McHale 998 high-speed square bale wrapper service schedule

1. Change the hydraulic filter element as in the filter task.
2. Drain and refill the pump gearbox as in the pump gearbox task.
3. Drain and refill the dispenser drive gearbox, filling to half way up the sight glass.

Tools: Drain trays, Spanners, Clean rags, Funnel

1. Remove the three M10 setscrews from the top of the filter housing. It is under spring pressure, so press down as you undo them.
2. Lift off the housing top and the spring.
3. Lift the filter out. The pressed steel housing comes up with it and must be separated, leaving the housing in the tank. The bypass valve on top of the filter goes with the old one.
4. Fit the new filter into the housing so it is secure.
5. Refit the top with its O-ring correctly seated and tighten the three setscrews.
6. Run the machine and check everything works with no leaks.

Tools: Socket for M10 setscrews, Drain tray, Clean rags

1. Park on level ground with the wrapper switched off and not under pressure. Tilt it slightly so the tank slopes to the drain plug if needed.
2. Warm oil drains best. Put the container under the tank and remove the drain plug.
3. Change the filter element while the oil is draining (see the filter task).
4. Refit the drain plug and refill the tank through the filler until the oil is at the top mark on the sight gauge (about 130 L).
5. Run every function to clear air. You may need to prime the pump: loosen the top rear pressure pipe and turn the pump by hand until oil flows without air, then tighten.
6. Stop, let the oil settle, check the level between the sight gauge limits and top up.

Tools: Large drain container (130 L), Spanners, Funnel, Clean rags

1. Stop the tractor, apply the handbrake and remove the key.
2. Grease the points listed above with the service manual's grease. The service manual counts the nipples: drawbar cylinder ends 2, lifting cylinder ends 8, roller cradle pivots 4, cut and hold plunger 2, rear of front conveyor 2, front of main conveyor 3, rear of main conveyor 4, rear unloading roller 2, PTO cover 2.
3. Check tyre pressure (1.75 bar) and wheel nuts.

Tools: Grease gun, Clean rags

1. Grease the dispenser top roll holder shaft and bale position arm bearings.
2. Check the brake unit oil at the sight glass.
3. Measure chain sag at the middle of each chain between sprockets with one side tight. Main conveyor chain 25 to 30 mm, front pick-up chains 10 to 15 mm, roller drive motor chain 10 to 12 mm. Other drive chains are adjusted to the same kind of sag; follow the adjuster steps in the handbook.
4. Tighten the lock nuts after adjusting and refit the chain guards.

Tools: Grease gun, Spanners, Ruler for chain sag

1. Warm the gearbox oil so it drains easily. Put a container under the drain stud.
2. Take off the filler/breather cap, then remove the drain stud and let the oil drain.
3. Refit the drain stud and dispose of the oil safely.
4. Fill with EP80 gear oil until oil shows on the sight gauge.
5. Refit the cap, run the machine for 2 to 3 minutes, stop, let it settle, check the level again and top up.

Tools: Drain container, Spanner, Funnel, Clean rags

1. Stop the tractor, apply the handbrake and remove the key.
2. Drain the old oil from each unit.
3. Refill through the breather cap hole until the oil is half way up the sight glass.
4. Check for leaks after a short run.

Tools: Drain container, Spanner, Clean rags

1. Stop the tractor, apply the handbrake and remove the key. Wear protective gloves.
2. Release the two M6 setscrews that hold the knife clamp.
3. Remove the working knife. The spare is held at the bottom of the clamp.
4. Put the spare in the working position and fit a new spare underneath if you have one.
5. Tighten the two M6 setscrews.

Tools: Spanner for the M6 setscrews, Cut-resistant gloves

1. Clean the dispenser rollers with kerosene, wipe them dry and check they spin freely. A rubbing roller tears film.
2. Clean and re-lubricate the dispenser gears.
3. Check each trip arm turns freely. Strip and grease the pivots if not.
4. Replace a bent arm or a damaged cover.

Tools: Kerosene or diesel and rags, Grease brush, Spanners

1. Open the chain guards, release the tension and remove the front conveyor chains.
2. Clean them thoroughly and blow dry.
3. Soak them in oil, let them drain, refit and re-tension to 10 to 15 mm sag.

Tools: Spanners, Chain breaker or master link pliers, Parts-washer or diesel and a brush, Tray of oil

1. Clean the wrapper inside and out. If you use a pressure washer, keep it away from electrics, pivots, valves and bearings. McHale prefers an air line.
2. Remove the electronic control box from the tractor and store it somewhere dry.
3. Lubricate all pivot points and put a thin layer of grease on adjustment bolt threads and exposed ram rods.
4. Touch up worn paint or coat with grease. Blow all chains clean and dry.

Tools: Air line, Grease gun, Touch-up paint, Rags

1. Lubricate all pivot points and check the dispenser gearbox level at the sight glass.
2. Tighten bolts to the torque table in the manual. For example 8.8 bolts: M8 23 Nm, M10 45 Nm, M12 78 Nm, M16 195 Nm.
3. Check both tyres at 1.75 bar (26 psi).
4. Connect the control box and test each function.
5. Fit a new cut and hold knife and inspect the aluminium rollers for tack build-up.

Tools: Torque wrench, Spanners, Tyre gauge