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Old 18th March 2021, 09:41   #61
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I'm pretty sure fellow member norfie can answer any query about tyre protectors and how well they work. He was part of the development team that designed and field tested them at MGR. For example see this thread esp Post 4: https://www.the75andztclub.co.uk/for...ad.php?t=99965


For what they cost (about a fiver originally) fitting tyre protectors is a no brainer IMO.
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Old 18th March 2021, 10:32   #62
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I fitted a pair of these tyre protectors today. The screws that hold them in place are quite weedy IMO. I presume the protectors are just meant to catch a loose, broken off bit of spring, not support the corner of the car on the broken, shortened spring? I was also surprised they were not lhs/rhs handed.
Once the spring breaks (given the nature of the material I don't think they could simply distort but not fracture...) then the potential energy from the compressive forces you'd expect to be constantly present during normal use will have, by and large, been lost. Then you have a very complicated series of possible conflict scenarios for bits of spring dynamically entwining with each other; regardless, the energy/power of the whole spring immediately disappears/is vastly reduced to be replaced by a significantly shortened spring and more of a 'spongy deadweight' (hopefully) keeping the collapsed spring enmeshed but captured by the protector with the sharp bits safe/clear of tyre rubber.
I've warned members that there are 'genuine' replacement dampers out there that have apparently been re-tooled and will NOT accept the MGR protector kit; it's a subtle design change and if you have replacement dampers already fitted you will soon know if you attempt retrofit protectors.
The safety aspects that were raised when this problem surfaced in 2003(?) and the fact that the then OEM took recall action suggests real liability issues existed.
I'm not sure if MGR started fitting protector kits on the production line but under normal circumstances the quick fix recall/field modification would have been designed out ie the strut lower spring plate would probably have incorporated a retaining feature (an upturned flange...?) by the manufacturer (Delphi I think but there could have been other suppliers). It's unfortunate that in 2005 MGR went bust so I guess it got 'overlooked' unless someone on here (for sure) knows differently.
Early days SIAC should have continued to either fit kits or introduced a modified damper - it's a dangerous design fault! Anyone out there know more to the contrary? Whatever, new (China?) factory dampers (using modified tooling..?) appear to still have the same design 'fault' after 15 years but as yet no retro kit (not even a warning) available. In this case are they selling dangerous products? Not knowing is one thing, knowing but doing nothing about it is entirely different.
All I'm suggesting is buyer beware
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Old 18th March 2021, 13:41   #63
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...
I'm not sure if MGR started fitting protector kits on the production line but under normal circumstances the quick fix recall/field modification would have been designed out ie the strut lower spring plate would probably have incorporated a retaining feature (an upturned flange...?) by the manufacturer (Delphi I think but there could have been other suppliers). It's unfortunate that in 2005 MGR went bust so I guess it got 'overlooked' unless someone on here (for sure) knows differently...
I picked up my protectors at Wilcox MG. I had a chat about them and they said they fit protectors if not already fitted when doing suspension work on 75s, and they have seen later models without them.

The technical note I saw was just covering 75 saloons of a limited band of serial numbers, almost as if the defect was sentenced as as a spring quality fault for a batch, rather than a design fault. I don’t know if there were other tech notes for other models/ ser. nos.
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Old 18th March 2021, 17:02   #64
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Originally Posted by T-Cut View Post
... fellow member norfie ... was part of the development team that designed and field tested them at MGR. For example see this thread esp Post 4: https://www.the75andztclub.co.uk/for...ad.php?t=99965
Thanks for this T-Cut. In the link norfie says that "we changed the spring manufacturer in the end to cure this problem". This suggests that the protectors were not as successful as they'd hoped.

Here's a photograph from the link posted by pab:



As you can see, tyre protectors were fitted but they didn't contain the fractured end. That's exactly what happened on my car without tyre protectors.

It would appear that the only reliable solution is to change the springs for the current genuine parts which (for my car) are made by Suplex.

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Old 18th March 2021, 17:09   #65
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I picked up my protectors at Wilcox MG. I had a chat about them and they said they fit protectors if not already fitted when doing suspension work on 75s, and they have seen later models without them.

The technical note I saw was just covering 75 saloons of a limited band of serial numbers, almost as if the defect was sentenced as as a spring quality fault for a batch, rather than a design fault. I don’t know if there were other tech notes for other models/ ser. nos.
Noted but springs still go twang, our cars aren't the only one's. Many on here report it happening at very low speed and during cold weather, some don't even know it's broken and come across it by accident or at MOT time. The nature of spring steel means it can develop early fatigue cracks if it's not of the best quality (one manufacturing treatment shortcut is to not shot peen the finished spring prior to any coating, this encourages early onset macro surface fissures). All the breaks I've seen are classic 45deg shear fail fractures that appear to originate from a corrosion site - in short perhaps it is/was a specific MGR supplier QC issue.
Regardless, a spring failure combined with a tyre breach at speed is bad news all round and with the historical background I described in an earlier post it's a dodgy legal position in the event of death(s)
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Old 18th March 2021, 18:21   #66
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Noted but springs still go twang, our cars aren't the only one's. Many on here report it happening at very low speed and during cold weather, some don't even know it's broken and come across it by accident or at MOT time. The nature of spring steel means it can develop early fatigue cracks if it's not of the best quality (one manufacturing treatment shortcut is to not shot peen the finished spring prior to any coating, this encourages early onset macro surface fissures). All the breaks I've seen are classic 45deg shear fail fractures that appear to originate from a corrosion site - in short perhaps it is/was a specific MGR supplier QC issue.
Regardless, a spring failure combined with a tyre breach at speed is bad news all round and with the historical background I described in an earlier post it's a dodgy legal position in the event of death(s)
Agreed. Protectors now fitted and I’ll keep an eye on the springs, but am aware that the onset of critical damage leading to failure may not be obvious.
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Old 18th March 2021, 19:39   #67
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Always better fitted than not is my opinion, at least it gives you a chance of not having to fork out for a new tyre, and may save you going into a ditch or off the road, whereas without them fitted you don't have that chance.
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