KUHN GMD24 User manual

Original instructions
KN226BGB_A
Read carefully before starting the machine
Operator's manual
Disc mower
---A1025-70B00001 > ---A1025-70B99999
GMD24-GMD28 / HD
KN226BGB_A - English - 07-2019
*KN226BGB_A*

1. - Dear Owner
GMD24-GMD28 / HD
3
KN226BGB_A
Disc mower
1. Dear Owner
In buying a Kuhn machine you have chosen wisely. Into it have gone years of thought, research and
improvement. You will find, as have thousands of owners all over the world, that you have the best that
engineering skill and actual field testing can produce. You have purchased a dependable machine, but only
through proper care and operation can you expect to receive the performance and long service built into it.
This manual contains all the necessary information for you to receive full efficiency from your machine. The
performance you get from this machine is largely dependent on how well you read and understand this
manual and apply this knowledge. Please DO NOT ASSUME YOU KNOW HOW TO OPERATE AND
MAINTAIN YOUR MACHINE before reading this manual carefully. KEEP THIS MANUAL AVAILABLE FOR
REFERENCE. Pass it on to the next owner if you re-sell the machine.
Your KUHN dealer can offer a complete line of genuine KUHN service parts. These parts are manufactured
andcarefullyinspectedinthesamefactorythatbuilds the machineto assure high quality and accurate fitting
of any necessary replacements.
About improvements
We are continually striving to improve our products. We therefore reserve the right to make improvements
or changes when it becomes practical to do so, without incurring any obligations to make changes or
additions to the equipment sold previously.
Wear parts
Wearing parts fitted on our machines have been tested in very different situations to optimize their service
life. Nevertheless, the service life depends highly on the conditions of use (products to handle, soil, weather
conditions, etc...).
Document illustrations
The illustrations in this manual may be based on one type of machine only. However, all instructions apply
to all machines covered in this manual.
Copyright 2019 KUHN

GMD24-GMD28 / HD
42. - Contents
KN226BGB_A
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2. Contents
1. Dear Owner .....................................................................................................................3
2. Contents..........................................................................................................................4
3. Identification of the machine.........................................................................................7
3.1 Front view ........................................................................................................................................ 7
3.2 Rear view......................................................................................................................................... 7
3.3 Identification of the machine............................................................................................................ 8
3.4 Optional equipment........................................................................................................................ 10
4. Safety.............................................................................................................................11
4.1 Description of symbols used in this document................................................................................11
4.2 Safety instructions ......................................................................................................................... 12
4.2.1 Introduction....................................................................................................................... 12
4.2.2 Read and follow the safety instructions............................................................................12
4.2.3 Precautions to be taken before carrying out any operations on the machine................... 13
4.2.4 Precautions to take before using the machine ................................................................. 13
4.2.5 Precautions when coupling...............................................................................................14
4.2.6 Precautions when driving ................................................................................................. 14
4.2.7 Hydraulic circuit................................................................................................................ 15
4.2.8 Precautions when driving on public roads........................................................................ 15
4.2.9 Maximum speed...............................................................................................................19
4.2.10 PTO shaft..........................................................................................................................19
4.2.11 Waste disposal .................................................................................................................21
4.2.12 Remote controlled components........................................................................................21
4.2.13 Safety decals.................................................................................................................... 22
4.2.14 Precautions for maintenance and repair work.................................................................. 22
4.2.15 Projection of stones and foreign objects........................................................................... 23
4.2.16 Precautions during manoeuvres....................................................................................... 23
4.2.17 Precautions for machine use............................................................................................ 24
4.2.18 Precautions to take before using the parking stands........................................................ 24
4.3 Location and description of safety decals on the machine ............................................................ 25
4.3.1 Location of safety decals..................................................................................................25
4.3.2 Description of safety decals.............................................................................................. 26
4.4 Road safety equipment and recommendations ............................................................................. 29
4.5 Likely critical failures......................................................................................................................29
4.6 Incorrect use of the machine by the user....................................................................................... 30
4.7 Limit state criteria........................................................................................................................... 30

2. - Contents
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5. Machine specifications................................................................................................ 31
5.1 Description and glossary ............................................................................................................... 31
5.1.1 Designated use of the machine........................................................................................ 31
5.2 Technical specifications................................................................................................................. 32
5.2.1 Designated parameters.................................................................................................... 32
5.3 Required equipment...................................................................................................................... 33
5.3.1 PTO shaft ......................................................................................................................... 33
5.3.2 Cutter bar ......................................................................................................................... 33
5.4 Sound levels.................................................................................................................................. 34
6. Putting into service...................................................................................................... 35
6.1 Description of control elements ..................................................................................................... 35
6.2 Coupling and uncoupling............................................................................................................... 35
6.2.1 Description of coupling elements ..................................................................................... 35
6.2.2 Preparing the tractor......................................................................................................... 36
6.2.3 Preparing the machine..................................................................................................... 37
6.2.4 Coupling the machine.......................................................................................................38
6.2.5 Hydraulic connections......................................................................................................39
6.2.6 Electrical connection ........................................................................................................ 39
6.2.7 Check chain...................................................................................................................... 39
6.2.8 Primary PTO shaft............................................................................................................ 40
6.2.9 Adjusting the machine......................................................................................................41
6.2.10 Uncoupling the machine................................................................................................... 45
7. Instructions for transport............................................................................................ 47
7.1 Putting the machine into transport position ................................................................................... 47
7.2 Conformity with the road regulations............................................................................................. 49
7.3 Machine transport using transport means ..................................................................................... 49
8. Instructions for work................................................................................................... 50
8.1 Putting the machine into work position.......................................................................................... 50
8.2 Adjustments in working position .................................................................................................... 51
8.2.1 Cutting height................................................................................................................... 51
8.2.2 Outer swath disc............................................................................................................... 52
8.3 Machine use .................................................................................................................................. 53
8.3.1 Drive speed...................................................................................................................... 54
9. Optional equipment..................................................................................................... 55
9.1 1 3/8’’ - 6 spline pto shaft (With free wheel clutch)........................................................................55
9.2 Female coupler.............................................................................................................................. 55
9.3 Raised skid shoes ......................................................................................................................... 55
9.4 High cone disc kit .......................................................................................................................... 56
9.5 Inner swath disc............................................................................................................................. 56

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9.6 Inner swath shield.......................................................................................................................... 56
9.7 Side deflector.................................................................................................................................57
9.8 Side deflector with high cone disk ................................................................................................. 57
9.9 Frame connection arm/cutterbar.................................................................................................... 57
9.10 Lighting and signalling ................................................................................................................... 58
9.10.1 Electrical connection.........................................................................................................58
9.11 Lateral signalling equipment (Only for France)..............................................................................58
9.12 Lighting and signalling (Only for USA)........................................................................................... 59
9.12.1 Electrical connection.........................................................................................................59
9.13 Compensating spring..................................................................................................................... 59
9.14 Toolbox .......................................................................................................................................... 60
9.15 Wear skids..................................................................................................................................... 60
10. Maintenance and storage ............................................................................................61
10.1 Frequency chart............................................................................................................................. 61
10.2 Lubrication .....................................................................................................................................62
10.2.1 PTO shafts........................................................................................................................ 63
10.2.2 Draining............................................................................................................................64
10.3 Maintenance .................................................................................................................................. 67
10.3.1 Belt tension....................................................................................................................... 67
10.3.2 Breather plug checking and cleaning ............................................................................... 69
10.3.3 Checking cutterbar oil level ..............................................................................................69
10.3.4 Inspection of knives and securing elements.....................................................................70
10.3.5 Knife replacement.............................................................................................................73
10.3.6 Disc replacement..............................................................................................................74
10.3.7 Outer and inner cones......................................................................................................75
10.4 Storage .......................................................................................................................................... 76
10.4.1 At the end of each season................................................................................................ 76
10.4.2 At the start of each season...............................................................................................76
10.4.3 Storage............................................................................................................................. 77
10.5 Dismantling and scrapping of the machine....................................................................................77
11. Troubleshooting guide.................................................................................................78
12. Appendix.......................................................................................................................79
12.1 Calculating the load on an axle...................................................................................................... 79
13. Limited Warranty ..........................................................................................................87

3. - Identification of the machine
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3. Identification of the machine
3.1 Front view
3.2 Rear view

GMD24-GMD28 / HD
83. - Identification of the machine
KN226BGB_A
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3.3 Identification of the machine
- Do not remove the manufacturer,
homologation and marking plates attached
to the machine.
3.3.1 Location of the plates
- Please write below the type and serial number of
the machine:
• Serial Number:
- This information is to be given to the Kuhn
authorized dealer for any spare parts order or
warranty claim.
3.3.2 Description
Model identification plate
1: Manufacturer name and address
3: Brand
4: KUHN logo
5: Description of the machine
7: Model
9a: Machine serial number
9b: Barcode (Machine serial number)
12: Weight empty (Minimum/Maximum)
18: Data matrix
19: Plate reference
27: Place of manufacture
28: Manufactured by... for...
34: Special operation
9: Serial Nr. 34: Ex
5: Machine
7: Model
09993000
3: Brand
kg
kg
12: Unladen Mass min/Max
3: 商 Brand
9: 机架号 Serial Nr. 34: Ex
5: 机器描述 Machine
7: 型号 Model
kg
12: 卸重量最小/最大Unladen Mass min/max kg
1
34
18
19
3
9a
5
7
12
28
27
9b
4

3. - Identification of the machine
GMD24-GMD28 / HD
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KN226BGB_A
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Certification plate (CE)
For machines aimed at countries which are
members of the European Union (EC marking).
4: KUHN logo
7: Model
9: Machine serial number
19: Plate reference
23: Logo CE
24: Manufacturing year
26: Model year
54: Data matrix
Certification plate (EAC)
For machines aimed at countries member of the
Eurasian customs union (EAC marking).
4: KUHN logo
7: Model
9: Machine serial number
19: Plate reference
23: Logo EAC
25: Manufacturing year
26: Model year
54: Data matrix
Importer plate (BRASIL)
For machines to be sent to Brazil.
1: Manufacturer name and address
4: KUHN logo
7: Model
9: Machine serial number
19: Plate reference
24: Manufacturing year
54: Data matrix
24: Year of Construction
26: Model Year
7: Model
9: Serial Nr.
23
54
4
19
7
9
24
26
25: Month-Year of Construction
26: Model Year
7: Model
9: Serial Nr.
23
54
4
26
25
7
9
19
24: Year of Construction
19
54 4
1
24
97

GMD24-GMD28 / HD
10 3. - Identification of the machine
KN226BGB_A
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3.4 Optional equipment
- Tick box corresponding to the equipment fitted on
your machine:
GMD24 / HD
GMD28
GMD24-28 / HD
1 3/8’’ - 6 spline pto shaft (With free wheel clutch).
High cone disc kit.
Female coupler.
Raised skid shoes.
Inner swath disc.
Inner swath shield.
Anti-ridging plate.
Side deflector with high cone disk.
Frame connection arm/cutterbar.
Lighting and signalling.
Lateral signalling equipment (Only for France).
Lighting and signalling (Only for USA).
Auxiliary compensating spring.
Toolbox.
Wear skids.

4. - Safety
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4. Safety
4.1 Description of symbols used in
this document
This symbol indicates a potentially hazardous
situation that if not avoided, could result in serious
bodily injury.
This symbol is used to identify special instructionsor
procedures which, if not followed strictly, could
result in machinery damage.
This symbol is used to communicate technical
information of particular interest.

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12 4. - Safety
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4.2 Safety instructions
4.2.1 Introduction
The machine must only be operated, maintained
and repaired by competent persons who are familiar
with machines' specifications and operation and
aware of safety regulations for preventing
accidents.
The operator must imperatively respect safety
instructions in this manual and in the warnings
posted on the machine. The operator is also obliged
to respect current legislation concerning accident
prevention, work safety and public traffic circulation.
Designated use of the machine also means
following operation, maintenance and repair
recommendations given by the manufacturer, and
using only genuine spare parts, equipment and
accessories, as recommended by the manufacturer.
The manufacturer is not held liable for any damage
resulting from machine applications other than
those specified by the manufacturer. Any use other
than the designated operation is at the risk and
responsibility of the operator.
The manufacturer is not held liable for any damage
or accident resulting from machine modifications
carried out by the operator himself or by a third party
without previous written agreement from the
manufacturer.
4.2.2 Read and follow the safety instructions
- Before using the machine, carefully read all the
safety instructions in this manual and the warnings
placed on the machine.
- Before starting work, the operator must be familiar
with all machine controls, handling devices and
their functions. It is too late to learn once work has
been started!
- Never let anyone operate the machine who is not
trained to do so.
- Should you have any difficulties in understanding
any parts of this manual, please contact your
KUHN dealer.

4. - Safety
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4.2.3 Precautions to be taken before carrying
out any operations on the machine
- Before leaving the tractor or before adjusting,
maintaining or repairing the machine, disengage
the PTO drive, turn off the engine, remove ignition
key and wait until all moving parts have come to a
complete stop and apply park brake.
4.2.4 Precautions to take before using the
machine
- Do not wear loose clothing which could become
caught up in moving parts.
- Wear the appropriate protective clothing for the
work in hand (gloves, shoes, goggles, helmet, ear
defenders, etc.).
- Ensure that all operating controls (ropes, cables,
rods, etc) are placed so as they cannot be
operated unintentionally and cause damage or
injury.
- Before operating the machine, check tightness of
nuts and bolts, particularly on fixing elements
(tines, forks, blades, knives, etc). Retighten if
necessary.
- Before operating the machine, ensure that all the
safety guards are firmly in place and in good
condition. Immediately replace any worn or
damaged guard.

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14 4. - Safety
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4.2.5 Precautions when coupling
- Before attaching the machine, make sure that it
cannot accidentally start moving (chock the
wheels) and that the parking stand is in the right
position.
The machine must only be attached to the hitch
points provided for this purpose.
- Never stand between the tractor and the machine
when operating the three point linkage.
- Do not stand between the machine and the tractor
or on the machine without having first applied the
tractor parking brake andplaced the gearbox in the
neutral position.
4.2.6 Precautions when driving
Tractor handling, stability, performance and braking
efficiency are all affected by weight distribution,
trailed or mounted implements, additional ballast
and driving conditions. It is therefore of great
importance that the operator exercises caution in
every given situation.
- Groundspeed must be adapted to ground
conditions as well as to roads and paths. Always
avoid abrupt changes of direction.
- Be particularly cautious when turning corners,
paying attention to machine overhang, length,
height and weight.
- Never use a narrow track tractor on very uneven or
steeply sloping ground.
- Never leave the tractor seat while the machine is
operating.
- Carrying people or animals on the machine when
working or in transport is strictly forbidden.

4. - Safety
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4.2.7 Hydraulic circuit
Caution! The hydraulic circuit is under high
pressure. Maximum pressure at work: 200
bar (2901 psi).
Before connecting hoses to the tractor hydraulics,
ensure that tractor and machine circuits are not
under pressure. Before disconnecting a hose,
depressurize the hydraulic circuit.
To avoid making incorrect connections, mark
hydraulic couplers and corresponding hoses with
colors. WARNING! Functions could be reversed (for
example: lift/lower) and cause accidents.
- Regularly make visual inspection to check if
hydraulic hoses are damaged or worn. In case of
normal wear, the hydraulic hoses must be
replaced every 5 years. Damaged or worn hoses
must immediately be replaced. When replacing the
hydraulic hoses, only use hoses with the
specificationrecommendedby the manufacturerof
the machine.
- To locate a leak, use appropriate means. Protect
body and hands from liquid under pressure.
Any liquid under pressure (particularly oil from
hydraulics) can penetrate the skin and cause severe
injury. If injured, see a doctor immediately, there
could be danger of infection.
- Before any adjustments, maintenance or repairs
are carried out, lower the machine to the ground,
depressurize the hydraulics, turn off the engine,
remove ignition key and wait until all moving parts
have come to a complete stop.
4.2.8 Precautions when driving on public
roads
Dimensions
- Depending on the dimensions of the machine,
contact the relevant authorities to ensure that it
can be legally transported on public roads.
- If the machine is over the maximum legal size,
follow the local regulations for special
transportation of oversize equipment.
Transport position
- Before transporting the machine on public roads,
place the machine into its transport position,
according to the instructions in this manual.

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16 4. - Safety
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Lights and indicators
- Before transporting the machine on public roads,
ensure that all legally required lightings and
signallings are in place.
- Ensure that lightings and signallings are clean and
in good working order. Replace any missing or
broken equipment.
- Always obey current regulations for driving
on roads.
Gross weight and weight per axle
The drawings are not legally binding, their only
aim is to illustrate the method to use.
- Prior to driving on public roads, check that
all criteria are met to be in conformity with
the countrie's regulations:
• When coupling a tool to the front and/or
rear 3-point lift linkage, the maximum
authorized payload must not be
exceeded.
• When coupling tools to the front and/or
rear 3-point lift linkages, the maximum
load on tractor's tires must not be
exceeded.
• The load on the tractor front axle must
always represent 20 % of the tractor
unladen weight.
For machines with hoppers or tanks:
- If the total unit weight exceeds the tractor
Gross Combined Weight Rating in
accordance with the countrie's legislation,
empty the hopper to travel on public roads:
• In any case, we recommend to travel on
public roads with empty hoppers and
tanks.

4. - Safety
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Description of symbols:
Description Units Description
T kg Tractor unladen weight
PTAC kg Gross Combined Weight Rating
T1 kg Unladen load on tractor front axle
T2 kg Empty load on tractor rear axle
t kg Axle loads (Tractor + machine)
t1 kg Load on front axle (Tractor + machine)
t2 kg Load on rear axle (Tractor + machine)
t1 max kg Maximum load authorized on the tractor front axle according to the tires
t2 max kg Maximum load authorized on the tractor rear axle according to the tires
M1 kg Total weight of front tool or front ballast
How to proceed:
• Stage 1:
To measure:
• Tractor tare (T).
T = _____kg
T = ________ kg

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18 4. - Safety
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• Stage 2:
- Couple the machine to the tractor.
To measure:
• Load on front axle (t1):
• Tractor + machine (transport position).
To do:
- If the front axle load (t1) is below 20% of the tractor
tare (T), add ballast weights (M1) to exceed the
minimum load on the front axle.
Example:
• (T) = 7500 kg (16535 lb).
• 20% of T = 1500 kg (3300 lb).
• (t1) = 700 kg (1545 lb).
• 700 kg (1545 lb) < 1500 kg (3300 lb).
• Add ballast weights until the minimum front axle
load is exceeded.
- Repeat checking procedure.
• Stage 3:
To measure:
• Total weight (t):
• Tractor + machine (transport position).
• Ballast weights.
Checking:
• To go to the next stage:
- Check in the tractor's operator's manual that the
value measured is below the tractor's Gross
Combined Weight Rating.
To do:
• If t < PTAC go to the next stage.
• If the total unit weight exceeds the tractor Gross
Combined Weight Rating in accordance with the
countrie's legislation, empty the hopper to travel
on public roads.
Example:
• (t) = 10000 kg (22046 lb).
• PTAC = 13000 kg (28660 lb).
• t < PTAC : Go to the next stage.
t1 = _____kg
t1 = ________ kg
t1 < 20% Tt1 < 20% T
t1t1 ≥20% T20% T
kgkg
t = _____kg
t = ________ kg

4. - Safety
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• Stage 4:
To measure:
• Load on rear axle (t2):
• Tractor + machine (transport position).
• Ballast weights.
Checking:
- Check in the tractor's operator's manual that the
value measured is below the maximum allowed
tractor rear axle load.
- Check that tyre and rim specifiations are in
conformity with the requirements of the tractor
manufacturer.
Example:
• Load on rear axle (t2) = 8500 kg (18740 lb).
- Check in the tractor's operator's manual that the
value measured is below the maximum allowed
tractor rear axle load.
- Check that tyre and rim specifiations are in
conformity with the requirements of the tractor
manufacturer.
4.2.9 Maximum speed
- Always keep to the legal speed limit for driving a
tractor-machine assembly on public roads.
4.2.10 PTO shaft
- Use only PTO shafts supplied with the machine or
recommended by the machine manufacturer.
- The protective shield of the tractor PTO stub, the
PTO shaft guards and the protective shield of the
machine input shaft must always be in place and in
good condition.
- Make sure that the PTO shaft guards are secured
with the safety chains provided. Check that the
PTO shaft guard can turn freely a full rotation
independent of the shaft.
- Any worn or damaged guards must be replaced
immediately. A worn guard or an unprotected PTO
shaftcan causea seriousor evena lethalaccident.
kgkg
t2 = _____kg
t2 = ________ kg
t2 > t2 maxt2 > t2 max
t2t2 ≤t2 maxt2 max

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- Do not wear loose clothing that could be caught in
the rotating PTO shaft.
- Before attaching or removing a PTO shaft, or
before doing any work on the machine, disengage
the PTO drive, turn off the engine, remove ignition
key and wait for all moving parts to come to a
complete stop.
- If the primary PTO shaft is equipped with a torque
limiter or a free wheel, these must be fitted on the
machine side.
- Ensure that the PTO shaft is always correctly fitted
and locked into place.
- Before connecting the PTO shaft, ensure that the
PTO speed (rotational frequency) and direction of
rotation are in line with the machine manufacturer's
recommendations.
- Before engaging the PTO drive, make sure that
there are no people or animals near the machine.
Never engage the PTO drive when the tractor
engine is stopped.
- Do not install any adapter device that results in a
portion of the tractor PTO stub, the rotating PTO
shaft, or the adapter to be unguarded. The tractor
master shield shall overlap the end of the splined
shaft and the added adaptor device as outlined in
the table.
A