Clutch advice - why it failed
Discussion
Need a little help guys - and excuse my poor clutch terminology that follows!
Trying to avoid my kid getting a financial caning IF he's in the right.
Story, in April a BMW specialst changed the clutch on his E36 M3, in less than 3k miles the clutch has failed catastrophically - the pressure plate drive face (not the friction plate) has broken into 4 pieces. I understand that an OE quality full clutch assembly had been fitted inc a "guide tube"
The broken pieces had some signs of blueing - not heavy, but obviously some heating of the drive surface occured.
At the time of failure (couldn't change gear) I'm assured the car wasn't being driven hard, I believe him - he's sensible, loves his car and treats it a reassuring degree of mechanical sympathy Up until the time the clutch failed everything worked normally; no slippage and easy gear changes.
When no gears could be selected (changing from 5th to 4th) the car was stopped and he had a look around. Nothing obvious and no smells. From standstill with engine running nothing could be selected. He managed to select 2nd gear with engine stopped, started engine with clutch depressed and some drive was evident. Released clutch and managed to drive some 12 miles home in second gear by which time there was a distinct smell of burning clutch (cause of blueing mentioned above?)
Car was rcovered to specialist who has again replaced clutch with another LuK unit. The defective clutch is with manuafacturer for assessment wrt to a warranty claim.
Meanwhile the specialist has charged kid £200.00 labour for clutch change and is likely to be asking for a further £200.00+ for replacement clutch unit if the manufacturer deems the clutch hasn't failed through a manufacturing defect.
So my questions:
Anyone care to speculate on the likely cause of failure - specialist claims that he hasn't seen such a failure ever.
Is there anything that the specialist might have missed out wrt fitting clutch that might contributed to the failure?
If you had paid a repairer close to £500.00 6 months and less than 3k miles ago for a clutch change would you expect to have to pay again for a replacement? Just the labour or replacement parts cost or both?
Specialist is avoiding questions on what warranty he provides.
There are other issues with the specialist that are making me nervous, I'll no go into that just now.
Thoughts, opinions and guidance gratefully recieved
Trying to avoid my kid getting a financial caning IF he's in the right.
Story, in April a BMW specialst changed the clutch on his E36 M3, in less than 3k miles the clutch has failed catastrophically - the pressure plate drive face (not the friction plate) has broken into 4 pieces. I understand that an OE quality full clutch assembly had been fitted inc a "guide tube"
The broken pieces had some signs of blueing - not heavy, but obviously some heating of the drive surface occured.
At the time of failure (couldn't change gear) I'm assured the car wasn't being driven hard, I believe him - he's sensible, loves his car and treats it a reassuring degree of mechanical sympathy Up until the time the clutch failed everything worked normally; no slippage and easy gear changes.
When no gears could be selected (changing from 5th to 4th) the car was stopped and he had a look around. Nothing obvious and no smells. From standstill with engine running nothing could be selected. He managed to select 2nd gear with engine stopped, started engine with clutch depressed and some drive was evident. Released clutch and managed to drive some 12 miles home in second gear by which time there was a distinct smell of burning clutch (cause of blueing mentioned above?)
Car was rcovered to specialist who has again replaced clutch with another LuK unit. The defective clutch is with manuafacturer for assessment wrt to a warranty claim.
Meanwhile the specialist has charged kid £200.00 labour for clutch change and is likely to be asking for a further £200.00+ for replacement clutch unit if the manufacturer deems the clutch hasn't failed through a manufacturing defect.
So my questions:
Anyone care to speculate on the likely cause of failure - specialist claims that he hasn't seen such a failure ever.
Is there anything that the specialist might have missed out wrt fitting clutch that might contributed to the failure?
If you had paid a repairer close to £500.00 6 months and less than 3k miles ago for a clutch change would you expect to have to pay again for a replacement? Just the labour or replacement parts cost or both?
Specialist is avoiding questions on what warranty he provides.
There are other issues with the specialist that are making me nervous, I'll no go into that just now.
Thoughts, opinions and guidance gratefully recieved
jac-in-a-box said:
Need a little help guys - and excuse my poor clutch terminology that follows!
Trying to avoid my kid getting a financial caning IF he's in the right.
Story, in April a BMW specialst changed the clutch on his E36 M3, in less than 3k miles the clutch has failed catastrophically - the pressure plate drive face (not the friction plate) has broken into 4 pieces. I understand that an OE quality full clutch assembly had been fitted inc a "guide tube"
The broken pieces had some signs of blueing - not heavy, but obviously some heating of the drive surface occured.
At the time of failure (couldn't change gear) I'm assured the car wasn't being driven hard, I believe him - he's sensible, loves his car and treats it a reassuring degree of mechanical sympathy Up until the time the clutch failed everything worked normally; no slippage and easy gear changes.
When no gears could be selected (changing from 5th to 4th) the car was stopped and he had a look around. Nothing obvious and no smells. From standstill with engine running nothing could be selected. He managed to select 2nd gear with engine stopped, started engine with clutch depressed and some drive was evident. Released clutch and managed to drive some 12 miles home in second gear by which time there was a distinct smell of burning clutch (cause of blueing mentioned above?)
Car was rcovered to specialist who has again replaced clutch with another LuK unit. The defective clutch is with manuafacturer for assessment wrt to a warranty claim.
Meanwhile the specialist has charged kid £200.00 labour for clutch change and is likely to be asking for a further £200.00+ for replacement clutch unit if the manufacturer deems the clutch hasn't failed through a manufacturing defect.
So my questions:
Anyone care to speculate on the likely cause of failure - specialist claims that he hasn't seen such a failure ever.
Is there anything that the specialist might have missed out wrt fitting clutch that might contributed to the failure?
If you had paid a repairer close to £500.00 6 months and less than 3k miles ago for a clutch change would you expect to have to pay again for a replacement? Just the labour or replacement parts cost or both?
Specialist is avoiding questions on what warranty he provides.
There are other issues with the specialist that are making me nervous, I'll no go into that just now.
Thoughts, opinions and guidance gratefully recieved
The broken pressure plate is almost certainly due to microslip due to a loss in clamp load. Faulty fitting and grease everywhere would see a differnt failure mode.Trying to avoid my kid getting a financial caning IF he's in the right.
Story, in April a BMW specialst changed the clutch on his E36 M3, in less than 3k miles the clutch has failed catastrophically - the pressure plate drive face (not the friction plate) has broken into 4 pieces. I understand that an OE quality full clutch assembly had been fitted inc a "guide tube"
The broken pieces had some signs of blueing - not heavy, but obviously some heating of the drive surface occured.
At the time of failure (couldn't change gear) I'm assured the car wasn't being driven hard, I believe him - he's sensible, loves his car and treats it a reassuring degree of mechanical sympathy Up until the time the clutch failed everything worked normally; no slippage and easy gear changes.
When no gears could be selected (changing from 5th to 4th) the car was stopped and he had a look around. Nothing obvious and no smells. From standstill with engine running nothing could be selected. He managed to select 2nd gear with engine stopped, started engine with clutch depressed and some drive was evident. Released clutch and managed to drive some 12 miles home in second gear by which time there was a distinct smell of burning clutch (cause of blueing mentioned above?)
Car was rcovered to specialist who has again replaced clutch with another LuK unit. The defective clutch is with manuafacturer for assessment wrt to a warranty claim.
Meanwhile the specialist has charged kid £200.00 labour for clutch change and is likely to be asking for a further £200.00+ for replacement clutch unit if the manufacturer deems the clutch hasn't failed through a manufacturing defect.
So my questions:
Anyone care to speculate on the likely cause of failure - specialist claims that he hasn't seen such a failure ever.
Is there anything that the specialist might have missed out wrt fitting clutch that might contributed to the failure?
If you had paid a repairer close to £500.00 6 months and less than 3k miles ago for a clutch change would you expect to have to pay again for a replacement? Just the labour or replacement parts cost or both?
Specialist is avoiding questions on what warranty he provides.
There are other issues with the specialist that are making me nervous, I'll no go into that just now.
Thoughts, opinions and guidance gratefully recieved
The clamp load could be down to probably two things -
1) The clutch pedal return spring has broken, so there is always some load on the clutch, a bit like riding the pedal.
2) The clutch was incorrectly manufactured and could not achieve full design clamp load, so it slipped.
I'd say it sounds strongly like a manufacturing defect.
I've never come across the friction plate of a pressure plate having fractured (I assume this is the part in question), I have come across broken fingers before. However both issues are nigh on impossible to cause under normal or even abusive driving.
I've never come across the friction plate of a pressure plate having fractured (I assume this is the part in question), I have come across broken fingers before. However both issues are nigh on impossible to cause under normal or even abusive driving.
Clearly it was working ok until something failed at a specific point in time and if no gears could be selected then the clutch wasn't releasing. That's usually a fault in the operating mechanism (cable or hydraulics) rather than the clutch itself but you don't say that any part of that needed to be fixed.
Also if it was both not releasing fully and not gripping properly either then it indicates a more complex failure than just the operating mechanism. I suspect the pressure plate had already broken at that point so the release fingers couldn't operate it properly. They would neither be able to retract it or properly compress it against the friction plate because the broken bits would just splay out instead of taking the load. I can't see any reason for that happening other than a manufacturing defect and there's certainly no way the driver could cause it to happen. In fact I'm surprised that a reputable garage wouldn't just say fair cop guv and fix it and deal with the manufacturer later because it can only be down to a fitting or manufacturing problem.
What I would however suggest is you make it clear in writing asap that the parts are still your paid for property, you expect them to be returned to you and not to be destructively tested or further damaged in any way so that you can take them for an independent examination if LUK disclaim responsibility. Your claim would then be against the garage through the small claims of course, not against LUK.
Dave Baker
Puma Race Engines
Also if it was both not releasing fully and not gripping properly either then it indicates a more complex failure than just the operating mechanism. I suspect the pressure plate had already broken at that point so the release fingers couldn't operate it properly. They would neither be able to retract it or properly compress it against the friction plate because the broken bits would just splay out instead of taking the load. I can't see any reason for that happening other than a manufacturing defect and there's certainly no way the driver could cause it to happen. In fact I'm surprised that a reputable garage wouldn't just say fair cop guv and fix it and deal with the manufacturer later because it can only be down to a fitting or manufacturing problem.
What I would however suggest is you make it clear in writing asap that the parts are still your paid for property, you expect them to be returned to you and not to be destructively tested or further damaged in any way so that you can take them for an independent examination if LUK disclaim responsibility. Your claim would then be against the garage through the small claims of course, not against LUK.
Dave Baker
Puma Race Engines
Thanks for replies guys...
Yes, it is the friction drive/plate that's part of the clutch cover - 4 fractured pieces. "Fingers" on cover plate where all fine.
"Micro-slip" I assume that wouldn't be noticeable under normal driving conditions?
If the defect is agreed to be a manufacturing issue, is it reasonable to expect to have to pay for the labour in fitting the new unit - would a garage be able to claim the labour costs from the manufacturer?
If it had been done at a BMW dealer I'd imagine it would be done FOC if it was deemed the clutch was faulty?
Yes, it is the friction drive/plate that's part of the clutch cover - 4 fractured pieces. "Fingers" on cover plate where all fine.
"Micro-slip" I assume that wouldn't be noticeable under normal driving conditions?
If the defect is agreed to be a manufacturing issue, is it reasonable to expect to have to pay for the labour in fitting the new unit - would a garage be able to claim the labour costs from the manufacturer?
If it had been done at a BMW dealer I'd imagine it would be done FOC if it was deemed the clutch was faulty?
jac-in-a-box said:
Thanks for replies guys...
Yes, it is the friction drive/plate that's part of the clutch cover - 4 fractured pieces. "Fingers" on cover plate where all fine.
"Micro-slip" I assume that wouldn't be noticeable under normal driving conditions?
If the defect is agreed to be a manufacturing issue, is it reasonable to expect to have to pay for the labour in fitting the new unit - would a garage be able to claim the labour costs from the manufacturer?
If it had been done at a BMW dealer I'd imagine it would be done FOC if it was deemed the clutch was faulty?
At the risk of sounding tetchy already I'm going to have to suggest you stick to the issues that actually concern you in this and don't start wandering off into hypotheticals such as what a non existant BMW dealer who isn't involved might have done or inventing phrases such as micro-slip which no one has ever heard of and don't mean anything.Yes, it is the friction drive/plate that's part of the clutch cover - 4 fractured pieces. "Fingers" on cover plate where all fine.
"Micro-slip" I assume that wouldn't be noticeable under normal driving conditions?
If the defect is agreed to be a manufacturing issue, is it reasonable to expect to have to pay for the labour in fitting the new unit - would a garage be able to claim the labour costs from the manufacturer?
If it had been done at a BMW dealer I'd imagine it would be done FOC if it was deemed the clutch was faulty?
The clutch broke, long before it ought to have done, you have a right to expect it to be fixed FOC and if they don't then take them to the small claims court, preferably with an independent expert's opinion. That is all that ought to concern you.
Your input is appreciated Dave, thanks. I was typing my last reply while you were posting yours
You sounding tetchy? Not at all...I'm not getting sidetracked either, simply looking to understand how the failure might have occured and if possible prevent my kid being held over a barrel for a few more quid which will ineviatably come from me!
I'm certainly no mechanical whiz-kid and the term "micro-slip" was introduced by another member in a helpful fashion. I'm not familiar with it and simply asked a question from those with greater knowledge than me.
The hypothetical BMW dealer comment was in fact based on past experience - kid bought a sensor from BMW, he fited it and went duff 10 months later. BMW provided a replacement and fitted it FOC.
This really is what I'd hoped the BM specialist would do in the case of the duff clutch.
None-the-less, some good suggestions from you that will be pursued.
You sounding tetchy? Not at all...I'm not getting sidetracked either, simply looking to understand how the failure might have occured and if possible prevent my kid being held over a barrel for a few more quid which will ineviatably come from me!
I'm certainly no mechanical whiz-kid and the term "micro-slip" was introduced by another member in a helpful fashion. I'm not familiar with it and simply asked a question from those with greater knowledge than me.
The hypothetical BMW dealer comment was in fact based on past experience - kid bought a sensor from BMW, he fited it and went duff 10 months later. BMW provided a replacement and fitted it FOC.
This really is what I'd hoped the BM specialist would do in the case of the duff clutch.
None-the-less, some good suggestions from you that will be pursued.
Edited by jac-in-a-box on Friday 24th October 13:22
Edited by jac-in-a-box on Friday 24th October 13:24
wildoliver said:
I'd say it sounds strongly like a manufacturing defect.
I've never come across the friction plate of a pressure plate having fractured (I assume this is the part in question), I have come across broken fingers before. However both issues are nigh on impossible to cause under normal or even abusive driving.
I've never come across the friction plate of a pressure plate having fractured (I assume this is the part in question), I have come across broken fingers before. However both issues are nigh on impossible to cause under normal or even abusive driving.
I have never seen this kind of failure either in all my years in the workshop,it could well be a manufacturers fault,not sure i like the sound of the bluing that would indicate slippage 
Edited by That Daddy on Saturday 25th October 12:56
jac-in-a-box said:
Thanks for replies guys...
Yes, it is the friction drive/plate that's part of the clutch cover - 4 fractured pieces. "Fingers" on cover plate where all fine.
"Micro-slip" I assume that wouldn't be noticeable under normal driving conditions?
If the defect is agreed to be a manufacturing issue, is it reasonable to expect to have to pay for the labour in fitting the new unit - would a garage be able to claim the labour costs from the manufacturer?
If it had been done at a BMW dealer I'd imagine it would be done FOC if it was deemed the clutch was faulty?
Microslip is not noticeable, because the amount is small, but it gets heat into an area that can't get rid of the heat. Yes, it is the friction drive/plate that's part of the clutch cover - 4 fractured pieces. "Fingers" on cover plate where all fine.
"Micro-slip" I assume that wouldn't be noticeable under normal driving conditions?
If the defect is agreed to be a manufacturing issue, is it reasonable to expect to have to pay for the labour in fitting the new unit - would a garage be able to claim the labour costs from the manufacturer?
If it had been done at a BMW dealer I'd imagine it would be done FOC if it was deemed the clutch was faulty?
Even if the issue was a manufacturing one (say diaphragm spring low on thickness and therefore weak, pivot in wrong place) the supply contract may be one of no warranty. A lot of OE contracts are like that.
If the part had been replaced at the dealer it would probably be replaced free of charge.
But back to the issue - you MUST check the pedal return spring, they DO break and they DO allow microslip to take place.
While I understand you may find this difficult to take in, you have to understand I worked as a Clutch & Manual Transmission Engineer for one of the "Big 3", have seen all sorts of different failures and this seems to be the most likely to me.
At a guess the bluing could very well have been caused from the drive home with the fractured plate, I can't believe it was holding the friction plate well so will have slipped a little (a lot).
I guess the sad thing (and I speak as a garage myself) is that the mechanic is likely to lose out, I can see the manufacturer being difficult and he'll really have to fight to get his labour back I reckon.
I guess the sad thing (and I speak as a garage myself) is that the mechanic is likely to lose out, I can see the manufacturer being difficult and he'll really have to fight to get his labour back I reckon.
Again, thanks for your further replies.
Clutch return arrangements are fine - I can see what you mean about micro slip now!
The specialist hasn't lost out on the labour, my kid has already paid for it; the car is up and running on its 2nd clutch, it's the prospect of potentially having to pay up for a second clutch, as well that's sticking in his throat. So far it's £750 with another couple of hundred on the the horizon.
We'll just have to wait and see what comes of the manufacturer's investigations, which will then, apparently, be passed to the motor factor who supplied the original clutch and onwards to the specialist...then we'll see what happens.
Had a call from the specialist to ask what sort of flywheel(dual mass or solid) is fitted to the car FGS!!...theyr're all DM flywheels AFAIK
I mean this guy is a BMW "specialist" I'm just nervous that there may be a little scope for dishonesty to creep in.
Clutch return arrangements are fine - I can see what you mean about micro slip now!
The specialist hasn't lost out on the labour, my kid has already paid for it; the car is up and running on its 2nd clutch, it's the prospect of potentially having to pay up for a second clutch, as well that's sticking in his throat. So far it's £750 with another couple of hundred on the the horizon.
We'll just have to wait and see what comes of the manufacturer's investigations, which will then, apparently, be passed to the motor factor who supplied the original clutch and onwards to the specialist...then we'll see what happens.
Had a call from the specialist to ask what sort of flywheel(dual mass or solid) is fitted to the car FGS!!...theyr're all DM flywheels AFAIK
I mean this guy is a BMW "specialist" I'm just nervous that there may be a little scope for dishonesty to creep in.
GavinPearson said:
The 'specialist' probably knows how to change the oil on a 316 or 525 but I think that is probably the limit of his 'expertise'.
You might want to avoid him in the future.
He doesn't - that falls undeer the area of concerns I alluded to earlier. He was 2 ltrs short during an oil service at the time he did first clutch...when I asked, he replied "I thought that was all it took"You might want to avoid him in the future.
For sure, he's had one bite of the cherry - he'll not be getting another.
jac-in-a-box said:
GavinPearson said:
The 'specialist' probably knows how to change the oil on a 316 or 525 but I think that is probably the limit of his 'expertise'.
You might want to avoid him in the future.
He doesn't - that falls undeer the area of concerns I alluded to earlier. He was 2 ltrs short during an oil service at the time he did first clutch...when I asked, he replied "I thought that was all it took"You might want to avoid him in the future.
For sure, he's had one bite of the cherry - he'll not be getting another.
rest assured LUK will find out whos to blame.GavinPearson said:
That Daddy said:
The cause of clutch failure may be in that last post somewhere rest assured LUK will find out whos to blame.
I think that the odds are that LuK will say it isn't their fault. rest assured LUK will find out whos to blame.So far, earlier posts suggest that failure is unlikely to be caused by aggressive driving - which I'm confident is not the case.
I really need to know what stance to adopt should the specialist be asking for further ££'s...I'll seek advice from CAB, but would be eager to hear the views of contributors to this thread.
GavinPearson said:
That Daddy said:
The cause of clutch failure may be in that last post somewhere rest assured LUK will find out whos to blame.
I think that the odds are that LuK will say it isn't their fault. rest assured LUK will find out whos to blame.
Edited by That Daddy on Monday 27th October 09:46
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