Plus 2 - GT6 Steering Uprights New Quality?

[gerrym]

Spoke to a UK supplier of GT6 / Vitesse Steering Uprights. He assured me that the new items supplied by him are forgings, machined in the UK and "good quality".

If I'm running larger, grippier tyres than originally specified on the Elan Plus 2, this increases the loads on the trunnion thread. Does anyone have feedback on failures of new steering uprights, or generally on the quality of the items on offer. Is it related to tyre size, track use? or just old age and possible neglect?

For the original Vitesse or GT6 application, would the front axle weights of these cars with their straight 6 engines have been higher than the Plus 2? Did the Eclat use the same components? (bigger, heavier car, larger tyres etc etc).

Regards

Gerry

[Lotus fan]

I've just been through the same dilema myself !
I've bought mine from Canley Classics

http://www.canleyclassics.com/searchfor ... /VIT%20R/H

It certainly is of better quality than others I have seen.

Also picked up some of these too:-
Vitesse, GT6 stainless dust shields.

http://www.canleyclassics.com/?xhtml=xh ... roduct.xsl

No link to the above company etc.
Just a happy customer

Ian.

[gerrym]

Thanks for the reply Ian. I've always found Canley to be a reliable supplier and they are at least trying to offer innovative products. I think originally they only had the ss dust shields for the Heralds but I see they now from your link that they have a product for the GT6/Vitesse as well.

When you say quality of the upright appears better than some you have seen, is this based on surface finish from the machining?

Regards

Gerry

[Lotus fan]

The machining is rather good, not aircraft quality obviously.
What I meant was that some vertical links I have seen have pretty bad pitting around the hole where the steering arm goes and therefore might be a weak point
There's no pitting anywhere on the Canley vertical link.

I picked up a load of bits from Paul Matty's on Saturday and a vertical link was going to be one of them bits, but they said that they can't get hold of any 'till the end of April !!!
That was the reason I bought from Canley.

Ian.

[oldelanman]

Canley Classics also do a trunnionless conversion kit which has a ball joint at the bottom end of the upright, developed originally for the Caterham I believe.

http://www.canleyclassics.com/?xhtml=xhtml/product/catkit1.html&xsl=product.xsl

Again no connection with Canley - just interested in their products.This was discussed on here previously - do a search on trunnions you should pick it up.

You could also talk to Spyder and see what uprights they use on their Zetec Plus 2 conversions.
Regards,

[gerrym]

Not a lot of feedback on this one.

I'm taking silence to mean that there are very few failures with the GT6 uprights in Elan Plus 2 service, even with wider tyres, or that new uprights supplied by the quality Triumph specialists are at least adequate in quality (and don't fail rapidly in service).
By the way, there are lots of pictures on the net of broken down Triumphs with a broken upright (trunnion thread) but I've never seen one posted of a Lotus Elan. Are we lucky, perform an incredible amount of maintenance&inspection, too proud....??

As usual, this assumes adequate lubrication (but that is another story).

Regards all

[GrUmPyBoDgEr]

Not a lot of feedback on this one.

I'm taking silence to mean that there are very few failures with the GT6 uprights in Elan Plus 2 service, even with wider tyres, or that new uprights supplied by the quality Triumph specialists are at least adequate in quality (and don't fail rapidly in service).
By the way, there are lots of pictures on the net of broken down Triumphs with a broken upright (trunnion thread) but I've never seen one posted of a Lotus Elan. Are we lucky, perform an incredible amount of maintenance&inspection, too proud....??

As usual, this assumes adequate lubrication (but that is another story).

Regards all

It did actually happen to a Mate of mine in an S4, fortunately he was in a Company Car Park & going relatively slow (for him).
He did manage to hit a Concrete Bollard when the front Wheel gave up & the damage was bad.
Those uprights are good if looked after, just look at how many different Race cars used them in those days; much higher cornering forces & fatter Tyres.

Cheers
John

[gerrym]

John, thanks for your sensible reply. A little like my reasoning that the uprights were also used on the heavier, larger tyred Eclat/Elite.
As I'm not privy to how good or bad was the maintenance during the 30 years prior to my custodianship, I think I'm going to strip the front suspension (again) and a have a look with dye penetrant. I'm guessing that this will be sensitive enough without needing to go to UV type dye-pen. Then again, this might not work due to ingrained oil/gease absorbed into any cracks. Will need pretty good degreasing. (Many years ago, I had access to a fully contained hot "trich" vapour degreasing bath).
To calibrate what is a serious crack, it would be useful to examine a failed trunnion thread. Does anyone have one of these kicking around their garage?
Again, if anyone has been down this road already, please stop me re-inventing the wheel.

Regards

Gerry

[GrUmPyBoDgEr]

"(Many years ago, I had access to a fully contained hot "trich" vapour degreasing bath).
To calibrate what is serious crack, it would be useful to examine a failed trunnion thread. Does anyone have one of these kicking around their garage?"

My ol' man used to borrow Bottles of the stuff from Work, we used it cold at home, but I remember the "hot Tanks" in the Factory & the selection of Steel Hooks & Baskets, for the use of.
Fantastic stuff.
Health & Safety has ruined our lives

John

[ecamiel]

Years ago when I was racing a 7 (same uprights as baby Elan) I magnafluxed 14 NEW stub axels.
13 of them failed! Presumably modern manufacturing techniques are better.
Elans usually raced with GT 6 uprights and their larger stub axels.
Modern street tires probably have more grip, and so more load, then race tires of the 60s.
These uprights and axels should be inspected, magnafluxed, as part of any rebuild.
I can tell you from personal experience that the handling stinks on 3 wheels.

Eric
64 Elan S1 Hart

[mikealdren]

Is there any evidence for upright failing on the +2? My car had totally knackered trunnions when I got it, looked like they had never been lubricated, they were rusty and there wasn't much thread left but they hadn't cracked or failed.

Mike

[gerrym]

Mike, good question. Actually I'm not sure that the critical thread root diameter is any different between the Herald and GT6 uprights, (same brass trunnion part numbers anyone?) so we might as well extend the discussion to all Elans.

Whether the upright with a thread defect will fail or remain latent depends on the relative time (or cycles) where damage is just accumulating via crack growth versus final failure across the remaining cross-section. Examination of a recently failed thread section would give some indication as to that. I'm not surprised that we have a report of NDT failing the vast majority of a sample of axle machinings examined. Surface finishing will be responsible for some of these, either because cracks are directly from poor machining or because cracks have propagated from machining defects. Obviously if these are new and havn't seen any service, then the cracks are all down to poor manufacturing (possibly forging but probably machining defects)

So to answer your question, Plus 2s may be on the road with cracks that are growing from normal road stresses. They will eventually fail due to crack growth and then a final shear failure (low speed manoeuvre with very high lateral load). So at least we can take some comfort that probably the failure mode will be relatively "safe". Increasing tyre section and/or stickiness is probably one way of accelerating a failure, but more alarming perhaps, will raise the threshold of final failure from relatively benign slow speed to one that could happen at normal cornering forces . The corrosion aspect due to poor lubrication is just another way of introducing a defect (as opposed to maching defect)

To answer Eric, "presumably modern manufacturing techniques are better". I'm not sure about that. The pressure on classic parts manufacturers to produce cheap parts (presumably while keeping high margins for themselves, distributors and retailers) probably means that if anything, quality is worse than when these components were being produced new for current models.
So if I detect any cracks in my existing uprights, I'll certainly be checking any new replacements I buy as well.

Regards all

Mike, re-reading your posting with reports of worn out steel upright threads and brass trunnions, arguably that's a safer state of affairs because at least the MOT will pick up the relative movement/wear and cause a repair to be affected. Did you get the uprights crack tested in any case?

[gerrym]

I found a UKnsupplier for single cans of Ardrox 9VF2 dye pen, plus matching developer and cleaner ordered. The 9VF2 is dual visible light / UV fluorescent so should be very convenient to use. Developer will be two weeks delivery, so will report back on the state of my inherited unknown maintenance uprights.

Regards all

[Baggy2]

I had one snap at the top of the bottom trunion thread also fortunately in a car park. There had been no sign of problems prior to the failure.

[gerrym]

Baggy, thanks for posting your note regarding the failure. Hopefully it can help others make informed decisions as to maintenance and inspection. I'm going to assume that the failure was not of a recently replaced upright, at least an upright that you had replaced in your recent ownership. Let me know if this is not the case. Would you say that the trunnions were lubricated on a regular basis?. Were standard size tyres fitted? Do you still have the failed parts?

Finally, you say there were no previous symptoms, did you have anything particular in mind. General wear of the upright thread and then the bronze (brass?) trunnion might not be related at all to failure across the thread.

Regards

Gerry