Laski TRENCHER TR 120H User manual

„Version 10.2019
1 z 48
OPERATING INSTRUCTIONS
TRENCHER TR 120
Model TR 120H

2
Foreword
Thank you very much that you have just purchased our product, the trencher TR60 HC. Our
company has been engaged in production of machines and equipment for many years and
has gained considerable experiences in this field. Quality of our machines is proven in 40
countries of Europe and Asia we export to.
This manual brings important instructions for users, i.e. instructions for putting the machine
into operation, work safety and operating experiences. You will learn how to carry out
maintenance, repairs and service and who is authorised for doing checks and other actions on
the machine.
Your local dealer will give you this manual with instructions for operation and maintenance
while taking this new machine over. Make sure if you understand everything. If not, do not
hesitate and contact your dealer and ask him for explanation. It is very important for you and
your work safety to understand all instructions given in this manual.
The firm Laski spol. s r.o. does not bear any responsibility for any claims resulting from
disobedience to the instructions given in this manual.
This operation manual includes also work safety instructions in various parts of the text. If
there is any work safety rule or instruction in general description, then this instruction is
indicated with the following symbol:

Trencher TR 120 H
Contents
FOREWORD..........................................................................................................2
CONTENTS............................................................................................................3
PRODUCT IDENTIFICATION...........................................................................7
WORK SAFETY INSTRUCTIONS.....................................................................8
UTILISATION.......................................................................................................8
NOT ALLOWED USE ..............................................................................................8
GENERALLY..........................................................................................................9
WORK SAFETY SYMBOLS....................................................................................13
NOISE AND VIBRATIONS .....................................................................................15
TECHNICAL DESCRIPTION...........................................................................15
PRODUCT DELIVERY......................................................................................19
HANDLING..........................................................................................................20
PRECAUTIONS IN DESIGN.............................................................................20
CONTROLS ..........................................................................................................21
TRANSPORT,HANDLING AND STORAGE .............................................................24
CHECKLIST BEFORE OPERATION .........................................................................26
STARTING THE ENGINE .......................................................................................27
PUTTING INTO OPERATION ........................................................................28
PUTTING THE TRENCHER ASIDE..........................................................................31
EMERGENCY SITUATIONS...................................................................................32
ROUTINE MAINTENANCE..............................................................................32
MAINTENANCE OF TRACKED UNDERCARRIAGE ..................................................32
MAINTENANCE OF CHASSIS.........................................................................35
LUBRICATION......................................................................................................36

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HYDROGENERATOR BELT TIGHTENING...............................................................36
MAINTENANCE OF ENGINE..................................................................................38
MAINTENANCE INTERVALS.................................................................................38
FAILURES AND TROUBLESHOOTING ....................................................................40
WARRANTY........................................................................................................44
SERVICE REPORT ............................................................................................45

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Product Identification
Our product is identified with its serial number stamped on the type plate placed on
the machine frame in front of the chain bar. Upon the take-over of the product we
recommend you to fill required data in the following form (1) concerning the given
product and your dealer.
Type of product:
…………………………………………………….
Serial number of product:
……………………………………………………..
Engine type:
……………………………………………………..
Serial number of engine:
……………………………………………………..
Dealer's address:
……………………………………………………..
Address of authorised service:
……………………………………………………..
Date of delivery:
……………………………………………………..
Warranty expiration date:
……………………………………………………..
Interruption of warranty period:
……………………………………………………..
The product type plate is located on the machine frame above the cooler.
The type plate includes:
-manufacturer's data
-product trade name
-model
-type
-serial number
- year of manufacture
- weight of machine
- CE marking
Type plate location

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Work Safety Instructions
Utilisation
-The trencher TR60 HC facilitates trenching works at cables and lines lying in
-gardens, schools and parks without moving too much earth. The trench itself is
up to 120 cm deep with a plain and clean unvaried profile given by the cutting
chain width. The machine is used for trenching in compact soils with small
stones in size up to 50 mm in one-man operation.
-This machine is allowed to work only on flat and even terrain or up the
permissible limits as to its climbing ability. In this case it is also rated to climb
slopes (perpendicularly to the contour) up to 12o.
Not Allowed Use
-Avoid any trenching if there can be some foreign matters
and objects, such as metal, glass cullet, stony debris, ceramics etc.
hidden in the field. Avoid excessive steering manoeuvres on asphalt
and concrete surfaces since these cause excess pad wear.
-Avoid working in the fields with gradients exceeding 12o.
-Avoid working on very soft or unstable ground. The machine could sink, slide,
slew or turn over.
-Cross the already made trenches only in the permissible way (see instructions
below).
-Avoid working on icy and frozen terrain (it applies also to frost-bound grassed
area).
-It is strictly forbidden to start working with removed or missing guards or with
faulty safety elements.
-It is forbidden to use this machine if operating temperature in the hydraulic
system exceeds 65oC.
Recommendations for rubber tracks:
-Avoid any contact of the rubber tracks with abrasive surfaces. Avoid
manoeuvring on hard, stony and uneven surfaces such as rock, stones, stump
roots, debris, gravel, etc.
-It is forbidden to drive the machine on steep slopes (along the contour) and in
small turning radius with risks of instability.

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Generally
-Before use of this machine the user (owner) is obliged to instruct operators
with this manual and all operating instructions in a provable way.
-This machine is allowed to be operated only by an operator who is over 18
years old, physically and mentally capable and demonstrably instructed with
its operation.
-This manual should be available and at operator's disposal any time.
-Persons under the influence of drugs, alcohol or medication affecting reaction
time must never work on or with this machine.
-Keep this machine beyond children's and unauthorised persons' reach. Avoid
their presence while working.
-Keep this machine beyond children's and unauthorised person's reach. Avoid
their attendance while trenching. Keep them beyond hazardous area which is a
space around the machine up to 5 metres.
-Pay special attention to the area on the trencher's right side where its auger
turns.
-Every operator of this machine is fully responsible for any injury or damage
caused to the third persons within the operating reach of the machine.
-Avoid working with inclination exceeding the permissible limit of
12o.
-Do not kip the machine to any side more than 22o–risk of damage of the
engine.
-Before work first observe the working area. To ensure maximum life of the
trencher and to keep the chain tips sharp, any contacts with stones, flint brick
and other hard materials around the base of the trencher should be kept to an
absolute minimum.
-Before first putting the machine into operation, ask your local dealer who can
instruct you in operation and functions of particular actuators and controls.
-While working, the operator is obliged:
to use only such a trencher which is in optimal operating condition, not
damaged through transport, storage of from previous operation,
It is strictly forbidden to do any technical changes on the machine without
prior permission of the manufacturer. Use always original spare parts. For
servicing or spare parts contact your dealer or an authorised service.
before trenching to learn all local regulations concerning noise and to respect
them,
This machine is allowed to work only on flat and even terrain. Avoid working
on very soft or unstable ground.
to stop trenching immediately if there are any undesirable objects in the soil,

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Should the chain bar be in full depth of 1200 mm, it is theoretically possible
that a stone up to 220 mm may pass between the auger and the machine frame.
In lower depth this theoretical size may be even 290 mm. However, in field
conditions, even a 60 mm stone may get jammed between the outer auger edge
and the machine frame. This implies that trouble-free stone passage through
the auger is in fact an accidental event. Based on it, the stone size that surely
does not get stuck is about 50 mm.
In the hydraulic distributor for the chain and the auger drive there is an in-built
check valve preset to 185 bar. Should the stone get stuck in the auger or block
the working chain, this check valve turns on and the auger with the chain will
stop. The operator should immediately turn off the auger and the chain drive
by means of a control lever on the distributor, stop the travel gear or
eventually lift up the chain bar and remove the blocked stone.

to stop trenching immediately if he hears any strange noises or vibrations that
may result from contact of the cutting chain with undesirable objects bringing
usually damage of the chain. Turn the machine off and first remove these
objects.
to respect all work safety instructions.
to check up functions of all controls and safety elements before putting the
machine into operation,
While working, wear always personal protective equipment - protecting shield
or goggles, protective gloves, working boots and working clothes properly
buttoned.
Avoid wearing free parts, such as ties, scarves and shawls, belts, jewellery etc.
In case of longer hairs use always a proper head piece. Otherwise, such a
person is not allowed to operate this machine.
-This manual describes also some common troubles and failures which could
occur and which are easy to be remedied by an instructed person. Other
problems and faults should be announced directly to the manufacturer, the
LASKI Service Centre that is always ready to help you.
-Before any checks or servicing stop the engine, disconnect the spark plug
cable and wait until any motion stops.
-Do not put any objects or tools on the machine.
-While displacing the machine on the plot the chain bar must be set
horizontally and the machine operator should stand in the given attendant’s
place.

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-The manufacturer does not bear responsibility for any damages or injures to
the third persons or to other equipment resulted from disobedience to
instructions given in this manual.
-When handing the machine over to another person make sure if all controls,
guards, other safety elements and its safety switch are complete and fully
functional.
-Do not remove guards and other safety elements. They serve for your safety.
-Keep the given intervals for checks of bolted joints. The first check should be
done after first three operating hours.
-Always after work clean all parts of the machine. For cleaning do not use fuel
or other oil products.
-At windy weather orientate the trencher in such direction to avoid exhaust
gases and dust bothering the operator. .
-Stop working if some parts running hot are covered with dust and soil
deposits. Clean such parts any time when required.
-Fill up the fuel tank before working and only if the machine is turned off. The
fuel tank must be cold.
-Do not fill the fuel tank while the engine is hot or still running.
-Keep fuel tank cap always properly closed while working.
-Do not start if some fuel has been spilled.
-Keep open fire away while filling the fuel tank.
-Keep the machine beyond reach of open fire.
-Some parts of the machine may run warm (exhaust manifold, gearings,
hydraulic elements). Do not touch them when the machine is still running or
having been just stopped.
-Do not touch the spark-plug wire while the machine is still in use.
-Do not let the engine running in high speed unreasonably.
-Do not change the engine adjustment, especially its speed regulator.
-Never change the chain gearing through an unauthorised action.
-Do not start this machine in confined or ill-ventilated spaces. Engine exhaust
gases contain poisonous carbon monoxide. Carbon monoxide is odourless,
colourless and can cause death if inhaled
-Do not use the machine under conditions of low visibility, especially at foggy
weather, when you may overlook persons coming. Operate it only at daylight
or with sufficient lighting.
-Before working learn all functions of individual controls and safety elements
and carry out functional checks before any use.
-Do not carry out any repairs that are specified for authorised services only.
-Do not carry out any repair where its solution exceeds your experiences.

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-Avoid wearing free parts, such as ties, scarves and shawls, belts etc. In case of
longer hairs use always a proper head piece. Otherwise, such a person is not
allowed to operate this machine.
-While working, wear always personal protective equipment –protecting shield
or goggles, protective gloves, ear protection, working shoes and working
clothes properly buttoned.
-Keep all the work safety symbols and markings legible, clear and undamaged.
-Warning! Keep safety distance from the chain bar in motion and all moving
parts (auger).
-While working, keep an eye on sufficiently free space in the required direction.
-It is strictly forbidden to place any ballast on the attendant’s ramp that may
disable the dead man control.
-It is also forbidden to start working with removed guards or with non-
functional safety elements.
Residual Risks
FUEL
Fuel can be injurious to the skin - wash off as soon as possible. If taken internally
seek immediate medical attention. Refer to your local fuel supplier for the MSDS
sheet.
Store fuel only in approved containers, in well ventilated, unoccupied buildings and away from
naked flames. Do not fill the fuel tank while the engine is running.
EXHAUST FUMES
Engine exhaust gases contain poisonous carbon monoxide. Carbon monoxide is odourless,
colourless and can cause death if inhaled. Avoid inhaling exhaust fumes and never run the
engine in a closed building or confined area with insufficient ventilation.
HOT PARTS
Engine components can get extremely hot from operation (exhaust manifold, gearings,
hydraulic elements). To prevent severe burns, do not touch these areas while the engine is
running - or immediately after it is turned off. Never operate the engine with heat shields or
guards removed.
ELECTRICAL SHOCKS
Never touch electrical wires or components while the engine is running - they can be sources
of electrical shocks.
CHAIN OR AUGER IN MOTION
When the engine is turned off, the auger and the chain continue to move for a short while. Do
not touch these parts until they stop –risk of injury.
BATTERY
Batteries contain acid which is corrosive and poisonous. Handle the battery with care. If
splashed there is a risk of burns and / or serious damage to eyes. Wash the affected area

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immediately with lots of clean water and seek medical advice immediately. Read the battery
MSDS sheet supplied by the manufacturer.
EXPLOSIVE GASES
Gases, if given off from the battery, are explosive. Keep any sparking and flames away.
PERSONAL SAFETY
The following personal protective equipment (P.P.E.) must be worn by the person operating
this machine and also all personnel within a 20 metre radius of the machine:
-forestry safety helmet as to EN 397 fitted with a visor as to EN 166
-heavy duty gloves as to EN 388
-full ear protection as to EN 352-3
-close fitting heavy-duty fully protecting clothing
-steel toe protection boots as to EN 345
-dust mask if the ground is very dry.
Noise and Vibrations
Operating noise may even exceed 85 dB(A) if measured in the operator’s place. While
working, the operator is obliged to wear appropriate hearing protectors.
DUST
If the ground is very dry, a large amount of airborne dust might occur. In this situation
a corresponding respiratory mask should be worn.
LIGHTING
Operate this machine only at daylight or with sufficient lighting in the workplace.
Work Safety Symbols
This article introduces work safety symbols (pictographs) used on this machine.
Under the relevant figure there is their location (position) on the machine. These
work safety symbols warn the operator against risks connected with the machine
use. Your respect to the symbol meaning is a precondition for your work safety.
The user is obliged to keep all the work safety symbols legible, clear
and undamaged. In case of any damage or illegibility ask your local
dealer or an authorised service for a new relevant pictograph.

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1
2
3
4
5
6
Read this
operating manual
before use.
Always follow
the manual while
maintaining,
servicing or
repairing the
machine and
disconnect the
spark plug cable.
Wear personal
protective
equipment –eye
protection,
hearing
protectors and
protective gloves.
Warning!
Rotating auger.
Hit and pull-in
hazard.
Keep safety
distance from
turning parts.
Warning! Keep
safety distance
from chain bar in
motion.
7
8
9
10
11
12
Keep safety
distance from
moving parts.
Warning! Fuel is
highly
flammable! Keep
open fire away!
Warning! Hot
parts of exhaust
manifold.
Warning!
Turning parts are
running out.
Warning! Close
all guards before
starting the
machine.
Warning! Risk of
high-pressure
liquid leakage.
13
14
15
16
17
18

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Lashing points.
Avoid working
with inclination
exceeding
permissible limit.
Wear protective
gloves.
Wear ear
protection.
Wear face
protecting shield.
Wear steel toe
protection boots.
Obr. 5 –Work safety symbols on the machine
Obr. 6 –Work safety symbols on the machine
Noise and Vibrations
Operation of this machine brings following emissions:
Operating mode/engine
KOHLER CH 980
Sound power LW(A) (dB)
110
Noise at max. speed LA(dB)
92,4
All measurements taken in accordance with: ČSN EN ISO 11201, ČSN EN ISO
3744
Technical Description
This is trencher designed as a self propelled machine to be controlled by an
attendant standing in the given attendant’s place (ramp). Its tracked chassis can
change its track width and its travel gear is powered by hydrodrive with continuous

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regulation. Adjustment of the track base can be done also by means of a hydraulic
cylinder. Profiled rubber tracks are stretched on rollers.
This machine is powered by the engine KOHLER CH 980, four-stroke, air-cooled,
power output of 35 HP. The engine is used also for hydraulic drives of the travel
gear and the trenching device.
Trenching Device
This device consists of a link chain which runs on a special bar. The chain links
hold tips that cut the soil and bring it to an auger. Above the bar there is a guiding
block which helps keeping flatness at trenching. It serves also as a fixed point at
displacement of the machine. The auger puts the soil aside approximately 15 cm
from a new trench.
The chain bar is height-adjustable and hydraulically controlled by hydraulic
cylinders. The guiding block for flat trenching is mounted close to the chain bar
edge. The chain tips are fitted as left and right and intended for cutting the soil and
bringing it to the auger.
Fully hydraulic control of the machine is based on actuators installed in the upper
part of machine. They are in fact hydraulic valves controlling particular functions.
The hydraulic system is designed for power transmission from the engine to the
working parts of the trencher. It comprises also hydraulic hoses, cooler with filters
and electromagnetic valves.
Technical Parameters
Parameter
Unit
Value
Overall length
mm
3250/2470
Overall width:
mm
870
Overall height:
mm
1360/1920
Weight:
kg
867
Tracks
180x37x72 FP
Speed
m/hod
20 ÷ 120
Travel speed
km/hod
4,2
Max. permissible inclination
o
12
Max trench depth
cm
120

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Trench width
cm
max. 200
Trenching chain
-
1,654“, with 80 pitches
ENGINE
Type:
-
KOHLER CH 980, four-
stroke, air-cooled
Fuel
-
unleaded petrol (ON 95)
Power output:
HP/kW
18,6/25 at 3600 rpm
Engine oil charge
l
1,9
Fuel tank capacity:
l
16
Hydraulic oil capacity
l
53
Hydraulic oil
-
OH HV46, ISO VG46
Cooling
-
air-cooled
Starter
-
electric
Battery
Pb, 44 Ah, 12 V
Transport
This machine can be transported to site either on a trailer or on a low-bed truck. It
is not designed for driving on public roads.
Rubber tracks are designed only for use on soft terrain, not for hard
and abrasive surfaces such as sand, stone, minerals, etc. Use of
rubber tracks on these surfaces can cause premature wear and
deformation, hence reducing useful life of the tracks.
Loading/unloading
Always perform the machine loading and unloading operation with the
trailer parked on a solid and level surface.
Ensure that the hand brake is on (if fitted) and the trailer wheels are chocked prior
to attempting to move the machine onto/from the trailer.
If loading on a gradient, always ensure that the trailer wheels are adequately
chocked. Failure to do so may result in the brake de-activating and allowing the
trailer to roll. Turn the trailer to an appropriate position and chock both trailer
wheels. Do not move the trailer with the machine engine running.
Remember to use a purpose-designed ramp or a loading platform for loading and
unloading the trencher. The ramp must be strong enough to support the weight of
the machine (min. carrying capacity of 1000 kg).

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Make sure the slope of the ramp is less than 12°.
For loading/unloading keep the tracks extended to maximum.
Before loading the machine clean thoroughly the ramp and the loading area.
Ramps or areas that are dirty with oil, mud or ice are slippery and dangerous.
Avoid steering when going up or down the ramps since this can be extremely
dangerous. If it is absolutely necessary to steer, first drive the machine back down
to the ground and off the ramps or back onto the vehicle / trailer bed and then
change the direction of travel and start back up or down the ramp again.
To load or unload the machine you can use also some lifting means (min. carrying
capacity of 1000 kg) with adequate chains, straps or cables.
Fasten retention chains, straps or cables to the machine chassis and on the loading
floor (see lashing point symbols). Do not put them over or against hydraulic hoses
or other rubber parts. Make sure that they do not cause damage to rubber tracks,
hydraulic hoses, elements or cylinders. Fasten each corner of the machine and
fasten the front arm to the trailer / vehicle bed with a chain / strap or a suitable
anchor.
Lashing points for loading and fixing on the trailer or truck body. For lifting of the rear part use the
upper lashing points, to fasten retention straps on the load floor use the lower ones. The front hole can
be used for both ways of cording.

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Product Delivery
-This product is delivered completely mounted and attached to a wooden pallet.
-While handling you may use a lift truck or a tackle with min. carrying capacity
of 1000 kg (suspension in the given lashing points only).
-For any handling you need min. ceiling height of 2 m.
-The manufacturer delivers this machine shrink-wrapped. The protective foil
protects the machine against weather effects but in no case against mechanical
damage, fall etc. The protective foil is recyclable; dispose it according to valid
local regulations.
-While putting the machine aside (e.g. at reloading), we recommend to place it
under a shelter.
-While unloading, put the product always on a solid and level surface.
-It is not allowed to put it on a labile base.
-It is not allowed to put any objects or tools on the machine or to pile two
machines on each other.
-This product is delivered completely mounted and attached to a wooden pallet.
-While handling you
may use a lift truck or
a tackle with min.
carrying capacity of
1000 kg (suspension in
the given lashing
points only).
-For any handling you
need min. ceiling
height of 2 m.
-The manufacturer
delivers this machine
shrink-wrapped. The
protective foil protects
the machine against
weather effects but in

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no case against mechanical damage, fall etc. The protective foil is recyclable;
dispose it according to valid local regulations.
-While putting the machine aside (e.g. at reloading), we recommend to place it
under a shelter.
-While unloading, put the product always on a solid and level surface.
-It is not allowed to put it on a labile base.
-It is not allowed to put any objects or tools on the machine or to pile two
machines on each other.
Handling
After delivery unload the machine from the transport pallet as follows:
-Cut the binding band carefully. Be aware, the band is tightened up and after
cutting its both ends may 'shoot out'. While cutting the band, use protective
gloves and goggles.
-Remove the chocks from the tracks.
-Fill the fuel tank, connect the battery, check up the oil engine level and try to
start the engine.
-Lift up the chain bar.
-Put the chocks to the pallet in the required direction and in spacing of the
required wheel track.
-Keep free space around the pallet for going down. Be aware of potential
insufficient de-aeration of the hydraulics. It might cause unwished motion
while going down.
-Be aware while the machine leaves the pallet –it may shortly accelerate.
Precautions in Design
This machine is provided with
safety guards protecting
against any contact with
rotating parts (hit and pull-in
hazard) and against hot parts
(exhaust manifold). The
guards are fixed, bolted down
and solid; only the guard over
the exhaust manifold is