool shank lubricated every
two (2) to three (3) hours.
Steel failures that were caused by surface damage take
two main forms. The simplest form is caused by deep
scratches on working steel surface. The broken surface
has a shell pattern around the starting point of failure,
similar to the one in the fatigue failure. The other parts of
the broken surface are brittle. These failures work slowly
through the steel until it suddenly parts completely.
The second form of failure caused by surface damage
occurs when there are deep scratches on working steel
surface and there was also excessive bending stress.
The broken surface also shows the shell pattern, but the
other parts of the broken surface are brittle and usually
have a “lip” like that in a stress failure.
Figure 19. Metal-to-Metal Contact Examples
In its most extreme forms, the combination of surface
damage and severe bending can quickly break even the
best working steels.
The illustrations below show examples of severe stress
breaks.
PROPER USE & CARE OF TOOL BITS