Kuhn GMD 240 / 280 / 310 service schedule

1. Lower the mower flat on the ground, disengage the PTO, stop the tractor engine, take the key out and apply the parking brake.
2. Wait until every disc has stopped turning. The discs run on for some time after the PTO is off: never lift a guard or reach in until they are still.
3. Wear gloves. Lift the front guard and check each knife.
4. Replace a knife that is cracked, bent or worn: length under 65 mm, width under 34 mm measured 10 mm from the disc, or less than 9 mm left beside the hole. Never straighten a bent knife.
5. Always change both knives on a disc together.
6. Replace the knife bolt if it is distorted, its locking compound is worn, its head is worn to the centre line, or its body is under 11 mm.
7. Replace the nut when it has worn by 5 mm.
8. Tighten knife bolts to 12.3 daNm (123 Nm), and recheck the bolts regularly.
9. Check the skids and disc guards for wear. Kuhn offers weld-on wear skids for hard conditions and raised skid shoes for a higher cut.
10. Close all guards before starting the PTO again.

Tools: Torque wrench (to 123 Nm), Rule, Gloves, Kuhn knife-change tool if fitted

1. Put the mower in work position on the ground, disengage the PTO, stop the tractor engine and take the key out. Wait until the discs have stopped.
2. Clean the nipples, then grease the universal joints, the transmission tube, the guide rings and the freewheel.
3. Check the guard is complete, turns freely on the shaft and is chained at the machine end (hole 1). Replace a worn or split guard at once.
4. Check the shaft never runs at more than 30°.
5. After shortening a shaft, bevel and clean the tubes and grease the inside of the outer tube.

Tools: Grease gun, Rags

1. Run the mower for a few minutes first so the oil is warm and drains well, then lower it, disengage the PTO, stop the tractor engine and take the key out. Wait until the discs have stopped.
2. Raise it into transport position and make sure the transport lock is on. Never stand under the raised cutterbar unless it is locked or propped.
3. Put a tray under the drain plug (2). Remove the filler plug (1) and its washer, then the drain plug and its seal.
4. Let it drain until it stops dripping.
5. Clean and refit the drain plug with its washer (renew if needed).
6. Fill with the right amount of 80W-90 GL-5 through the filler opening. Never use SAE 90.
7. Lower the cutterbar flat on the ground and check the level: it should reach the lower edge of the filling hole. Refit the filler plug and washer.

Tools: Drain tray, Spanners, Funnel, Gloves

1. Run it for a few minutes to warm the oil, then disengage the PTO, stop the tractor engine and take the key out. Wait until the discs have stopped.
2. From transport position (transport lock on), remove the filler plug and washer, put a tray under the drain plug and remove it.
3. Let it drain completely.
4. Put the cutterbar horizontal and fill through the filler opening until the oil reaches the lower edge of the drain hole.
5. Refit both plugs with their washers.
6. Take out the breather plug, clean it, check it works and refit it with its seal.

Tools: Drain tray, Spanners, Funnel

1. Read through the operator's manual again.
2. Lower the mower to the ground, disengage the PTO, stop the tractor engine, take the key out and apply the parking brake. Wait until the discs have stopped.
3. Wipe the grease off the ram rods.
4. Check the knives and bolts and replace worn ones (see the knife task). Check all nuts and bolts are tight.
5. Check the belts and replace them as a full set if worn. Tension: tighten screw 1 until the spacer tube touches the leg and washer. On new belts give it 2 more turns, and recheck in the first hours.
6. With the cutterbar flat, check the cutterbar oil reaches the lower edge of the filling hole, and the angle gearbox oil reaches the lower edge of its hole. Clean the breather.
7. Grease the release sheath, the leg pin and the 3-point vertical pivot, and oil the pivots. After greasing the release sheath, check dimension L is 95 mm and the lock is engaged.
8. Grease the PTO shaft.
9. Check all guards and the protective covers are fitted and in good order.

Tools: 18 mm box spanner (supplied), Torque wrench, Grease gun, Rule

1. Lower the mower, disengage the PTO, stop the tractor engine and take the key out. Wait until the discs have stopped.
2. Clean the machine thoroughly.
3. Drain and refill the cutterbar and angle gearbox (see those tasks).
4. Grease the exposed ram rods.
5. Touch up damaged paint.
6. Inspect the knives and bolts and replace worn ones.
7. Release the belt tension.
8. Store it under cover, somewhere dry, with the cutterbar horizontal on the ground.

Tools: Pressure washer, Grease gun, Touch-up paint