David Hawkins and his DH22

Have got my DH22 back together and into the shed late last year. It still needs work on the engine to free it up properly before I do a full restoration but at least after repairing the clutch and transmission brake I can now move it around.

I split the tractor to free up the transmission brake because when I tried to shift it the back wheels would skid. What I found was that the bell housing, at some stage while sitting out in the open, had half filled up with water which had rusted the brake disc to the two friction plates. I dismantled the brake after much prying and hammering and found the disc to be in good condition, once cleaned up. One friction plate was beyond it so I made a new one, and the other one polished up OK. One of the springs was rusted away and the head on one of the mounting bolts was so deformed that the only way I could remove it was to weld a piece of flat steel to it and wind it out with a shifter. I found three springs the same length and about the same other dimensions as the original ones, and reassembled the brake and it worked quite well.

To repair the clutch, I cut the two fork arms off the cross shaft and used them as templates, (plus a bit) to fabricate new ones, which were welded back to the shaft. I got a new thrust bearing from BSC in Wagga and assembled the bearing and sleeve and fitted it on the guide over the front gearbox shaft. With an angle grinder I fashioned the end of the fork arms, through trial and error, to suit the sliding sleeve.

The clutch was also very rusty looking so out it came, in the process breaking off 6 of the mounting bolts which were rusted almost halfway through. The clutch plate was salvageable and I skimmed the flywheel face and pressure plate in the lathe, at work, to true up the faces and get rid of some of the rust pitting. I drilled and tapped out the broken bolts (bit of a bugger, all the threads are BSF or Whitworth) and got new ones from BSF bolts in Melbourne, who advertise in the Restored Cars magazine. I replaced 6 of the pressure plate springs with old truck valve springs fitting them to every second bolt around the pressure plate. So I had an old spring next to a new one all the way around. The valve springs were very close to the original spring dimensions but fractionally shorter, so I packed each of them up with a flat washer giving them an acceptable height.

I slipped the tractor back together and the clutch and brake both work well.
I solved the rear tyre problem by fitting a pair 10.00x20 rag truck tyres that one of the tyre dealers gave me. They stand about the same height as the original 10.5x20 tyres, and they look the part.