How to Perform a Clutch Update on the Agrowdrill AD230

Why have we made this change?

The original AD230 clutch offered a reliable method of ensuring the seed drill’s drive engaged and disengaged quickly and effectively. However, it required precise calibration. Some users have found it difficult to ensure that the clutch was calibrated effectively and experienced premature wear on their clutches as a result.

This update modifies the clutch design, making calibration easier, increasing error tolerance, and decreasing potential wear.

What has changed?

Clutch slide

The modified clutch slide incorporates a set of springs on the hub-facing side. These springs create tension against the drive sprocket to ensure neater engagement against the dog clutch. It also has a wider channel to accommodate the clutch fork, offering greater tolerance during calibration.

Clutch drive

The new clutch drive is zinc-plated instead of painted. This reduces the friction where the roll pins engage with the drive is lower, resulting in less wear.

Clutch fork wear plate

The new design has changed from steel to a nylon wear plate. This material minimises wear and is easier to replace if the fork should rub against the interior of the channel in the clutch slide.

Dog clutch offset washer

This washer offsets the position of the clutch lever arm assembly, making adjustments to the position of the clutch fork easier.

Tools and Parts Required

AD230 Clutch Kit (640-2078)

Tools Required

• AD230 Parts Manual (version 1910 or higher)

• AD230 clutch update video

• Spanner roll and socket set 10-24mm 

• Roll pin punch set

• Mallet

• Vice grips

• Sandpaper

• Thread locker

• Grease gun

• Brake cleaner spray

Process

1. Preparation 

1. Raise the AD230 into a disengaged position to remove pressure on the drive and clutch assemblies. 

2. Check appropriate safety measures.  Lock the hydraulic pressure off, take the keys out of the tractor apply park brake and insert the safety chocks in the wheel hydraulics. 

3. Remove the clutch bay guard by undoing the two hinge bolts on either side. 

4. Remove the Farmscan pickup sensor (640-4171 & 114-3023) from the side of the clutch bay. 

2. Disassemble the clutch assembly

1. Loosen the chain tensioner (640-4240) and unhook the tension spring (640-4203) from the clutch lever assembly.  

2. Remove the bolt that links the clutch lever assembly to the clutch arm. Lower clutch arm (640-4140) from the clutch lever assembly. 

3. Remove the chain (640-5008) linking the clutch assembly to the drive wheel to gain access to the roll pins on the sprocket. You may need to remove the chain link to do so. 

4. Remove the clutch lever pivot (640-3087). 

5. Knock out the roll pins (112-4036) from the clutch drive shaft. 

6.  Knock out the roll pin (140-4121) mounting the clutch slide to the clutch shaft. 

7. Remove the five nuts mounting the uni-hub (161-0120) to the side of the clutch bay. 

8. Gently slide the clutch shaft and hub towards the centre of the seeder to allow enough clearance to remove the sprocket (640-4076) and clutch drive (640-4075) from the clutch shaft.

9. Remove the nut on the hub side of the clutch lever assembly. This will allow you to remove the clutch lever shaft (640-4081), along with the remaining parts of the lever assembly.

10. Remove the clutch slide (640-4077). 

3. Assemble the new clutch assembly

1. Unscrew the grub screws securing the drive sprocket (640-4076) to the old clutch drive (640-4075). Wipe down the grub screws, apply a thin layer of thread locker, then secure the sprocket to the new zinc-plated clutch drive. 

2. Wipe excess dirt from the clutch and clutch lever shafts and the interior of the clutch assembly bay. Brake cleaner spray will make this easier. 

3. Apply a generous amount of grease to the clutch and clutch lever shafts. 

4. Fit the new nylon fork (640-4324) to the new clutch lever pull (640-3086). Be sure to note which side of the clutch lever pull the wear plate is mounted to (see parts manual p41) .on the left of the clutch slide. 

5. Swap the Farmscan magnet (640-4234) to the new clutch slide (640-4077) and refit it to the clutch shaft. You may need to adjust the position and angle of the hub and clutch shaft to provide enough clearance to fit the clutch slide. 

6. Fit the assembled nylon fork and clutch lever pull to the clutch lever shaft and replace the assembly in the clutch bay, ensuring the fork is resting in the channel in the clutch slide. 

7. Fit the new springs (132-2006) in the clutch slide. 

8. Put the new clutch drive and sprocket back on the clutch shaft. You may need to sand back the igus bushes prior to fitting if they have been replaced.

9. Tighten the five nuts around the uni-hub and tighten the nut securing the clutch slide shaft on the hub side of the clutch bay. 

10. Replace the roll pin (140-4121) that secures the clutch slide on the clutch shaft. Ensure the roll pin is flush with the clutch slide. 

11. Replace the clutch lever pivot (140-3087) and spacer washer (135-3036) onto the clutch lever shaft, followed by the nut. 

12. Reattach the clutch arm to the clutch lever pivot.

13. Refit the clutch lever spring. 

14. Hammer in the new roll pins (112-4036) on the end of the clutch shaft.

15. Refit the chain on the drive sprocket, the chain tensioner, and the Farmscan pickup sensor. 

16. Use a grease gun to apply lubrication to the grease nipples on the clutch slide, the clutch lever pull, and the clutch fork groove on the clutch slide. 

4. Calibration & testing

1. Ensure the drill is on a flat surface where both the wheels and tynes can touch the ground at the same time. 

2. The clutch fork should be positioned centrally within the channel of the clutch slide. It requires a minimum of 1mm between the fork and either outer edge of the channel. 

3. Adjust the position of the fork within the clutch slide channel by tightening or loosening the M16 nyloc nut (134-4022) on the end of the clutch fork shaft. 

4. Raise the drill off the tynes to ensure the mechanism stays in place when the drill is raised and lowered, and correct disengagement is applied when the drill is fully raised to ensure that the clutch is disengaged whilst in transport mode. 

5. Test both clutch engagement and positioning of the clutch fork several times to ensure the clutch fork is correctly adjusted. This can be done by repeatedly engaging and disengaging the clutch as the seed drill is towed through a paddock.