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.
Disc mower GMD24-GMD28 / HD 2. Contents Dear Owner ........................3 Contents ..........................4 Identification of the machine..................7 Front view ............................7 Rear view ............................7 Identification of the machine ......................8 Optional equipment........................10 Safety..........................11 Description of symbols used in this document................11 Safety instructions .........................
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Disc mower GMD24-GMD28 / HD Machine specifications....................31 Description and glossary ....................... 31 5.1.1 Designated use of the machine..................31 Technical specifications ......................... 32 5.2.1 Designated parameters ....................32 Required equipment ........................33 5.3.1 PTO shaft ......................... 33 5.3.2 Cutter bar ......................... 33 Sound levels ..........................
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Disc mower GMD24-GMD28 / HD Inner swath shield .......................... 56 Side deflector ..........................57 Side deflector with high cone disk ....................57 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...
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 ...
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Disc mower GMD24-GMD28 / HD Certification plate (CE) For machines aimed at countries which are 26: Model Year members of the European Union (EC marking). 24: Year of Construction 7: Model KUHN logo 9: Serial Nr. Model Machine serial number...
Disc mower GMD24-GMD28 / HD 4. Safety 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 instructions or procedures which, if not followed strictly, could result in machinery damage.
Disc mower GMD24-GMD28 / HD 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 safety regulations preventing accidents. The operator must imperatively respect safety instructions in this manual and in the warnings posted on the machine.
Disc mower GMD24-GMD28 / HD 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.
Disc mower GMD24-GMD28 / HD 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.
Disc mower GMD24-GMD28 / HD 4.2.7 Hydraulic circuit Caution! The hydraulic circuit is under high pressure. Maximum pressure work: 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.
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Disc mower GMD24-GMD28 / HD 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.
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Disc mower GMD24-GMD28 / HD Description of symbols: Description Units Description Tractor unladen weight PTAC Gross Combined Weight Rating Unladen load on tractor front axle Empty load on tractor rear axle Axle loads (Tractor + machine) Load on front axle (Tractor + machine)
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Disc mower GMD24-GMD28 / HD • 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.
Disc mower GMD24-GMD28 / HD • Stage 4: To measure: • Load on rear axle (t2): • Tractor + machine (transport position). • Ballast weights. kg kg Checking: - Check in the tractor's operator's manual that the value measured is below the maximum allowed tractor rear axle load.
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Disc mower GMD24-GMD28 / HD - 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.
Disc mower GMD24-GMD28 / HD PTO type Diameter X splines A ±5 mm (0.20’’) 35 mm (1.378’’) 85 mm (3.35’’) 36 mm (1.42’’) 85 mm (3.35’’) 35 mm (1.378’’) 85 mm (3.35’’) 45 mm (1.772’’) 100 mm (4.00’’) 44 mm (1.732’’) 100 mm (4.00’’)
For your own safety and for correct machine operation, only use original manufacturer parts. - It is strongly recommended to have your machine checked by your Kuhn dealer after each season, especially tools and their attaching hardware. 4. - Safety...
Disc mower GMD24-GMD28 / HD 4.2.15 Projection of stones and foreign objects For driver safety, always use a tractor equipped with a cab. Keep the ground to mow free of foreign bodies. Avoid mowing on stony or rocky grounds. If...
Disc mower GMD24-GMD28 / HD 4.2.17 Precautions for machine use After each use, check the cutting tools (discs, knives) their attachment hardware accordance with the instructions given in the present manual. Immediately replace any worn, damaged or missing cutting tool or element. To do this, use the tool outfit supplied with the machine.
Disc mower GMD24-GMD28 / HD Location and description of safety decals on the machine 4.3.1 Location of safety decals K9A148CE 0 4. - Safety KN226BGB_A...
Disc mower GMD24-GMD28 / HD 4.3.2 Description of safety decals Operating instructions (1) - The operators' manual contains all the information necessary for using the machine safely. It is imperative to read and comply with all instructions. Working on the machine (2)
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Disc mower GMD24-GMD28 / HD Projections (3) - Stones and other debris projected by the moving parts can travel a long distance. The protection covers must always be in position and in good condition. Always stay at a safe distance from the machine.
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Disc mower GMD24-GMD28 / HD Rotating cutting tools (6) - Keep away from the mower knives all the time the engine is running, the PTO drive engaged and the moving parts have not come to a complete stop. ...
Road safety equipment and recommendations The road safety equipment is mounted in the factory or by your authorized Kuhn dealer according to current safety regulations. - Always keep to the legal speed limit for driving a tractor-machine assembly on public roads.
Disc mower GMD24-GMD28 / HD Incorrect use of the machine by the user 133996: Specific requirements for countries member of the Eurasian Economic Community (EAC marking): • 133998: Specific requirements for countries member of the Eurasian Economic Community (EAC marking).
Cutterbar 5.1.1 Designated use of the machine The GMD24-GMD28 / HD mowers must only be used for the purpose for which they were manufactured: mowing on the ground of arable meadows, seeded grassland and permanent meadows for the purpose of harvesting fodder for feeding livestock.
Disc mower GMD24-GMD28 / HD Technical specifications GMD 24 GMD 28 Attachment type 3 point, Category 2 Number of discs Working width 2.44 m (7’10’’) 2.80 m (9’02’’) Width in working position 4.26 m (13’11’’) 4.67 m (15’04’’) Height in working position 1.15 m (3’9’’)
Disc mower GMD24-GMD28 / HD • "HD" discs Sound levels Sound levels have been measured in accordance with the measuring methods as defined in: • NF EN ISO 4254-1 «Agricultural machinery - Safety - Part 1: General requirements». Weighted equivalent continuous acoustic pressure level at the driver's seat (closed cabin) L (A) eq: •...
Disc mower GMD24-GMD28 / HD 6. Putting into service Description of control elements The machine is fitted with a release cord operated from the tractor cab. The machine is supplied with an 18 mm box wrench (1) to carry out certain adjustment and maintenance tasks.
Disc mower GMD24-GMD28 / HD 6.2.2 Preparing the tractor - Check that the tractor's authorized gross weight as well as its lift capacity and maximum weight axle exceeded. See section: - Safety / Safety instructions / Precautions when driving on public roads.
Disc mower GMD24-GMD28 / HD Lateral adjustment of the lower linkage arms - Distribute the play on each side of the lift linkage. - Check that the stabilisers function properly (Adjustment, Locking/Unlocking). 6.2.3 Preparing the machine Linkage adjustment The machine adapts to tractors fitted with a 3 point linkage category 2.
Disc mower GMD24-GMD28 / HD 6.2.4 Coupling the machine - Lower the tractor three-point linkage. - Attach lower links to the hitch pins on either sides of the machine (a). - Secure each hitch pin with lynch pin (b). - Attach top link.
Disc mower GMD24-GMD28 / HD 6.2.5 Hydraulic connections - Connect the mowing unit lift cylinder to a single acting valve. 6.2.6 Electrical connection When optional equipment is used, follow specific procedures mentioned in the related section: • Optional equipment Lighting signalling.
Disc mower GMD24-GMD28 / HD 6.2.8 Primary PTO shaft Before using the machine for the first time: - Grease the transmission. - Check overlap of the u-joint drive shaft and adjust length if necessary to avoid any premature wear. The direction of rotation is shown on a decal.
Disc mower GMD24-GMD28 / HD Never operate the PTO shaft at an angle X exceeding 30°. To avoid serious accidents, the PTO drive shaft guards must be properly in place and fixed with the chains provided. - Attach PTO shaft guard using chain provided in order to prevent it from rotating.
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Disc mower GMD24-GMD28 / HD Hitch pin parallelism. From the working position: - Measure and adjust the height of the hitch pins until the same measure is obtained on each side: • A = B = 450 mm (1’6’’).
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Disc mower GMD24-GMD28 / HD Tractor not fitted with a hydraulic position control function: - Lower the tractor lift to obtain a distance of H = 450 mm (1’6’’) between the Hitch pin axis and the ground: • Insert hook (1) in check chain link corresponding to the required frame height and lock using roll pin (2).
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Disc mower GMD24-GMD28 / HD The safety breakback is reset by reversing (a). - If the safety breakback releases after reset, tighten screw (1) to increase spring washer compression. Basic adjustments: L= 94 mm (3.7’’). a = 4 times 2 washers.
Disc mower GMD24-GMD28 / HD 6.2.10 Uncoupling the machine - For tractors not fitted with a hydraulic position control function, unhook check chain. The machine must be uncoupled in working position. From the transport position: - Lift the machine with the tractor's three point linkage.
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Disc mower GMD24-GMD28 / HD - Press push-button (1) and lower parking stand (2) until push-button engages in position (3). - Lower the tractor three-point linkage to rest the machine on the ground. - Detach the top link from the machine end.
Disc mower GMD24-GMD28 / HD 7. Instructions for transport Before placing the machine into transport position: - Check that nobody is within the machine pivoting area. - If there is someone, make sure the person moves away. Putting the machine into...
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Disc mower GMD24-GMD28 / HD - Operate single acting transport/work position cylinder to place the mowing unit in transport position: • The machine automatically locks in transport position. The machine is in transport position. - Never engage the tractor PTO drive when the machine is in transport position.
Disc mower GMD24-GMD28 / HD Conformity with the road regulations - Before driving the machine on public roads, ensure that the machine complies with current highway code regulations. - Check that the retroreflective signalling equipment is clean before going on public roads.
Disc mower GMD24-GMD28 / HD 8. Instructions for work Before placing the machine in working position: - Check that nobody is within the machine pivoting area. - If there is someone, make sure the person moves away. Putting the machine into work...
Disc mower GMD24-GMD28 / HD - Pull handle (1) to unlock front guard. - Lower and lock front guard. The machine is in working position. During work, only use the tractor lift linkage to place the machine in headland turn position.
Disc mower GMD24-GMD28 / HD - Check cutting height. The maximum cutting height L1 = 80 mm (3.1’’) is obtained when the disks are parallel to the ground. The minimum height must not be below L2 = 30 mm (1.1’’).
Disc mower GMD24-GMD28 / HD - Check that there is still a play J equalling minimum 15 mm (0.59’’) between the shell, the cone rib and the swath wheel. Machine use - Before mowing and to reduce risks of projections, lower the front guard.
9. Optional equipment 1 3/8’’ - 6 spline pto shaft (With free wheel clutch) Only for GMD24 / HD: A specific pto shaft is available as option for tractors equipped with a 1 3/8’’ - 6 spline pto stub. Female coupler...
The inner swath shield allows reducing the swath width to approximately 1.20 m (3’11’’) depending on the forage density. Only for GMD24 - GMD24HD: The inner swath shield must always be used in combination with the inner swath disk. Only for GMD28 - GMD28HD:...
Disc mower GMD24-GMD28 / HD Side deflector The side deflectors enables mowing dense or down crops with long stems. - Fit side deflector on the outer side plates of the cutterbar stiffener. Side deflector with high cone disk Large cone discs allow mowing dense or down crops with long stems.
Disc mower GMD24-GMD28 / HD 9.10 Lighting and signalling The machine can be fitted with specific signalling lights to comply with the road regulations. 9.10.1 Electrical connection - Connect machine 7-pin plug on the tractor 7-pin socket. - After making the connections, check that there is no risk of the hoses being caught during operation.
Disc mower GMD24-GMD28 / HD 9.12 Lighting and signalling (Only for USA) The machine can be fitted with specific signalling lights to comply with the road regulations. 9.12.1 Electrical connection - Connect machine 7-pin plug on the tractor 7-pin socket.
Disc mower GMD24-GMD28 / HD 9.14 Toolbox This equipment allows storing the tools, knives, bolts and nuts necessary for the machine maintenance. 9.15 Wear skids Wear skids can be welded underneath the disk guard to improve its resistance to wear in difficult working conditions.
Disc mower GMD24-GMD28 / HD 10. Maintenance and storage - Before adjusting, maintaining or repairing the machine, turn off ignition key and wait until all moving parts have come to a complete stop. 10.1 Frequency chart Maintenance intervals are indicated for normal conditions of use.
Disc mower GMD24-GMD28 / HD Lubrication Grease: • Primary PTO shaft. Oil change: • The cutterbar. • The side angle gearbox. Oil: • The moving parts and pivot points. 10.2 Lubrication The pictorials show the points to be greased.
Disc mower GMD24-GMD28 / HD 10.2.1 PTO shafts Primary PTO shaft - Place the machine in working position. - Stop the tractor engine and remove ignition key. Before using the machine for the first time: - Grease the transmission.
Disc mower GMD24-GMD28 / HD 10.2.2 Draining The cutterbar - Before draining oil, operate the machine for a few minutes so that the oil warms up. Oil and lubricants specifications GMD24 GMD28 Oil volume 2.00 L (0.53 US gal)
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Disc mower GMD24-GMD28 / HD - Never use an oil of viscosity SAE 90 in the cutterbar. From the transport position: - For safety reasons, hook check chain as high as possible. - Place a container of sufficient capacity under drain plug.
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Disc mower GMD24-GMD28 / HD The side angle gearbox - Before draining oil, operate the machine for a few minutes so that the oil warms up. Oil and lubricants specifications GMD24 GMD28 Oil volume 0.45 L (0.12 US gal)
Disc mower GMD24-GMD28 / HD Checking oil level of the lateral bevel gearbox: - Place the cutterbar in horizontal position: • The oil level must reach the lower edge of the emptying hole. - Clean and reinstall drain plug (2) and its washer.
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Disc mower GMD24-GMD28 / HD Checking the tension - Press belt using a force of 3.5 daN (7.9 lbf): • The belt should not deflect more than H = 10 mm (0.39’’). Adjusting the tension - Unscrew the 2 nuts (1).
Disc mower GMD24-GMD28 / HD 10.3.2 Breather plug checking and cleaning From the working position: - Remove breather plug (1). - Clean and check breather plug for good functioning (1). - Reinstall breather plug (1). 10.3.3 Checking cutterbar oil level...
Disc mower GMD24-GMD28 / HD If it is found that the transmission case is very hot to touch by hand, there is no cause of alarm provided: • Lubrication recommendations have been respected. • Discs can be rotated freely by hand when the machine is hot.
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Disc mower GMD24-GMD28 / HD Knives - Inspect systematically all knives before the machine is operated to: • ensure the cutting quality. • ensure safety in use. • Prevent cutterbar damage risks. - Replace knives in the following cases: •...
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Disc mower GMD24-GMD28 / HD Securing elements - Check the condition of the securing elements regularly and also the torque of the knife-fixing bolt: • Torque: 12 daNm (89 lbf ft). - Check the securing elements: • After hitting an obstacle.
Disc mower GMD24-GMD28 / HD 10.3.5 Knife replacement - Replace knife lock-nuts and bolts when they have been removed 5 times. - Replace immediately all worn or distorted knives. Never straighten a bent knife. - Always replace both knives per disc.
GMD24-GMD28 / HD 10.3.6 Disc replacement Inner disc The replacement of the inner disk must be carried out by your Kuhn authorized dealer. Intermediate discs - Place a wooden wedge (2) between two discs to stop them from moving.
Disc mower GMD24-GMD28 / HD - Check if there is still a minimum gap X = 1 mm (0.04’’) between the disk lower part and the cutter bar wear plates(c). - If this is not the case, fit one (maximum two) spacer(s) between the disc and the mounting hub (d).
Disc mower GMD24-GMD28 / HD 10.4 Storage 10.4.1 At the end of each season - Clean the machine thoroughly. - Drain all gearboxes and cutterbar and refill with new oil. - Grease the cylinder rods in contact with the outside.
Disc mower GMD24-GMD28 / HD 10.4.3 Storage • 139884: Specific requirements for countries member of the Eurasian Economic Community (EAC marking). • 139885: Specific requirements for countries member of the Eurasian Economic Community (EAC marking). • 139886: Specific requirements for countries member of the Eurasian Economic Community (EAC marking).
Disc mower GMD24-GMD28 / HD 11. Troubleshooting guide Problem Cause Remedy Dull or broken knives. Replace knives. Make sure the arrow on Knives not installed the knife upper face is correctly. pointing in the disc's Uneven stubble.
Disc mower GMD24-GMD28 / HD 12. Appendix 12.1 Calculating the load on an axle 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.
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Disc mower GMD24-GMD28 / HD Obtained Description Units Description Tractor unladen weight Unladen load on tractor front axle Empty load on tractor rear axle Axle loads (Tractor + machine) Load on front axle (Tractor + machine) Load on rear axle (Tractor + machine)
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Disc mower GMD24-GMD28 / HD Front tool: 1) Calculation of the minimum front ballast weight M2 minimum a T2 b – 0 45 ---------------------------------------------------------------------------- - M2minimum minimum - Write the minimal additional weight in the chart.
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Disc mower GMD24-GMD28 / HD Table Actual value obtained Value authorized Double value of the by calculation according to authorized capacity operator's manual per tyre (2 tyres) Minimum front/rear ballasting Total weight < Load on front axle < <...
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Disc mower GMD24-GMD28 / HD T2: Load on rear axle. • Tractor only. T2 = _____kg T2 = ________ kg T: Axle loads. • Tractor only. T = _____kg T = ________ kg Rear tool or front-rear combination - If the total unit weight exceeds the tractor...
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Disc mower GMD24-GMD28 / HD Front tool - If the total unit weight exceeds the tractor Gross Combined Weight Rating 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.
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Disc mower GMD24-GMD28 / HD t: Axle loads. • Tractor + machine. t = _____kg t = ________ kg Calculating the front tool weight: • M1 = t - T Calculating the distance (a): • a = ( b x ( T2 - t2) ) / M1 12.
KUHN equipment from an authorized KUHN dealer, that such equipment is, at the time of delivery to such purchaser, free from defects in material and workmanship, and that such equipment is covered under this Limited Warranty providing the machine is used and serviced in accordance with the recommendations in the Operator's manual.
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- The warranty claim is completed on line via extranet - www.kuhn.com or submitted on a KUHN warranty claim form and returned to the Company within one month after the date of failure or the date of problem becoming apparent.
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$Specimen of the "Declaration of conformity" EC Declaration of conformity (European directive 2006/42/CE) The manufacturer: Manufacturer name and address declares that the product described hereafter: Brand Brand Machine Machine Type / Model : Type / Model Serial no. Serial no. - conforms to the requirements of the European directive 2006/42/CE.
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KUHN S.A. - B.P. 50060 - F - 67706 SAVERNE CEDEX (FRANCE) KUHN-AUDUREAU SAS - B.P. 19 - F - 85260 LA COPECHAGNIERE (FRANCE) KUHN-BLANCHARD SAS - 24, route de Nantes - F - 44680 CHEMERE (FRANCE) KUHN-HUARD SAS - B.P. 49 - F - 44142 CHATEAUBRIANT CEDEX (FRANCE) KUHN-GELDROP B.V.
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