Flexi coupling refurbishment

[Bunji]

Hi all,

New member here down in New Zealand. A few months ago I purchased a 72 Toledo 1300, which has recently failed a WOF (NZ equivalent of MOT I believe) due to play in the steering at the firewall and flexi coupling.

After a lot of reading on the forum, and consultation with my mechanic (very on to it vintage chap) I have come to the decision to:

- Replace the bulkhead bush
- Replace the upper steering joint and intermediate shaft with one from Rimmers (which they assure me is forged steel)
- Attempt to refurbish the flexi coupling with new poly bushes from Superpro/Superflex
- As a backup/alternative, buy a forged T2000 upper joint from Chris Witor, to use in place of the flexi coupling

My main question is, when refurbishing the original flexi coupling, how likely is it the original bolts can be re-used?

It appears the Triumph part number is 10897. It seems these are not ready available to source?

Appreciate any helpful advice. Cheers.

[Richard the old one]

I have found that the original bolts can't be used and that new ones are not available.

[xvivalve]

If you are lucky, the original equipment/early items have wire locked bolts and I have managed to rebush such a joint using the original bolts. Unfortunately, most joints are later/aftermarket items and rather than wire locked, the ends of the bolts are peened over; undoing these bolts destroys the peening and they are not long enough to be peened over again.

It wouldn't be beyond the wit of an experienced man with a lathe to make new ones though...

[Richard the old one]

I did produce an article which was published in edition 203 of Dolly Mixture June -July 2021 titled some notes on the lower steering coupling part. What follows is a part of that article which may help you.

Now we move onto another interesting point and the main reason for writing this article. When I spoke to Chris Wittor to purchase the Superflex refurbishment kit he asked me which design of coupling I was proposing to refurbish as there were two different build standards for the couplings that basically look the same. He advised me that the easiest way to spot the difference before the item is stripped is to measure the thickness of the central disc. The slightly thicker disc is ¼ inch against the thinner which is only 3/16 thick. See Photo Lower steering coupling bits. The picture also shows that the two disc are drilled differently and take the different shaped bushes. Please also note that the securing bolts shown in the same picture have a ¼ inch BSF thread and then a 5/16th section up to the bolt head. It should also be noted that the hole in the centre of both designs of bush is 5/16ths.


The SuperFlex repair kit, pack part number SF374-1179TH which was designed for the thicker disc design has top hat shaped bushes as shown on the right hand side of the photograph. Chris did tell me that some owners do use this kit with the thinner disc.
The SuperPro repair kit, pack part number SPF1179K (or sold by Moss-Europe under part number 108977SPK) has conical shaped bushes
Back to the securing bolts I believe that some owners, when they have been rebuilding the coupling have been using ¼ inch BSF bolts or screws. I did not wish to do this because there would be some play between the bush and the bolt from the start. So being in lock down I had time to investigate what options there were for obtaining some manufactured to the original design. The outcome was that I obtained some 5/16th BSF bolts and filed them down so that I could run a ¼ BSF die down them. Basically I removed the 5/16TH BSF tread and reduced the shoulder length to suit. It would have been a simple task with a lathe to take say a 2 inch long 5/16th BSF bolt, hold part of the screw thread in the chuck, and then turn it down as required before parting it off to the required length. It was certainly a bit more difficult doing it by hand. See photograph of bolt before and after modification.

I did not drill the bolts so that they could be wire locked until I had fitted them in the assembly and I did manage to snap one 1 mm drill in the process of drilling the holes.
The original bolts that I obtained from Mick Dolphin did have screw driver slots cut into their heads which did make assembly somewhat easier as there is a need to tighten them a bit at a time.

The following photo shows the repaired item with one side wire locked.

[cliftyhanger]

There are many (repro??) lower joints that are not peened over or wire locked. I refurbed one with poly bushes a few months ago. I used some high strength thread lock, plus a single centre punch to the joint between bolt and thread.
I hve wondered if another solution to no available shouldered bolts is to use steel bushes on 1/4" cap head bolts?

[triumphdolomiteuk]

I did produce an article which was published in edition 203 of Dolly Mixture June -July 2021 titled some notes on the lower steering coupling part. What follows is a part of that article which may help you.

Issue 203 is available to download from the Dolly Mixture Archive in the members-only forum.

[Bunji]

OK so I will have to measure the centre disk. Looks like the bolts are the original wire locked ones.

[Richard the old one]

I hope that having been told and shown just a bit of the Dolly Mixture article this will prompt you to join the Triumph Dolomite Club.

[cliftyhanger]

OK so I will have to measure the centre disk. Looks like the bolts are the original wire locked ones.

Yes, that will be simple to refurb with a set of new bushes.