Welger AP 630 / AP 730 service schedule

1. Disengage the PTO, stop the tractor engine, take the key out and apply the brakes.
2. New or repaired baler: after the first 20 working hours, tighten all bolts and nuts. Do not move the adjusting screws.
3. Check the wheel nuts are at their torque. The manual lists 270, 160 and 120 Nm for the different wheels, but the scan does not show which is which: check your handbook.
4. Check tyre pressures: 10.0/75-15.3 and 11.5/80-15.3 at 2.3 bar; 7.00-12 and 8.00-12 at 2.0 bar.

Tools: Torque wrench, Socket set, Tyre pressure gauge

1. Lower the thrower, disengage the PTO, stop the tractor engine and take the key out. Release the hydraulic pressure as the manual describes.
2. Drain the thrower oil into a tray.
3. Change the filter if your thrower has one.
4. Refill with HL 46 to the level mark and check for leaks.
5. Check the thrower belt tension while you are there, as the manual shows.

Tools: Drain tray, Spanners, Funnel, Gloves

1. Park on level ground, disengage the PTO, stop the tractor engine, take the key out and apply the brakes. Wait for the flywheel to stop completely.
2. Take out the oil filler plug.
3. Take out the drain plug and drain the oil into a tray. Take out the level plug on the side of the housing.
4. Clean the drain plug, refit it and tighten it.
5. Fill with SAE 90 hypoid oil until it starts to run out of the level hole. That is about 3.5 L in an AP 630 and 4.0 L in an AP 730.
6. Refit and tighten the level and filler plugs. Take the old oil to a proper disposal point.

Tools: Drain tray (5 L), Spanners for the filler, level and drain plugs, Funnel, Gloves, Rags

1. Disengage the PTO, stop the tractor engine, take the key out and apply the brakes. Wait for the flywheel to stop. Lock the knotter release with its safety bolt.
2. Wear gloves: the twine holder knife and needle points are sharp.
3. Clean the twine holder and knotter with a suitable cleaner.
4. Knotter spring: spring height D should be 23–28 mm. Adjust with the lock nut.
5. Twine holder spring: its height should match the gauge finger next to the spring (control measurement E). Correct it with the adjusting screw.
6. Twine flicker: slacken the lock nut, back the bolt off until the flat spring is free, then screw it in until it touches and give it 3.5 more turns with twine in the twine holder, or 4.0 turns with none. Tighten the lock nut.
7. Trip the knotter, turn the flywheel by hand in the normal direction until the twine flicker stops, and check gap G is 1–2 mm. Adjust the threaded rod if not.
8. After fitting a new twine guide plate, check gap H between the nose and the knotter is 1.5–2.5 mm. Correct it with shims.
9. The twine retaining spring should sit against the nose of the guide plate under slight tension. The spring is under load: keep fingers clear when you slacken it.
10. Twine brake: spring length K is 26 mm.
11. If you take the knotter out, push the pins out of the bevel gear, put a little multi-purpose grease on the twine holder and knotter shafts and wipe off the excess. Refit the pins so the twine holder knife and the knotter tongue roller both point at the face of the bevel pinion.

Tools: Spanners, Pin punch and hammer, Rule, Feeler gauges, Gloves, Rags and a cleaner for the twine holder

1. Disengage the PTO, stop the tractor engine, take the key out and apply the brakes. Wait for the flywheel to stop. Turn the flywheel by hand only.
2. Needle operating rod: length L is 504 mm hole centre to hole centre. Adjust by slackening the lock nut and turning the rod shaft.
3. Trip the knotter and turn the flywheel until the needles are at the top. Measurement A (flat spring to needle tip) should be 90–105 mm; if not, reset the needles in their holders.
4. Measurement B (needle tip to top of the cross rail) should be 138–143 mm. Adjust with the needle frame bolts as the manual shows.
5. Gap C between needle and flat spring must not be more than 1–2 mm. Straighten a needle that is out.
6. Straighten or replace bent needles. A bent needle frame must go back to its original shape or be replaced.
7. Check the needle brake. Replace the friction linings when worn and keep oil and grease off the brake.
8. Packer timing (after repairs): with the packer crank parallel to the top of the packer box, rod head measurement J should be AP 630: 170 mm (170–185 mm after releasing the jam); AP 730: 330 mm (330–350 mm).

Tools: Spanners, Rule or tape, Wooden block (to jam the drive), Gloves

1. Disengage the PTO, stop the tractor engine, take the key out and apply the brakes. Wait for the flywheel to stop.
2. Find out what jammed the needles and clear it first.
3. Needle bolt: take out the split pin and bolt, swing the operating rod down and pull it off the rod shaft. Remove the broken pieces of shear bolt.
4. Refit the operating rod and screw in a new genuine shear bolt 0901.98.10.00.
5. AP 630 main drive: check the shear bolt on the rear conical clutch is an M7 × 50 grade 8.8 and is tight, with its M7 nut and spring washer.
6. AP 730 has an auto-reset clutch instead of a main drive shear bolt.
7. After any jam, recheck the needle measurements before baling again.

Tools: Spanners, Pin punch, Pliers for split pins, Gloves

1. Take the PTO shaft off the tractor, stop the engine and take the key out.
2. Front plate clutch: clean rust off the flywheel friction face with emery paper.
3. AP 630 cone clutch: undo two diagonally opposite bolts of the eight and screw them back in 3–4 turns. Take the other six out.
4. Free the flywheel with a punch and hammer through the hole in the back of the flywheel guard, turning the flywheel between blows.
5. Jam the drive with a wooden block in front of the ram knife and turn the flywheel several times.
6. Refit the bolts and tighten all eight evenly.
7. The clutch torque is set at the factory (AP 630: 600–800 Nm) and normally needs no adjustment. If linings or friction blocks are badly worn, replace them. Never leave out any shims when rebuilding.

Tools: Spanners, Punch and hammer, Wooden block, Emery paper, Gloves

1. Disengage the PTO, stop the tractor engine, take the key out and apply the brakes.
2. Pick-up: set the working height so the tines run about 2 cm above the ground and never touch it. Replace broken or bent tines.
3. Twine: stand the rolls upright in the twine box with the start and end at the top. Tie the rolls in the top box together so you thread less often.
4. Thread the twine with the needles and tying mechanism in the home position (needles at their lowest) and the knotter release locked.
5. Grease all points with two strokes of multi-purpose grease, and shorten the intervals in heavy work.
6. Check the gearbox oil level at the level plug.
7. Run at 540 rpm PTO and no faster.

Tools: Grease gun, Spanners, Tape measure