Maruzen BH20EV User manual

FOR THE SAFETY PURPOSE, PLEASE READ THIS MANUAL THROUGHLY
BEFORE ATTEMPTING TO USE THIS BREAKER. ANY FALES
OPERATING PROCEDURES WILL CAUSE DAMAGES TO THE MACHINE.
ALWAYS KEEP THIS MANUAL TO AN EASILY ACCESSABLE PLACE.
HYDRAULIC HANDHELD BREAKER
MODEL BH20EV
OPERATING MANUAL
MARUZEN KOGYO CO., LTD.
CAUTION
(Nov 20, 2015)

2
FOREWORD
This manual is an important part of your equipment. It provides
rules and guidelines which will help you use this machine safely and
effectively. You MUST familiarize yourself with the functions and
operations by reading the manual thoroughly before you begin using
this machine. For your safety, it is especially important that you
read and observe all precautions in this manual and labels on the
machine. The precautions MUST be followed strictly at all times
when performing operation and maintenance. * Fail to follow the
guidelines and safety alerts in the manuals and on the machine, or
use this machine in alternative ways from the manuals may result in
system failure or serious personal injury.
Keep this manual with the equipment or in an easily accessible place
in all times for future reference. Make sure all personnel involved in
working on this machine can consult it periodically. In case this
manual should be lost or damaged, immediately contact us or your
dealer to purchase a new copy.
We recommend you always use Maruzen genuine components and
parts. Replacing components and parts from other sources may cause
damages to this machine and endanger operators.
MARUZEN KOGYO CO., LTD.
155-8 NAGABUSE, MISHIMA-SHI,
SHIZUOKA-KEN, 411-0824, JAPAN

3
CONTENTS
Safety Information .............................................................. 4 ～ 7
Safety Alert Classifications ........................................... 4
Safety Alerts .................................................................. 5 ～ 7
Introductions ....................................................................... 8
How To Adjust the Hammering Power ............................... 8
Specifications & Descriptions ............................................. 9
Precaution Labels and Positions ........................................ 10
Inspection before Each Operation ...................................... 11
Guidelines ........................................................................... 12 ～ 13
Operation............................................................................. 14 ～ 15
Daily Check Out .................................................................. 16
Periodically Inspection ....................................................... 16
Available Tools .................................................................... 16
Troubleshooting ................................................................... 17～ 18
Exploded View ................................................................... 19
Parts List ............................................................................. 20 ～ 21

4
SAFETY INFORMATION
To enable you to use this machine safely, safety precautions and labels
are given in this manual and affixed to the machine to give
explanations of situations involving potential hazards and of the
methods of avoiding such situations.
SAFETY ALERT CLASSIFICATIONS
The following safety alert symbols are used to inform you that there is
a potential hazardous situation that may lead to personal injury or
damage.
In this manual and on machines labels, the following safety alert
symbol are used to express the potential level of hazard.
** Safety alert symbols are to emphasize all operation which, if not
strictly followed, could result in a life-threatening situation, bodily
injury or damage to equipment.
DANGER
Indicates an imminently hazardous situation
which, if not avoided, could result in death or
serious injury.
WARNING
Indicates a potentially hazardous situation
which, if not avoided, could result in death or
serious injury.
CAUTION
Indicates a potentially hazardous situation which,
if not avoided, could result in minor or moderate
injury.

5
DO NOT OPERATE THE MACHINE UNLESS THE FOLLOWING SAFETY
INSTRUCTIONS HAVE BEEN THOROUGHLY READ AND UNDERSTOOD!
Do not operate the equipment if you are
or if your
1. taking medication, feeling drowsy, feeling unwell or feeling
tired.
2. under the influence of drugs or alcohol.
3. hands, feet, lower back or other parts of your body hurt or
being injured.
* Failure to observe this precaution can result serious injury or
even death.
WARNING
WARNING Before operating the equipment, be
sure to ware personal protective
equipments such as follows:
1. Helmet
2. Protective goggles
3. Protective boots
4. Safety gloves
5. Hearing Protection
SAFETY ALERTS

6
CAUTION Do not touch the machine with your bare
hands
1. The oil tank may become hot under continuous running
.
Do not touch the equipment with your bare hands.
2. Tools may become hot under continuous use, make sure
to ware gloves before any contact with the tools.
* Failure to observe this precaution can result getting
burned
CAUTION When lending someone the equipment
Make sure the safety instructions have been thoroughly
read and fully understood by the person who is going to use
the equipment.
WARNING Avoid Blank Hammering
Operating the equipment horizontally may cause the
chisel’s sudden flying out.
Excessive blank hammering may be considered equipment
abuse and may cause equipment damage.
Failure to observe this precaution can result damage to the
breaker.

7
WARNING Never operate the breaker when
bystanders are in the work area
1. Do not operate the breaker if any people are within
the area where flying debris or movement of the
breaker may injure them.
2. For preventing flying debris, make sure protection
fences are being set up.
Failure to observe this precaution can result personal
injury.
WARNING Be special cautions to high pressure
gas
1. High pressure gas was held inside the accumulator of
the breaker.
2. Do not loosen the nut unless it is necessary for
maintenance.
Failure to observe this precaution can result serious injury

8
INTRODUCTION
1. This hydraulic breaker is designed to be used for the following
purposes.
(1) Breaking concrete and asphalt
(2) Digging or breaking hard soil
(3) Compacting soil
(4) Cutting asphalt
2. DO NOT operate this breaker on the following situations:
(1) Drench part of the breaker or whole breaker into water or
seawater.
(2) Connect with power source which its oil flow and pressure exceeds
the range prescribed.
(3) Operating at oil temperature below 10℃ or over 90℃.
(4) Using with the other not genuine tools
(5) Operation below 10°C or over 40°C.
(6) Use the equipment for purposes other than stated in this manual.
If you want to use this breaker in other conditions except above,
always consult with us.

9
SPECIFICATIONS & DESCRIPTIONS
Weight 20kg (Without tool)
Dimensions L665mmxW410mm
Working Pressure 8 ～ 11 MPa
Max. Pressure 20.6 MPa
Oil Flow 20.5l
B.P.M. 1450bpm
Shank Size Hex. 1” x 108mm
Coupling 3/8” Couplers
Back Pressure 2.5MPa
Extension Hose 3/8” x 10m (with
Power Unit)
Hydraulic oil ISO VG32,
VG40 or equivalent
NOISE 84.3 dB(A)
Vibration 8.56c/sec2
Latch

10
Safety Labels
Part No. Part Name
① MPL1Z074A Label BY（warning）
② MPL1Z075A Label BZ (warning)

11
INSPECTIONS BEFORE EACH OPERATION
Inspection Items Countermeasures
1. Loose nut Tighten the loosen
nut
2. Loose of plug Tighten the plug
3. Loose of bolts Tighten the bolts
4. Loose of hose
fittings
Tighten the fittings
5. Wears of handle
grips Replace new one
6. Crack of control
lever
Replace new one
7. Damage of hoses Replace new ones
8. Oil leakage of
each parts Replace the seals
9. Damage of tool Replace the tool
10. Loose of tool Check the latch and
replace if necessary
For the purpose of keeping the breaker in good condition, make sure the
following items should be inspected each time before using. (Refer the drawing
below)

12
GUIDELINES
1. Always use Maruzen Genuine Tools. Use other than Maruzen
genuine tools may cause breakage of tools which may lead to the
damage of the breaker and personal injury.
2. Consult with us when using power source other than UH070
Maruzen power pack.
3. When connecting and disconnecting couplers, make sure dirt, dust
and other foreign substance does not enter or attach to couplers
and hoses.
4. Make sure the power source is OFF when connecting the breaker
to the power source. Or changing tools (Moil point etc)
5. Maruzen original tools are highly recommended. Consult your
dealer for more specifics of tools.
6. If the oil temperature is below 10℃, warm up the breaker before
start operating.
7. Pay attention to the followings while operating the breaker.
(1) Be cautious for not being injured by the front of the tool.
(2) Be cautious for not being tripped by the extension hoses.
(3) Make sure there are no obstacles at jobsite. (Be cautious not
being tripped by obstacles while operating)
(4) While pulling out the breaker from the broken objects, be
cautions for not being fall over.
(5) Make sure the breaker was placed in horizontally. Fail to
place the breaker horizontally after operating can cause
injury by sudden falling of the breaker.
(6) Be cautious not to injure your back while lifting the breaker.
8. In case of sudden hydraulic hose breakage and hydraulic oil belch
out. STOP the power source IMMEDIATELY.
9. Replace new hoses when they are worn or when oil exudes from
them.
10. When detach couplers, a small amount of oil may slip out. Make
sure that surrounding area does not get dirty by oil.
11. When detach from power source, attach two hoses to each other.
CAUTION

13
12. When frequently attach and detach to the power source, hydraulic
oil will decrease accordingly. Always make sure the hydraulic oil
level before operating and refill if necessary.
13. After the operation, use tool to push up the piston.
14. If the oil temperature is below 10℃, warm up the breaker before
start operating.
15. For long-term storage:
1) Connect breaker to hydraulic power pack, insert any wood
bar (∅20～25mm, L 350mm) into front end to push up
piston to the end.
2) Apply antirust on piston.
3) Apply oil all over breaker with wet cloth. Cover it properly
and make sure it is kept in a low humidity place.
4) Remove plug on front end and attach grease nipple for
applying grease.
Immediately STOP the power source if the breaker does not stop after
releasing the control lever. Ask Maruzen dealer for repair and
service before the next operation.
OPERATION
When connect this breaker to power source other than Maruzen
UH070 power unit, make sure the power source you intend to use is
within the range (oil flow, pressure etc) prescribed on page 9.
Preparation
1. Unlock the latch on the breaker and insert tool (moil point etc)
Turn around the tool(Hexagon tool) if it stuck on the half way of
inserting.
2. Lock the latch. Make sure the tool is firmly fastened.
CAUTION
Tool
Latch

14
3. Make sure there is no dust or dirt inside couplers before
connecting breaker to hydraulic power pack.
4. Active the power source. (Start the engine on the power pack)
Operation
5. The breaker and the breaking object should be on a right angle.
Press down the breaker with your body weight. Grip the control
lever and start hammering.
Breaker Hoses
Couplers: Make sure they are
clean before the attachment Extension Hoses
Right angle to the breaking
target
Start Hammering

15
6. Do not hammer the same place for over 30 seconds. If the target
object does not break within 30 seconds, change the hammering
point.
7. Do not blank hammering for over 10 seconds.
8. Stop the power pack when the job has completed.
9. Push up the tool so the piston return to the position.
10. Detach the extension hoses.
11. Attach both couplers which are on the breaker together to prevent
dust and dirt entering.
12. Unlock Latch, remove tool from the main body.
13. Remove mud and dirt on breaker thoroughly.
DAILY CHECK OUT
Check before each operation
1. Check if there is any oil leakage from hoses or breaker itself.
2. Check if there are any cracks or damage in tools.
PERIODICAL INSPECTION
Ask your dealer for the periodical inspections.
Inspection Items
Operating Hours
Nitrogen gas charge in accumulator
300 hours or 1 Year
Replacement of accumulator diaphragm
500 hours or 2 years
Replacement of Valve Rod O ring
500 hours or 2 years
Replacement o
f U
-
cup packing
500 hours or 2 years
Replacement of each O Ring
Every 3 years
Wear of Movable Bush
Every 250 hours or every year
Grease Movable Bushy
(8g)
Every 50 hours
* Accumulator Nitrogen gas pressure: 3.5MPa (35.7kgf/㎠)

16
AVAILABLE TOOLS
MOIL POINT For Breaking
CONCRETE CHISEL
For Breaking
ASPHALT CHISEL For Cutting Asphalt
SHOVEL For Digging Hard Soil
TAMPING RAMMER
For Compacting Soil and Sand
L = 400mm
L = 400mm
L = 400mm
L = 400mm
L = 400mm

17
Symptoms Causes Countermeasures
Grip the control lever but does not
start
1.
Power so
urce is off (Switch lever is
in OFF position)
2. Hoses are not connected
3. Couplers are not connected properly
4. Relief valve pressure is set too low
5. Damage of control valve
6. Control valve is stuck by foreign
substances
7. High pressure side and oil return
side was connected inversely
1.
Start the power source (Turn the
switch lever to On position)
2. Connect hoses
3. Check out if all the couplers have
been connected properly
4. Adjust pressure to 140～210kgf/㎠
(13.7～20.6MPa) *
5. Replace a new control valve *
6. Disassemble breaker, clean and
remove dirt and dust between
control valve and valve body *
7. High pressure hoses is connected to
the upper side of the breaker
Functionin
g but weak hammering or low
hammering speed
1.
Low rate of oil flow from power
source
2. Pressure in relief valve in power
source is set too low
3. Control valve does not function
properly
4. Back pressure is too high
1.
Turn the engine rotation rate up and
increase the rate of oil flow (Adjust
oil flow to the necessary rate)
2. Check displacement of hydraulic
pump*
3. Adjust pressure to the range of 11.7
～20.6MPa) *Remove and clean the
joint of control valve and valve body
*
4.
Use widen or shorter hose on the oil
TROUBLE SHOOTING

18
5.
Moveable Bush got stuck
returned side to lower the back
pressure to 2.5MPa or under.
5.
Disassemble and clean the breaker*
Hammering in normal speed, but week
hammering
1.
Low accumulator gas pressure
2. Damage of accumulator diaphragm
3. Temperature of hydraulic oil is
abnormally high.
1.
Refill Nitrogen ga
s
35.7kgf/㎠ (3.5MPa) *
2. Replace diaphragm *
3. Check power source. Clean radiator
and fan
Strong hammering and in high speed
1. High rate of oil flow
1. Turn the engine rotation rate down
to decrease the rate of oil flow
(Adjust oil flow to the right range)
The breaker stops hammering during
operation
1.
Couplers are not connected
2.
Damage of control valve
1.
Check each connected parts
2.
Replace a control valve *
Oil leakage from control lever
1. Damage, wear or harden of O ring
1. Replace O ring
*
Profuse
Oil leakage from front end
1.
Damage of U cup pack
ing
2. Damage of U cup packing due to the
scratch of piston rod.
1.
Replace U cup packing
*
2. Replace U cup packing, remove the
scratch on piston rod *
Latch is nearly coming off
1. Damage of lock spring
2. Ware of latch
1. Replace lock spring
*
2. Replace latch *
High pressure hose shakes intensely
1. Damage of accumulator diaphra
gm
1. Replace diaphragm
*
Release
the control valve but the breaker
does not stop
1. Foreign substance is caught in the
valve rod
1. Disassemble, clean and adjust *
For items with *, ask Maruzen dealers for service and maintenance.

19
EXPLODED VIEW
MODEL BH20EV

20
Ｎｏ．
Part No. Part Name Q’ty
Ｎｏ． Part No. Part Name Q’ty
1 MB19Z010A Cover 1 22
MB02E006A Diaphragm 1
2 MB19Y001B Cover 2 23
MB19Y002A Shell 1
*3
MB35Z009A Handle (Ｌ） 1 24
WS－06<<<<<<<<BH
Seal Washer 1
*4
MB19Z023B Handle (Ｒ） 1 *25
1120―413―D Cap Bolt 1
5 1120―414 Handle Grip 2 26
OS－15 O-Ring 1
6 MB35Z010A Control Lever 1 27
MB35Z017A Plug 1
7 MB19Z016A Lever 1 28
OBP－22 Back up Ring 1
8 MB19Z008B Pin 2 29
OP―22 O-Ring 1
9 MB19Z035A Washer 2 *30
MB32X002A Valve Body 1
10
MB19Z021A Pad 2 31
M2LTE120Ａ M6 Orifice(φ2.6） 1
11
MB19Z006A Pin 2 32
BH―8×70（Zn） Bolt 4
12
MB19Z024B Washer 2 *33
MB32Z003A Valve Bush 1
13
MB19Z020A Spring Washer 2 34
M1XTE108A Control Valve 1
14
MB19Z007A Spring 2 35
M1HTE107A Spring (P) 1
15
MB19Z019A Spring Washer 2 36
QB－5／16 Steel Ball 1
16
SH―5x8（Togarisaki）
Stopper Screw 4 *37
MB32Z004A Inner Tube (V) 1
17
BH―6×12 Bolt 2 38
MB19Z009A Through Bolt 2
18
MB19Z030A Guide Bush 2 39
WS－18<<<<<<<<BH
Seal Washer 2
19
K5Ⓑ1620 DU Bush 2 40
21091・3-35-- Hose 1
20
MB19Z011A Lid 1 41
21091・3-50-- Hose 1
21
CO―0644 O-Ring 1 42
QC―03M Coupler ( Male) 1