Sheared shackle plates beware!!

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jollyroger
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Sheared shackle plates beware!!

Post by jollyroger »

Hi, Car due MOT soon and on pre inspection the 4 shackle plates on the rear springs had all sheared. They are lengthened ones that I bought from a supplier a few years ago.
Just a warning to anyone else who has these to check them. There was noting noticeable about the handling of the car to indicate there was anything wrong either.
Shackles.JPG
Shackles.JPG (1.9 MiB) Viewed 5094 times
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firedrake1942
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Re: Shackle plates beware!!

Post by firedrake1942 »

I think we need to know who the supplier is so that this can be more widely promulgated. Notwithstanding the dementor's usual policy of deleting anything that remotely criticises suppliers / traders, this is a real safety issue. They look less meaty than the shackles I recall on mine -I once failed an MOT because the previous owner had put them on back to front! and it appears that the bolt heads are all that have kept them in place.
les
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Re: Sheared shackle plates beware!!

Post by les »

What does the extra length do? I wonder if it allows more flexing.

firedrake1942
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Re: Sheared shackle plates beware!!

Post by firedrake1942 »

I think we need to know who the supplier is so that this can be more widely promulgated. Notwithstanding the dementor's usual policy of deleting anything that remotely criticises suppliers / traders, this is a real safety issue. They look less meaty than the shackles I recall on mine -I once failed an MOT because the previous owner had put them on back to front! and it appears that the bolt heads are all that have kept them in place.

The ones on Flaebay do not look as robust as my originals although I may be wrong.

https://www.ebay.co.uk/i/160962030379?c ... 931&crdt=0

https://www.ebay.co.uk/i/262710565804?c ... 931&crdt=0

There is also potential extra horizontal flex in the longer ones which may not be an issue in the shorter ones, contributing to the catastrophic failure in the pictures ,
LouiseM
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Re: Sheared shackle plates beware!!

Post by LouiseM »

firedrake1942 wrote:I think we need to know who the supplier is so that this can be more widely promulgated. Notwithstanding the dementor's usual policy of deleting anything that remotely criticises suppliers / traders, this is a real safety issue.
It isn't the 'dementors policy' as you put it, it's a club one. These are not standard shackle plates, they tend to be used with uprated suspension. It isn't clear how along ago they were purchased but first thing OP should do is contact the supplier. If the problem is down to the manufacture of the plates rather than other issues the supplier will be in a position to directly contact other customers who have purchased the same items. In the meantime I would suggest that anyone here who has the longer shackle plates fitted to their Minor checks them carefully, and can also contact the OP via pm to establish the name of the supplier.


Eric - 1971 Traveller
firedrake1942
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Re: Sheared shackle plates beware!!

Post by firedrake1942 »

sigh......
philthehill
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Re: Sheared shackle plates beware!!

Post by philthehill »

The longer shackle plates are usually fitted to jack up the rear end of the car so giving the car a nose down appearance.
That extra length does put additional forces on the shackle plate in addition to the extra forces placed on the rear chassis legs..
The distance between shackle pin hole centres on a standard shackle plate (Pt No: ACA5251 (MOSS) is 2 3/8".
Can you please measure the distance between centres of the plates that have failed and post on here as the shackle plates in the above photos do not look any longer than standard and you may be making a wrong call.
Saying that it still does not get away from the fact that the shackle plate fractured.
Were the shackle plate nuts tight and the shoulder of the pin hard up against the plate?
The shackle pin is not always a good fit into and against the shackle plate as the shoulder of the pin is not always square (it should be) and when the nut is considered to be tight the shoulder of the pin is not hard against the plate - over time the pin and the plate move against each other and stress fractures appear in the plate which can ultimately lead to failure of the plate.

Below is a picture of a standard shackle plate.

http://www.gsjones.co.uk/443-thickbox_d ... ates-2.jpg

RobThomas
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Re: Sheared shackle plates beware!!

Post by RobThomas »

Is there any chance of a clearer picture, JR? Also, a PM if poss with the name of the supplier? Thanks.

PS Did the spring washer go directly against the plate or was there a flat washer between them?
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Plin
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Re: Sheared shackle plates beware!!

Post by Plin »

:-? could have been nasty - well spotted. Hope your car passes it's MOT without further problems.
firedrake1942 wrote:sigh......
Yes it is a shame we are made aware of problems but cannot be stopped from purchasing the same iffy parts as we are not allowed to know who supplied them. But we have to abide by the rules to keep things running smoothly.

(By the way Firedrake thanks for making me search the dictionary quite often!)
firedrake1942
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Re: Sheared shackle plates beware!!

Post by firedrake1942 »

My point is that libel laws allow a 'Fair Comment' defence and provided that is adhered to, that there is factual comment and no malicious intent to damage either a company or personal reputation, there is no need to be quite so erinaceous. (Go on look it up - I had to!)
philthehill
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Re: Sheared shackle plates beware!!

Post by philthehill »

I just cannot believe the above comments in that the inference is that the parts are faulty and members should be made aware of the manufactures name - all without being aware of the full facts.
The parts in question may not be of faulty manufacture.
Even companies are innocent until proven guilty.
Questions need to be asked and answered before jumping to conclusions.
For a start - I have asked above what is the distance between hole centres to determine if the shackle plates are standard length or longer.
If they were longer why were they fitted?
Again were the shackle pin shoulders butted up against the shackle plates?
I have described above a likely scenario of what could have happened.
Whilst the OP may have fitted the parts properly - the parts in question have to be fitted properly and in line with the Minor Wksp manual.
When all the questions have been answered then a subjective answer as to why the failure of the shackle plates can be determined.
Phil

firedrake1942
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Re: Sheared shackle plates beware!!

Post by firedrake1942 »

Phil, your questions are valid but many are unlikely to be satisfactorily answered. Most of these parts, with different suppliers are likely to have a common manufacturer and IF there is a problem we need to know about it whether they are longer shackles or standard - I tend to agree they look standard sized.

Many of the originally produced parts cannot simply be lifted from scrap vehicles anymore and have been reproduced with significantly less quality materials than originally used. Where these are cosmetic there is no great problem. Where they are structural or load bearing then it is a problem. people ought to be able to vote with their feet if they wish. Suppliers and manufacturers need to know if products are found to be potentially defective as Louise has suggested.
les
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Re: Sheared shackle plates beware!!

Post by les »

I also like to know where faulty stuff comes from but these items may or may not have been caused by inferior quality, I don't think I would necessarily condemn a suppliers in this case. Although I don't know, the items look like they've seen some service.

RobThomas
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Re: Sheared shackle plates beware!!

Post by RobThomas »

Interesting that the failed ones have the hole centred at about the same height as the end of the 90 degree bends and thus is a prime candidate for crack propagation. The ones in the link Phil added above have the reinforcement 90 degree bend extending beyond the hole.
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jollyroger
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Re: Sheared shackle plates beware!!

Post by jollyroger »

The plates were purchased about 6 years ago and fitted with washers against the pin. They were purchased as one side of the rear spring was rubbing against the inner wing very slightly. They were removed 4 years ago and bushes replaced when the car was restored. I have contacted the supplier to alert him to this. They were longer shackles that were available for modified minors. I don't want to get into naming and shaming on here and I happy to pm anyone who wants details.
[img][/img]
les
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Re: Sheared shackle plates beware!!

Post by les »

You raise a good point, Rob.

firedrake1942
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Re: Sheared shackle plates beware!!

Post by firedrake1942 »

Jolly Roger in response to your pm

I don't know the suppliers you have named in your pm, but I suspect they will have sourced them from elsewhere and I would get in touch with them to find out where, as again I suspect whoever manufactures them will supply others. It may be as Phil says that fitting (Whoever has done this) etc has had an effect but even with the originals I have never seen this level of degradation.

It could be that you will get 'we have never had that problem before' type answer but if we can identify the source and / or manufacturer, concerns can be passed on. Many garages , restorers may be fitting them in perfectly good faith and perfectly well, but need to be made aware of even one fatigue type failure as this. Phil's advice can be further disseminated and given in Minor Matters re tightness, washers and fitting as well as regular inspection if new shackles have been fitted.

The point regarding the centre holes being close to the end of the 90 degree bend is a good one as regards fatigue and cracking. Neither of the ones on eBay are like the failed ones and resemble Phil's.

Keep us updated!
philthehill
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Re: Sheared shackle plates beware!!

Post by philthehill »

The length of the edge/side reinforcing bend on an original genuine BMC shackle plate is 77mm.
What is the length of the edge side reinforcing bend on these modified/longer shackle plates?
The OE shackle plates fitted to my Minor which are of standard length do have the edge/side reinforcing bend extending beyond the shackle pin hole as per the one in the link I posted above.
What is the thickness of the metal used in these longer shackles?
I would still like to know the distance between shackle plate pin hole centres please.
Where the longer shackles fitted to both springs or to just one side of the car?
From what I can see in the top photo - one of the shackle pins (not the one in the photo) appears to have been turning in the shackle plate for some time.
Whether that ability to turn was caused by the wrong thickness of metal used for the shackle plate so that the nut bottomed out on the threads or the shackle pin shoulder not fully butting up against the shackle plate remains to be seen.

RobThomas
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Re: Sheared shackle plates beware!!

Post by RobThomas »

Just looked at some I have in a bag in the garage and they are not bent round the edges but are massively thick. If the cross-pins (?) are designed to have threads that are sufficient for thick plates then maybe, as Phil says, the threads have bottomed out before they clamped the thinner plates. Could the cross-pins actually be the pins meant to go through the eyebolt and into the torsion bar? They are the same dimensions (unless I'm mistaken...and I may be) but may have different thread lengths.
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firedrake1942
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Re: Sheared shackle plates beware!!

Post by firedrake1942 »

Went under my car yesterday and it has the originals on and they do seem much thicker than the failed ones or the ones on eBay. The centre of the holes are also way lower than the failed ones.
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