KUHN GMD 600 User manual

ASSEMBLY / OPERATOR'S MANUAL
GMD 600 - 700
MULTIDISC MOWER
N° 95002 B.GB - 02.97

DEAR OWNER,
In buying a KUHN machine you have chosen wisely. Into it have gone years o thought,
research and improvements. You will ind, as have thousands o owners all over the world, that
you have the best that engineering skill and actual ield testing can produce. You have
purchased a dependable machine, but only by proper care and operation can you expect to
receive the per ormance and long service built into it.
This manual contains all the necessary in ormation or you to receive ull e iciency rom your
machine. The per ormance you get rom this machine is largely dependant upon how well you
read and understand this manual and apply this knowledge. Please DO NOT ASSUME THAT
YOU KNOW HOW TO OPERATE AND MAINTAIN YOUR MACHINE be ore reading this
manual care ully. KEEP THIS MANUAL AVAILABLE FOR REFERENCE.
Your KUHN dealer will instruct you on the general operation o your machine. He is interested
that you get the best per ormance possible and will be glad to answer any special questions
that may arise regarding the operation o the KUHN machine.
Your KUHN dealer can o er a complete line o genuine KUHN service parts.
These parts are manu actured and care ully inspected in the same actory that builds the
machine to assure high quality and accurate itting o any necessary replacements.
When ordering service parts it is important that you indicate the type o machine concerned
and its serial number.
For this reason please complete the model identi ication plate diagram below with the required
in ormation. This will provide you with an easy re erence or uture service parts orders.
ABOUT IMPROVEMENTS
KUHN is continually striving to improve its products and, there ore, reserves 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.

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CONTENTS
Page
Safety 2
Safety decals 8
Technical specifications 10
Assembly 11
General information 17
Adapting to the tractor 18
P.T. . shaft 20
Transport 21
Working position and adjustments 22
Cutting height 23
Safety breakaway 24
Parking the machine 25
perating the mower 26
Lubrication 27
Adjustments and maintenance 28
Inspection of knives & securing elements 32
ptional equipment 34
Trouble shooting guide 38
Storing the mower 39
Limited warranty 40
Copyright 1997 KUHN S.A.

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SAFETY
The symbol above is used throughout this manual every time recommendations are made concerning your safety,
the safety of others, or the good operation of the machine.
These recommendations must be made known to all machine operators.
DESIGNATED USE OF THE MACHINE
GMD 600 - 700 Disc Mowers must only be used for the work which they have been designed : mowing on the ground
of hay fields, grass silage fields and improved pastures for the purpose of harvesting fodder for feeding livestock.
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.
Designated use of the machine also means :
- following operation, maintenance and repair recommendations given by the manufacturer ;
- using only genuine spare parts, equipment and accessories as designated by the manufacturer.
GMD 600 - 700 Disc Mowers must only be operated, maintained and repaired by competent persons who are familiar
with machine specifications and operation and are aware of any danger involved.
The operator must imperatively respect current legislation concerning :
- accident prevention,
- work safety,
- public traffic circulation.
All safety advice indicated on the machine must be strictly observed.
The manufacturer is not held liable for any damage resulting from machine modifications carried out by the operator
himself or by a third party without previous written agreement from the manufacturer.

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6. Use a tractor equipped with a safety cab. Keep windows and roof hatch closed for reduced sound level while
operating the PT driven implement.
7. Before starting up the machine and beginning work, check the surrounding area (beware of children !). Make
sure there is sufficient visibility. Keep all people and animals away from the danger zone of the machine (risk
of projection!).
8. Carrying people or animals on the machine when working or in transport is strictly forbidden.
9. Machine must only be attached to tractor using means provided and in accordance with current safety
standards.
10. When attaching or removing the machine, place the parking stand into the corresponding position.
11. Special care should be taken when attaching or removing the machine from the tractor.
12. Before attaching the machine, ensure that the front tractor axle is sufficiently ballasted.
Ballast is to be placed on the supports provided in accordance with instructions of the tractor manufacturer.
13. Do not surpass the maximum axle load or the overall transport weight as prescribed by the tractor manufacturer.
14. Do not surpass the maximum transport width authorized by road traffic regulations.
15. Before transporting the machine on public roads, ensure that all legally required guards and indicators (lights,
reflectors ...) are in place and in good operation.
16. All operating controls (cords, cables, rods ...) must be positioned so that they cannot be set off accidently,
risking accident or damage.
17. Before transport on public roads, locate the machine into its transport position as instructed in this operators
manual.
18. Never leave the tractor seat while the machine is operating.
GENERAL SAFETY RECOMMENDATIONS
Before operating the machine, always ensure that tractor and machine are in accordance with work safety and road
traffic regulations.
BASIC PRINCIPLES
1. In addition to the recommendations given in this manual, legislation on work safety and accident prevention
must also be respected.
2. Advice is indicated on the machine, specifying safety recommendations in order to prevent accidents.
3. Before travelling on public roads, the operator must ensure that the machine conforms to road traffic regulations.
4. Before starting work, the operator must be familiar with all machine controls, handling devices and their
functions. nce at work, it is too late to do so !
5. Do not wear loose clothing which could become caught up in moving elements.

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19. Drive speed must be adapted to ground conditions as well as roads and paths.
Always avoid abrupt changes of direction.
20. Precision steering, tractor adherence, road holding and efficient braking are influenced by the type of
implement, weight, ballast of front axle, ground or road conditions. It is therefore of utmost importance to be
cautious in every given situation.
21. Be particularly cautious when turning corners, paying attention to machine overhang, length, height and weight.
22. Before operating the machine, ensure that all safety guards are firmly in place and in good condition. If worn
or damaged, replace immediately.
23. Before operating the machine, check tightness of nuts and bolts, particularly on tool fixing elements (blades,
tines, knives, spades ...). Retighten if necessary.
24. Keep clear of the machine operating area.
25. WARNING ! Danger of crushing and shearing can exist when components are operated by hydraulic or
pneumatic controls.
26. Before leaving the tractor or before adjusting, maintaining or repairing the machine, turn off the engine, remove
ignition key and wait until all moving parts have come to a complete stop.
27. Do not stand between the tractor and the machine unless the hand brake is tight and/or stops have been placed
under the wheels.
28. Before any adjustments, maintenance or repairs are carried out, ensure that the machine cannot be started
up accidentally.
ATTACHMENT
1. When attaching or removing the machine from the tractor, position hydraulic lift control lever in such a way that
it cannot be set off accidentally.
2. When attaching the machine to tractor 3-point linkage, ensure that diameter of link pins corresponds to diameter
of ball joints.
3. WARNING ! Danger of crushing and shearing can exist in the lifting zone of the 3-point linkage !
4. Do not stand between the tractor and the machine when operating the outer control lever of the lift mechanism.
5. In transport, the machine lift mechanism should be stabilized by tractor tie rods to avoid floatation and side
shifting.
6. When transporting the machine in the raised position, lock the lift control lever in place.
7. Do not operate the machine with narrow wheeltrack tractors when working or transporting on uneven or sloping
terrain.

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POWER TAKE-OFF
1. nly use PT shaft supplied with the machine or recommended by the manufacturer.
2. PT guards must always be in place and in good condition.
3. Check for correct PT overlap when at work and in transport.
4. Before attaching or removing the PT shaft, disengage PT shaft, turn off engine and remove ignition key.
5. If a primary PT shaft is equipped with a slip clutch or a free wheel, these must be fitted on the machine PT .
6. Ensure that PT shaft is always correctly fitted and locked into place.
7. Make sure guards are correctly in place and secured with the safety chains provided.
8. Before engaging PT , ensure that PT speed and direction are in accordance with manufacturer's recommen-
dations.
9. Before engaging PT , keep all people and animals clear from the machine.
10. Never engage PT shaft when tractor motor is turned off.
11. Never surpass PT angle recommended by the manufacturer.
12. WARNING ! Rotating elements can continue turning momentarily after PT is disengaged. Keep clear until all
rotating elements are at a standstill.
13. When removing the machine, locate PT shaft on the supports provided.
14. Fit safety cap on tractor PT .
15. Replace any worn or damaged PT guards immediately.
HYDRAULIC SYSTEM
1. WARNING ! Hydraulic system is under pressure.
2. When fitting hydraulic motors or cylinders, ensure that connections have been made correctly, as per
manufacturers instructions.
3. Before connecting hoses to the tractor hydraulics, ensure that tractor and machine circuits are not under
pressure.
4. It is strongly recommended that the operator marks the hydraulic connections between tractor and machine to
avoid making a wrong connection. WARNING ! Functions could be reversed (for example : lift/lower).

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5. Check hydraulic hoses regularly ! Worn or damaged hoses must be replaced immediately.
Replacement parts must be in accordance with manufacturers recommendations concerning specifications and
quality.
6. Should a leak be found, take all necessary precautions to avoid accidents.
7. 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.
8. Before any adjustments, maintenance or repairs are carried out, lower the machine, depressurize the circuit,
turn off the engine and remove ignition key.
MAINTENANCE
1. Before checking any machine malfunction and before adjusting, maintaining or repairing the machine, disengage
PT , turn off engine and remove ignition key.
2. Check tightness of nuts and bolts regularly. Retighten if necessary.
3. If the machine is raised, prop it up in a stable position before carrying out any maintenance work.
4. When replacing a working part, wear protection gloves and only use standardized tools.
5. It is forbidden to discard any oil, grease or filters. These must be given to waste disposal organisations to protect
the environment.
6. Disconnect power source before any work is done on the electric system.
7. Check safety guards regularly, particularly those that are subject to wear. Replace immediately if damaged.
8. Spare parts used must be in accordance with specifications and standards as defined by the manufacturer. Use
only genuine KUHN parts !
9. Before any electric welding is carried out on tractor or attached machine, disconnect generator and battery
terminals.
10.Repairs on elements under pressure or tension (springs, accumulators etc.) must only be carried out by
competent persons with standardized equipment.

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SPECIAL SAFETY RECOMMENDATIONS
1. Use a tractor equipped with an enclosed cab with windows made of safety glass and kept closed. It is
recommended to fit polycarbonate screens inside the tractor safety cab's side and rear windows or to install mesh
guards on the exterior of them.
2. Stay a safe distance away from the mower when discs are rotating.
3. For safe machine operation, it is imperative that cutting tools be fitted in accordance with the manufacturers
recommendations. Use only the tool outfit supplied with the machine.
4. Each time before using the mower, inspect condition of cutting elements (knives, discs). Replace any missing,
worn or damaged cutting elements immediately. Use only genuine KUHN spare parts.
5. To avoid creating dangerous out of balance forces, always replace missing, damaged or worn knives in pairs.
6. When replacing knives or discs, systematically inspect their securing elements as per the manufacturers
recommendations.
7. Regularly inspect the disc mowers protection cover. Worn or damaged protection covers must be replaced
immediately.
8. Protection devices (such as guards, shields etc.) are intended to prevent stones, rocks or other foreign objects
from being projected. They also prevent access to the machines danger zones. Therefore, it is imperative that
protection devices are put in place and properly secured each time before using the machine.
9. Crushing and shearing zones which could cause serious bodily injury when changing the machine from transport
to work position and vice versa may exist. To prevent possible injury, be extra careful when maneuvering and
ensure that everyone is at a safe distance away from the machine.
10.PT drive to the mower must never be engaged unless the cutterbar skid shoes are in contact with the ground
and the protective cover is folded down.
11.Ground of the pastures to be mown must be free of foreign objects.
12.Even when the machine is used in accordance with its purpose, objects may be projected. It is therefore
imperative that everyone be kept away from the danger zone, that extra care be taken and that extra precaution
(such as safety indicators) be taken when mowing pastures alongside roads or near public areas (parks, schools
etc.).
13.Never mow in reverse.
14.When disengaging the PT drive, moving parts continue to rotate for some time. Wait for all moving parts to come
to a complete stop before approaching the machine.
15.If an obstruction is hit, stop the tractor immediately, disengage PT drive, turn off engine, remove ignition key
and wait for all moving parts to come to a complete stop.
Check the entire machine for any damage before resuming work.
16.It is strongly recommended to have your machine checked by your dealer after each season, especially blades
and discs and their fixing devices (nuts, bolts etc.).

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SAFETY DECALS
THE F LL WING SAFETY PICT RIALS HAVE BEEN PLACED N Y UR MACHINE IN THE AREAS
INDICATED. THEY ARE INTENDED F R Y UR PERS NAL SAFETY AND F R THE SAFETY F THE
PE PLE W RKING WITH Y U. THE TEXT SH WN N THEM GIVES THEIR PRECISE MEANING.
KEEP THE PICT RIALS LEGIBLE. IF THEY ARE N T, REPLACE THEM.

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Number of discs 6 7
Width of cut 2.40 m / 7' 10" 2.80 m / 9' 2"
PT power requirement 30 kW (42 hp) 36 kW (50 hp)
P.T . speed 540 rpm 540 rpm
Disc speed 2986 rpm 2986 rpm
Width in transport position *0.23 m (9") wider than tractor width*
Lift system hydraulic hydraulic
Weight (approx.) 494 kg / 1086 lbs 527 kg / 1160 lbs
Bevel gearbox oil capacity
il quality : SAE 80 GL4 (EP)
Cutterbar oil capacity 2.00 l / 4.25 US pint
il quality : SAE 80 GL4 (EP) 3.5 Imp pint
* Applicable if machine is attached in such a way that a 5 cm / 2" distance "A" is respected (see page 18).
TYPE GMD 600 GMD 700
0.45 l / 1 US pint
0.75 Imp pint
TECHNICAL SPECIFICATIONS

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ASSEMBLY
To facilitate shipping of the GMD 600 and 700 disc mowers, certain parts or assemblies are partially disassembled
to reduce bulk. To assemble these parts proceed as follows :
1. Moun ing chassis o cu erbar
Make sure that the bore of nylon bushings is clean and well greased. Remove protective paint from the front cover
of bevel gearbox where bushings make contact. Chock chassis. Pull parking stand control lever (C) backwards and
swing it to the right (looking in the direction of travel). Attach chassis to cutterbar with 2 self-locking screws (B) ( M
16 x 50) and 2 washers (A) (dia. 16.5 x 60) as shown in photo 1 and figure 1. Torque : 30 daNm/220 ft.lbs.
Install compensating spring rod (N) in its housing ( ) (photo 1).
FOR YOUR SAFETY BE SURE TO CHOCK CHASSIS CORRECTLY.

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2. Fi ing he break-away la ch
Fit break-away latch (P) on headstock yoke (Q) and
main frame yoke (R) with 2 pins (S) and 4 roll pins (T)
(dia. 6 x 36) as shown in photo 2.
3. Assembly of bel shield and bel s
- Install the inner belt shield (D) (photo 3) in place and
secure with the 3 spacer bolts (E) taped on the stop
chain.
- Install closing plate (F) equipped with elastic nut as
shown in photo 3.

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- Install belts (G) (photo 3) on pulleys and tension
them by tightening screw (H) (photo 3 A).
- Belt tension is correct if deflection does not exceed
10 mm (2/5") when belt is pressed upon with a force
of 3.5 kg (8 lbs) at mid distance between pulleys.
- When correct tension has been obtained, tighten
lock nut (J) (photo 3 A).
- Attach outer belt shield (X) with 3 washers and 3 cap
nuts (I) (photo 4).
- Assemble closing plate and outer belt shield with
one self-locking screw (K) (M 8 x 16) (photo 4).
4. Frame pipe and lif bracke assembly
- After cleaning attach frame pipe (L) (photo 5) to bevel
gearbox with 4 screws (M) (M 16 x 40). (Torque : 21
daNm / 155 ft.lbs).

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- Attach lift bracket (N) (photo 6) using axle ( ) and
split pins (dia. 5 x 32) provided.
- Connect compensating spring (P) (photo 7) to axle
(R) of frame pipe and secure with 2 roll pins (dia.
8 x 40).
- Fit inner shoe (I) by means of 4 cup square bolts (J)
(M 10 x 25) and 4 self locking nuts (M 10) (photo 8).
5. Compensa ing spring, inner shoe and inner swa h board assembly

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- Attach inner swath board (S) (photo 8 a) in place with
3 cup square bolts (T) (M 10 x 20), 3 flat washers (dia.
11 x 24 x 2) and 3 self locking nuts (M 10).
Tighten all swath board bolts (T).
6. Ins alling ou er disc wi h cone and ou er swa h wheel
- Attach the outer disc with cone using 4 hexagon
screws (M 12 x 20) and 4 conical spring washers
(position the conical centre at the top) so that its
largest diameter is positioned at a right angle in
relation to the adjacent disc (see pictorial opposite).
Tight n at 12 daNm (90 ft.lbs).
- Attach swath wheel assembly (U) to outer skid shoe
(photo 9) with 2 cup square bolts (V) (M 12 x 35), 2
conical washers (dia. 13 mm) and 2 self-locking nuts
(M 12).
Torque : 8.5 daNm/65 ft.lbs
Before tightening screws (V), make sure that swath
wheel does not come into contact with cone cover or
knives.
Keep to a distance of X = 15 to 25 mm / 3/5" - 1".
The angular position of the swath wheel compared to the cutterbar can be adapted to working conditions
enabling a regular flow of the cut crop towards the rear.
Position the swath wheel so that maximum angl (A') (fig. 9 A) is obtained. In difficult working
conditions (long, dense, bent over crops) position it towards minimum angl (A) (fig. 9 A).

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7. Safe y guard and locking device assembly
- Attach the front safety bar (B) to its 3 hinges (C) with
the 5 cup square bolts (P) (M 10 x 25) and 5 self-
locking nuts ( ) (M 10) (fig. 10).
- Then attach the pre-assembled front safety bar (B)
at (N) with 3 hexagonal screws (M 12 x 75) and self-
locking nuts (M 12) (photo 11). Do not tighten these
3 screws completely, so that the front safety bar can
still pivot.
- Next attach rear safety bar (A) with 5 round head
bolts (P) (M 10 x 25) and 5 self-locking nuts ( )
(M 10) (fig. 10 and photo 11). Fit nd-plug (Z) on
r ar saf ty bar (A) (photo 11).

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1. Minimum tractor power used should be 31 kW
(42 PT hp) for the GMD 600 and 37 kW (50 PT
hp) for the GMD 700. If tractor power is not suffi-
cient, quality of work will not be satisfactory.
2. GMD 600 and GMD 700 disc mowers can be
adapted to all tractors having a PT speed of 540
rpm and equipped with a normalized Cat. 2 three
point hitch.
3. GMD 600 and GMD 700 are equipped with adjust-
able lower hitch pins allowing the machine to be
offset 50 mm (2") to the left and 50 mm (2") to the
right.
4. To adjust lower hitch pins (T) (photo 14), loosen the
4 hexagonal screws (U) of collar flanges (V) on each
side. Reposition lower hitch pins respecting dimen-
sion 825 mm (28") (page 18) and retighten screws
(U). Torque : 12 daNm/88 ft.lbs.
Ch ck tight n ss of scr ws (U) aft r t n hours
of us .
GENERAL INFORMATION
- Install cover (D) as shown in photo 12. Buckle straps around the pipe frame at E. Buckle straps (F) around front
and rear safety bar. All these straps are attached to the underneath of the safety cover.
- Punch 3 holes in the safety cover at (G) and use 3 cup square bolts (R) (M 10 x 35) with self-locking nuts (0) (M
10) (fig 9) and plain washers (Q) (dia. 11 x 24 x 2) to attach the following components on the outside arms of the
safety bars : safety guard locking device (S) ; safety cover (D) ; stop rod (J) (see fig. 10 and also refer to photos
11, 12 and 12 A).
Not : Make sure that the pivot axis of the safety guard locking device (S) is lined up with the pivot axis (N) of the
front safety bar before tightening self-locking nuts ( ).
CAUTION : ALWAYS OPERATE MOWER WITH SAFETY COVER IN PLACE AND THE
FRONT END OF THE COVER LOWERED. NEVER LEAN AGAINST OR STAND ON
SAFETY COVER.
The safety guard locking device is operated with an
18mm box spanner (T) to be stored in holder (U) (photo
13).

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ADAPTING TO TRACTOR
A achmen of lower links and
posi ionning of hi ch pins :
Follow fig. 1 for category 2 tractors with narrow wheel
track.
Follow fig. 2 for category 2 tractors with standard
wheel track.
Follow fig. 3 for category 2 tractors with wide wheel
track.
Follow fig. 4 for Cat. 2 tractors with very wide wheel
track. In this case a lengthened left hitch pin for up to
200 mm (8") offset is required (see optional accesso-
ries on page 35).
NOTE : Always attach machine in such a way that
distance (A) is approximately 50 mm (2").