Author Topic: Dragonfly clutch thrust bearing  (Read 935 times)

0 Members and 1 Guest are viewing this topic.

Offline triton999

  • Member
  • *
  • Join Date: Jun 2012
  • Posts: 12
  • Location: Bexley, Kent, UK
Dragonfly clutch thrust bearing
« on: 06 Aug 2021 at 10:07 »
I have rebuilt the top ends (?) of my 'Fly over the past few years after finding that the previous owner replaced the gudgeon pins without circlips. You can guess what happened! I then replaced the poorly welded-up rocker (!) but I'm afraid that the beast was left for a few years as a result of other things to do. Recently a friend converted it to negative earth 12v and rewired it for me to the extent that it is now ready to go. It started first kick and ran beautifully except for the screeching noise coming from the back of the engine as soon as the clutch lever was touched. It seems to me (novice) that the thrust bearing has dried out and a good greasing has not helped at all. Will I have to replace the thrust ring and ball bearings to cure this or does someone have a magical fix for me?  Grateful for any tips.

Offline eddie

  • Master Member
  • ****
  • Join Date: Mar 2006
  • Posts: 1861
  • Location: Hampshire, UK
Re: Dragonfly clutch thrust bearing
« Reply #1 on: 06 Aug 2021 at 18:21 »
Unfortunately, this is quite a common problem with postwar Douglases. The ideal repair would be to replace both the thrust ring and the clutch cam (as these both incorporate the bearing tracks) but they are becoming scarce. When you get your clutch release out, if it's not too bad, you may find that it can be reclaimed by having the tracks reground to suit 1/4" balls (7/32" was standard). When reassembled, adjust the cable so that there is some free play on the operating arm - if the thrust bearing is under constant load, it will soon start screaming at you again.

   Regards,
                 Eddie.

Offline eddie

  • Master Member
  • ****
  • Join Date: Mar 2006
  • Posts: 1861
  • Location: Hampshire, UK
Re: Dragonfly clutch thrust bearing
« Reply #2 on: 07 Aug 2021 at 06:43 »
I have just seen there are 2 clutch thrusts (amongst other bits) listed on ebay.

   Eddie.

Offline triton999

  • Member
  • *
  • Join Date: Jun 2012
  • Posts: 12
  • Location: Bexley, Kent, UK
Re: Dragonfly clutch thrust bearing
« Reply #3 on: 07 Aug 2021 at 12:22 »
Many thanks Eddie.  Fortunately post-war spares have got a complete used thrust bearing in good condition and I have bought that.