Trunnion troubles

[davidj]

Hi,

My car has just failed the MOT due to worn trunnion on the passenger side. Normally I would simply purchase the standard triumph replacement, but is there an improved 21st alternative or even an superior manufacture for the standard part? Please note I am not looking at replacing the suspension with a spyder style upgrade, just the trunnion!

Thanks in advance for any comments!

Cheers,

David

[gerrym]

David, not trying to be flippant but you should hope to get something as good as the original Stanpart item. Speak to the Triumph dealers, most of what is being flogged are Chinese or Indian copies. Otherwise check with a Triumph specialist scrappie, GT6 for Plus 2, Brian Buckland details various Elan fitments.

Also, just a thought, if the trunnion has just the failed the MOT, do you need just a new brass lower trunnion swivel (female thread) or a new upright (cast male thread)?. Where's the wear?

Regards

Gerry

[oldelanman]

Canley Classics do a conversion which replaces the trunnion with a ball joint - anyone fitted that to an Elan ?

[elan_fan]

T D Fitchett in Telford supply the suppliers, the one from them has Stanpart cast onto it and is machined correctly to denote left or right fittment. Check you upright though for wear as per the book as it is the upright that will fail at the top of the tread not the trunnion. Any probs getting one PM me and i'll pick a couple up for you

regards
Mark

[ppnelan]

Canley Classics do a conversion which replaces the trunnion with a ball joint - anyone fitted that to an Elan ?

Do they fit a seal?

Matthew

[bcmc33]

Canley Classics do a conversion which replaces the trunnion with a ball joint - anyone fitted that to an Elan ?

Do they fit a seal?

Matthew

I asked that question - and they thought it was a stupid one.

Why would you want a seal? - now there's a stupid question.

[davidj]

I thought the conversion was quite clever until Matthew asked to obvious question. Why would you want a seal? Grit in the ball joint polishes the surfaces and beds everything in, a bit like lapping paste, but cheaper.

How do you test if it is the brass trunnion or upright which has failed? I was assuming it was the trunnion but it could be the upright. I am in the process of pulling the suspension apart, but at the MOT station with a crowbar (!) under the wheel, the play was vertical.

Cheers,

David

[bcmc33]

The Buckland book, page 286, shows what the upright should and should not look like.

My car failed the MOT three years ago due to excessive play in the trunnions. I took the car home, pumped them full of semi-fluid grease, cleaned the outer surfaces with wire wool and took it back next day to be told they were perfect.
I now give them a couple of pumps with the grease gun the day before the MOT is due.

[davidj]

Hello again. Just pulled the trunnion off and the thread on the upright is totally shot. Fitchett do stock the uprights as well but will only quote for Triumph parts. Just as a sanity check for me before I blow ?130 on two new uprights, they are GT6 parts for the +2 are they not? I am sure they are but it is always useful to have conformation!

Cheers,

David

[davidj]

I wonder if the Canley Classics conversion would work? At ?239 it actually is not bad value if it includes the top and bottom joints and you have to replace the upright anyway which will cost ?140. I actually spoke to a guy today with a Caterham who said there is a lot of discussion about seals on the bottom ball joint, but after 30K miles he has never had any problems.

I must admit I am tempted.......

David

[gerrym]

David, everything I have ever read tells me that GT6 parts fit all variants of the Plus 2. Do you have a copy of Robinshaw et al?

Regards

Gerry

[handi_andi]

Personally I would try the "spitfire graveyard", yes that's their company name, (http://www.spitfireg1.f9.co.uk/frame.htm) as when I had a trunnion shear off on a spitfire I got a complete upright from them and then brought a new brass female to make sure. They also have GT6s in their yard so you should be able to get one fairly cheap from them. Seem to remember I got a compelte corner of a spitfire in a box, so had some spare suspension arms etc to boot.

Cheers

Andy

PS If you keep getting worn wheel bearings chainge the trunnion before it breaks is what I learnt from that incident

[paddy]

To answer the question about which Triumph, then I think the answer is yes, any GT6 or any Vitesse, if it's only the upright you want. If you're going for the assembly including caliper mounting plate then it's GT6 or Vitesse MK II.

On a separate point, I'm a bit puzzled by the Canley design being described as a "ball joint". The trunnion normally only turns to allow the upright to steer and the movement for bump/droop happens at the joint between the trunnion and wishbone. If this was a ball joint instead, then wouldn't the lower part of the joint need to be fixed rigidly to the wishbone? And wouldn't that change the geometry? If instead the joint on the Canley item just allows rotation in the same way as the trunnion then I would believe that the absence of a seal might not be so much of a problem.

Paddy

[handi_andi]

It actually appears to be described in their list of parts as a Rose joint, which makes things rather interesting. http://everything2.com/title/rose+joint certainly paints a gloomy picture of rose joints and how quickly they can wear out due to grit intake even with booties. The reverse side of the coin though is that it will depend what Canley Classics have manufactured the joint from and whether they have hardened the contact surfaces in any way. As theoretically it would be possible to make the surfaces that are in contact harder than common grit so that the grit gets it. Even they were smarter still then they would make the replaceable carrier slightly softer than the vertical link so that it preferentially wore.

Just had a quick look on line and similar questions are coming up in Spitfire and GT6 forums about the metal on metal contact. I think if Canley want to sell these to us weary buyers then they should provide a better explanation about how the bottom joint works personally.

Cheers

Andy

[davidj]

I think I am changing my mind again about the conversion. I think for it to work correctly it would have to be bolted solid onto the end of the wishbones, and from the design it looks to sit on top of the wishbones. This would change the steering geometry and I would be concerned about the single bolt fixture twisting.

D