clutch damage

[banhama]

PS. Maybe a silly question, but could the lightweight flywheel be anything to do with it?
If for some reason it was thicker, or sat a few millimetres closer to the gearbox, would it effectively cause overtravel of the fork, forcing the bearing too far into the springs?
Given that the fork travel is correct according to the manual, would any movemet of the clutch cover plate nearer the fork could cause damage? Or does the fork and cable have enough play that the bearing will just slide back along the guide tube ( gearbox shaft sleeve or whatever it's called ) to compensate?
This is starting to hurt my tiny brain now!

 

[NorthloopCup]

PS. Maybe a silly question, but could the lightweight flywheel be anything to do with it?
If for some reason it was thicker, or sat a few millimetres closer to the gearbox, would it effectively cause overtravel of the fork, forcing the bearing too far into the springs?
Given that the fork travel is correct according to the manual, would any movemet of the clutch cover plate nearer the fork could cause damage? Or does the fork and cable have enough play that the bearing will just slide back along the guide tube ( gearbox shaft sleeve or whatever it's called ) to compensate?
This is starting to hurt my tiny brain now!

If it’s the flywheel, it’s the first one I’ve seen. If it’s a clutch issue, I don’t have enough fingers to count on the amount of issues I’ve seen with them. Lol

 

[Robbie Corbett]

The old LUK plate had written on it 'gearbox side', the new valeo one didn't have anything written on it, but the two sides were obviously different and pretty much identical to the LUK one, so i fitted it the same way round. The 'gearbox side' sticks out a bit more than the flywheel side, so not sure it would have fitted the other way round. I hope that's right.

I will let you know what I find tomorrow.

Thanks all for the help

I don't think they fit the wrong way round. I certainly noticed a difference when fitting mine and you could work out which way round they should go.

 

[Robbie Corbett]

PS. Maybe a silly question, but could the lightweight flywheel be anything to do with it?
If for some reason it was thicker, or sat a few millimetres closer to the gearbox, would it effectively cause overtravel of the fork, forcing the bearing too far into the springs?
Given that the fork travel is correct according to the manual, would any movemet of the clutch cover plate nearer the fork could cause damage? Or does the fork and cable have enough play that the bearing will just slide back along the guide tube ( gearbox shaft sleeve or whatever it's called ) to compensate?
This is starting to hurt my tiny brain now!

If your flywheel is too thick, moving the whole assembly further into the box, then for the same clutch arm travel I guess you could end up with the pressure plate touching the clutch cover. Does seem a bit extreme though!

Any chance you can get someone to push the clutch in and out while you look through the doom hole?

Do you still have the old flywheel to measure?

Not sure if this is even possible, but is the fork the correct way round, I know on other cars its possible to install the fork the wrong way round, can't remember if you can on these....

 

[Robbie Corbett]

The bearing was the new one that came with the valeo kit.
As for fitting correctly, I think so, but could easily have cocked something up! From memory:
Having fitted the clutch and removed the plastic alignment tool I greased the gearbox shaft sleeve with the grease that came with the kit. The sleeve looked in good condition, no cracks or anything.
Then slid the bearing onto the sleeve, located the end of the fork into the plastic lugs.
I think then I loosely wired the top of the fork to the aperture in the casing, to keep the bearing held back on the sleeve so it didn't try to slide off the shaft as I offered the gearbox up.
Gearbox shaft seemed to locate really nicely through the clutch and everything pushed together more easily than I expected, I was ready for more of a battle and excessive swearing!
Once all that was bolted and torqued up I held the fork, cut off the wire, located the dimple in the fork on the rubber pivot, pulled the c;utch cable to full extend and hooked it back onto the fork.
Measured the travel at the top of the fork with the clutch depressed, much the same as it is now, maybe 30mm rather than 28, but still all within range I think.
After that road test etc, all seemed ok.

Even now the fork, bearing, lugs etc all feel connected as they should be.
I've tried to take a photo through the aperture and I think it still shows the bearing correctly located on the spring fingers, but PLEASE if you spot anything wrong in the photo or what I,ve said above please let me know, I definitely don't want to make the same mistake twice!

View attachment 1497220

View attachment 1497221

Many thanks
Andy

In these pictures is the clutch pedal pushed in?

I just checked some pics I have and your arm (from what I can see) is the correct way round but seems to be at the wrong angle (if the cable is on and pedal is not pushed in).

Bit hard to tell due to the angle but mine looks like its coming straight out the box.

I'm guessing your are either holding the arm or someone is pushing the clutch in for you?

 

[Robbie Corbett]

If it’s the flywheel, it’s the first one I’ve seen. If it’s a clutch issue, I don’t have enough fingers to count on the amount of issues I’ve seen with them. Lol

This would be seriously unlucky - there must be an issue somewhere to be causing this so quickly on two completely different brands of clutch.

 

[NorthloopCup]

This would be seriously unlucky - there must be an issue somewhere to be causing this so quickly on two completely different brands of clutch.

Yes I agree, but I’ve seen more clutch failures on these cars than I’ve had hot dinners. With the gripper in there as well, everything’s under more load too.

The only one that seems to last is the Sachs clutch that pms offer. Not cheap, but it removes the common denominator for issues.

 

[Kev@KAM]

How old was the original clutch plate? People do like to reuse them when fitting helix clutch plates rather than replace so fatigue is possible but rare.
I personally use Loctite on parts. I also prefer to replace bolts too as these cars are old and I dont know history of little items like clutch bolts.
Did you mark the flywheel where the original failure was? Have you checked the thread condition to make sure they are not damaged?

K.

 

[banhama]

In these pictures is the clutch pedal pushed in?

I just checked some pics I have and your arm (from what I can see) is the correct way round but seems to be at the wrong angle (if the cable is on and pedal is not pushed in).

Bit hard to tell due to the angle but mine looks like its coming straight out the box.

No @Touring_Rob the clutch pedal is up, cable attached, I'm not pulling the fork back or anything........so I think you are onto something here!
I think the bearing has pushed or ground itself into the spring fingers, the cable ratchet has self adjusted so I still get the fork travel, but all I'm getting from the spring is a bit of movement between partly engaged and partly released. If that makes any sense.

Haven't had much time today but I did get the magnet in there and it didn't pick up any of that debris on the bearing, but the movement did clear some off. So whatever it is it's probably not ferrous, which from what @NorthloopCup has said that's not a good thing!

So I need a bit of release bearing education here:
This is a picture of the old LUK bearing, which looks identical to the Valeo one and also looks in good condition.

So the inner shiney ring spins round, but the black rubber bit and outer shiney bit don't.
So the bearings are behind the rubber bit I guess.
So in my brain the only part that can touch the spring fingers is the inner rotating part, if the rubber face or outer metal part came into contact with the springs rotating at thousands of RPM then either the springs would grind away, the fixed ring of the bearing would grind away, or the whole lot would be ripped off the plastic lugged part, sending the fork into orbit.

So in this picture it looks like the outer fixed ring is in contact with the springs, is this correct?

Where has the rotating part the bearing gone, it looks like it's pushed through the springs.

Or am I talking complete ballcocks as usual!.

PS out of interest I took the cable off the fork, and then tried to use the fork to push the bearing away from the springs, down the sleeve towards the gearbox but it wouldn't budge. Should the bearing move easily away from the springs?

 

[banhama]

How old was the original clutch plate? People do like to reuse them when fitting helix clutch plates rather than replace so fatigue is possible but rare.
I personally use Loctite on parts. I also prefer to replace bolts too as these cars are old and I dont know history of little items like clutch bolts.
Did you mark the flywheel where the original failure was? Have you checked the thread condition to make sure they are not damaged?

K.

Thanks for the reply.
I can only assume the LUK clutch was a complete kit, as it was fitted by a garage, but being the first replacement on the car I guess that anything re-used would have an OEM Valeo marking, but it was all LUK
The current failure is a complete Valeo kit from @renaultpartsdirect, but using yhe old bolts as they don't come with the kit. I'm almost certain the 6 clutch cover bolts are the originals. The condition of the bolts was good when I re-used them, all torqued up fine, but it is always possible the threads area bit stretched.
I didn't even think of marking the flywheel at the time, assuming a new clutch would be the fix. Would have been a bloody good idea in hindsight though!
When I get the gearbox off, if I find the bolts have come loose I will kick myself very hard for not getting new ones.

 

[JamesBryan]

The release bearing should move back fairly easily I would imagine.

Sounds like yours has seized itself in place for some reason.

 

[banhama]

Yes I agree, but I’ve seen more clutch failures on these cars than I’ve had hot dinners. With the gripper in there as well, everything’s under more load too.

The only one that seems to last is the Sachs clutch that pms offer. Not cheap, but it removes the common denominator for issues.

I can feel that the Gripper is letting me put a whole lot more load through the transmission, as I can get on the acceleartor so much earlier in the corners. A lot of the time I am accelerating against the tyre angle, pushing them across the tarmac, which must load back through the transmission. That's with List C tyres, so will be worse with slicks.
But it's a very effective way of getting a good lap time in a low powered car!
If it turns out the standard clutch can't take my abuse, but the Sachs upgrade can, I would happily pay the premium. Just need to be sure that's the fix before shelling out £500!

This is a link to one of last Saturdays sessions, not my best one, nor unfortunately the one where the clutch failed as the camera battery had also failed by then!
Please feel free to criticise my downshifts, upshifts, abuse of the rev limiter (yes I know I need to get that adjusted or just take my foot off the gas), or anything else that might help me get to the root of this problem.
Also apologies for the poor video quality, looks better on a TV than a PC.
Oh, also apolgise for the state of the interior......it's a work in slow progress!

 

[banhama]

The release bearing should move back fairly easily I would imagine.

Sounds like yours has seized itself in place for some reason.

Thank you James, confirms what I was guessing at.
All will be revealed when I get the gearbox out i guess

 

[JamesBryan]

You love that limiter don't you 😂

If it's still on standard valves I would strongly advise not to bounce of it like that haha.

Possibly practice some heel and toe rev matching on the downshift to be kinder to the drivetrain.

 

[Robbie Corbett]

I'll try and take some pictures of mine this weekend Andy, just fitted the same clutch kit as you.

It looks to me as if the release bearing is compressing the spring plate too much (too much preload), when the clutch is pressed the pressure plate is contacting the clutch cover and levering it away from the flywheel which would fatigue mounts very quickly.

For me this is confirmed when looking at your low miles LUK clutch look at the wear to the ends of the spring fingers where the release bearing has been in contact. Compared to a picture of my old clutch which I believe to be origional to the car so 78k miles at the time of removal. You can see silver patches but I can't see actual wear to the fingers in the same way as I can on yours.

A thicker flywheel/clutch stack would move the clutch further into the bell housing, this (with no cable attached) should move the tip (where cable connects) of your clutch release fork arm towards the engine (further away from the cable. So either the assembly is being preloaded when you attach the cable (due to wrong stack height) OR the issue is with cable/pedal assembly - where the flywheel/clutch is at the correct height but the cable is too short or quadrant not resetting....

That would be my immediate guess.

From memory (insert correct measurments) the clutch fork is approximately 30cm long, its pivot is approximately 10cm away from the release bearing so a stack height error of 5mm would yield an end (of fork) movement of 10mm - from your picture is looks like your arm is that or more than this picture of my car

So if it is a flywheel issue you would be looking for thickness errors in the +5-+10mm range at a (big) guess. ie, too much for the quadrant to adjust for.....

Rob,

 

[banhama]

Possibly practice some heel and toe rev matching on the downshift to be kinder to the drivetrain.

My problem with heel and toe is very much like left foot braking, I practice and it's all great. Then I get on track and it all goes to pot!
Also I have tiny feet, no excuse, but I could do with a little extension peg on the trottle pedal, is such a thing available of the shelf? I ended up making one for my Impreza rather than buying a whole set of pedals, so I should really do the same for the Clio.

 

[Robbie Corbett]

For clarity, when the LUK clutch was installed what else was changed was it just the flywheel or was it also the clutch cable?

 

[Krarl]

My problem with heel and toe is very much like left foot braking, I practice and it's all great. Then I get on track and it all goes to pot!
Also I have tiny feet, no excuse, but I could do with a little extension peg on the trottle pedal, is such a thing available of the shelf? I ended up making one for my Impreza rather than buying a whole set of pedals, so I should really do the same for the Clio.

@andy_con laser cuts pedals for heel and toe

 

[Robbie Corbett]

You love that limiter don't you 😂

If it's still on standard valves I would strongly advise not to bounce of it like that haha.

Possibly practice some heel and toe rev matching on the downshift to be kinder to the drivetrain.

The last (and most fun) bit of track tuition I got was in a TVR and the instructor shouted at me every time I rev matched. I was obviously hoping to impress with my epic mechanical sympathy, heel and toe action but he couldn't have cared less (not his car I guess). tbf to him he was right in the sense that just smashing it into gear let me concentrate on everything else much more and if you've got time to rev match then you had time to be on the brakes harder and later....

Not sure I do fully agree with that but its being taught

 

[banhama]

For clarity, when the LUK clutch was installed what else was changed was it just the flywheel or was it also the clutch cable?

Just the flywheel, no cable, but also to note this was when the gripper diff was fitted.
So in a nutshell I was running 128,000 mile clutch on original flywheel and gearbox and getting really frustrated with the lack of drive out the corners, having previously been pampered in a 4WD, tricky diff 460bhp Impreza.
So got a recon gearbox and Gripper diff from Mark, and as I was getting a garage to do the work got new clutch (should have specified OEM) and I supplied the PMS lightweight flywheel. Probably too many drivetrain mods at one time, but when your having the gearbox out it makes financial sense. However it is still the original cable and pedal assembly.
Are you thinking the cable itself could be an issue?

 

[banhama]

@andy_con laser cuts pedals for heel and toe

Many thanks I will get in touch with him

 

[Robbie Corbett]

Just the flywheel, no cable, but also to note this was when the gripper diff was fitted.
So in a nutshell I was running 128,000 mile clutch on original flywheel and gearbox and getting really frustrated with the lack of drive out the corners, having previously been pampered in a 4WD, tricky diff 460bhp Impreza.
So got a recon gearbox and Gripper diff from Mark, and as I was getting a garage to do the work got new clutch (should have specified OEM) and I supplied the PMS lightweight flywheel. Probably too many drivetrain mods at one time, but when your having the gearbox out it makes financial sense. However it is still the original cable and pedal assembly.
Are you thinking the cable itself could be an issue?

No, not if it's the original.

Either your quadrant adjuster is fully adjusted out (you've checked that) or the flywheel is too thick. They are the two main thoughts I have.

 

[Andy_con]

@andy_con laser cuts pedals for heel and toe

 

[banhama]

The last (and most fun) bit of track tuition I got was in a TVR and the instructor shouted at me every time I rev matched. I was obviously hoping to impress with my epic mechanical sympathy, heel and toe action but he couldn't have cared less (not his car I guess). tbf to him he was right in the sense that just smashing it into gear let me concentrate on everything else much more and if you've got time to rev match then you had time to be on the brakes harder and later....

Not sure I do fully agree with that but its being taught

OUCH! But there's something in that. I'm no Aryton Schuhamilton who can do 15 different driving tasks exceptionally well whilst composing an aria.
I do aim to drive with mechanical sympathy, but spotting the braking point, hitting it, braking just enough while changing down, spotting the apex, actually aiming at it, accelerating, hittting the apex and not running straight off track, that's about 6 things in a second! Add in left foot braking and heel and toe and I'm definitely out of my multitasking range!
If I am abusing the clutch to the point of destruction my easiest solution might be as per TRV instructor, keep on abusing and just get a stronger clutch! Although that does still go against the grain

 

[banhama]

View attachment 1497436

View attachment 1497437

I would like some of those please!
Could you pm me price, payment details etc.
Many thanks, Andy

 

[JamesBryan]

The last (and most fun) bit of track tuition I got was in a TVR and the instructor shouted at me every time I rev matched. I was obviously hoping to impress with my epic mechanical sympathy, heel and toe action but he couldn't have cared less (not his car I guess). tbf to him he was right in the sense that just smashing it into gear let me concentrate on everything else much more and if you've got time to rev match then you had time to be on the brakes harder and later....

Not sure I do fully agree with that but its being taught

I think most instructors are like that initially, they want you to get the basics right so that you're in control of the car.

They don't want to be in a precarious position when you're balancing on the brakes and blipping the throttle.

In RWD cars it's even more important I think to prevent the rears from locking up. You see it happen occasionally on track, especially in the wet.

 

[Robbie Corbett]

I think most instructors are like that initially, they want you to get the basics right so that you're in control of the car.

They don't want to be in a precarious position when you're balancing on the brakes and blipping the throttle.

In RWD cars it's even more important I think to prevent the rears from locking up. You see it happen occasionally on track, especially in the wet.

Yea maybe, although his line was that there was no room for mechanical sympathy in racing. His point was that I could brake harder and later etc. Which did certainly work lap time wise. Locked up the rear quite a few times when hard on the brakes and his opinion on heel and toe remained negative. Which having had predominantly rwd cars and bikes feels dead wrong. Locking the rear on a bike is a disgusting feeling especially when your already trying hard to scrub off speed for a fast approaching corner 😂

I think it really comes down to hire car vs. your car tbh. Anyway, sorry to push this off topic.

Andy do you have a set of Vernier calipers a and your original flywheel? I think you will need to be taking a few measurements when you come to do this again.

By the weekend I'll have some photos showing the release bearing location in my car, I think it would also be informative for me to disconnect my clutch cable at the gearbox end and to measure the cable from its end to the sheath (or some fixed location) to rule that out.

 

[banhama]

Unfortunately I don't have the original flywheel, must have gone in the garage scrap bin!
I'll see if I can find the specs for OEM.
Though I'm thinking if Pure Motorsport sell a lot of these it would be more of a common issue though!
Once I've got the thing out and confirmed that it's a release issue I can see me dismantling the pedal mechanism rather than just checking that is all looks to be operating correctly.

Looking forward to photos and measurements @Touring_Rob

Thanks all for your help, much appreciated.

 

[JamesBryan]

Worth giving Nick at PMS a call, he's really helpful.

He'll be able to tell you if the specs of the lightened flywheel is different to OEM.

 

[JamesBryan]

On closer inspection on the PMS website there are options for two types of flywheel.

Standard clutch and race clutch.

Assuming you have bought the standard clutch fitment option, there should be no reason it's the flywheel at fault here I'd say.

 

[Robbie Corbett]

On closer inspection on the PMS website there are options for two types of flywheel.

Standard clutch and race clutch.

Assuming you have bought the standard clutch fitment option, there should be no reason it's the flywheel at fault here I'd say.

I agree in principal but not in practice. I get lots of parts machined for work and it only takes a machine operator to make one minor mistake to end up with an offset of several mm, plus your unlikely to spot that error when the part is on the shelf. Occasionally we will pick up a part from a large batch (all other parts are fine) to discover some weird offset - usually that spoils your day because sods law says its the last one too.

 

[NorthloopCup]

I agree in principal but not in practice. I get lots of parts machined for work and it only takes a machine operator to make one minor mistake to end up with an offset of several mm, plus your unlikely to spot that error when the part is on the shelf. Occasionally we will pick up a part from a large batch (all other parts are fine) to discover some weird offset - usually that spoils your day because sods law says its the last one too.

A lot of the flywheels are cnc machined mate - they all come from ttv, and I’ve sold a lot of them without issue in the past. So if there is an issue with it, there’s 100% a batch of faulty ones out there lol

 

[Robbie Corbett]

A lot of the flywheels are cnc machined mate - they all come from ttv, and I’ve sold a lot of them without issue in the past. So if there is an issue with it, there’s 100% a batch of faulty ones out there lol

Get that and fully agree. All of my parts are CNC milled or turned. In batch of 1000 parts it's unlikely to have no errors. For example. machine operator exchanges a cutter installing 1mm further into a tool holder and don't re zero the z cal - now every face cut has a 1mm error. With modern machines that's getting rarer but it's still a much more human intensive process than many realise (and humans f**k up lol).

So I agree totally it's really unlikely but not impossible.

 

[Robbie Corbett]

Also, does anyone know the difference between the two flywheels? Andy could the company that installed your first clutch have installed the flywheel intended for the race clutch?

 

[NorthloopCup]

Also, does anyone know the difference between the two flywheels? Andy could the company that installed your first clutch have installed the flywheel intended for the race clutch?

7/14” clutch with basket, and standard clutch/cover.

 

[banhama]

Can't find the PMS invoice for the flywheel, which is odd as I have kept all other invoices for engine mounts, camber shims etc! Typical.
I think I had it delvered straight to the garage which would explain that.
99% sure it was standard as I recall telephoning before ordereing it, but I will ask PMS if they can confirm.

Stupidly I didn't check the flywheel bolts when I had the clutch out, but I'm guessing if the flywheel was loose there would be all sorts of other more disasterous things happening.
Also whatever's going on it doesn't seem to be creating any unusual noises with the engine running in neutral, or if you start in gear and lift the clutch. I would have expected some sort of rattle or grind.

 

[JamesBryan]

Yeah if the flywheel was loose you'd know about it 😂

 

[Robbie Corbett]

Can't find the PMS invoice for the flywheel, which is odd as I have kept all other invoices for engine mounts, camber shims etc! Typical.
I think I had it delvered straight to the garage which would explain that.
99% sure it was standard as I recall telephoning before ordereing it, but I will ask PMS if they can confirm.

Stupidly I didn't check the flywheel bolts when I had the clutch out, but I'm guessing if the flywheel was loose there would be all sorts of other more disasterous things happening.
Also whatever's going on it doesn't seem to be creating any unusual noises with the engine running in neutral, or if you start in gear and lift the clutch. I would have expected some sort of rattle or grind.

Copy in emails perhaps? Would be well worth asking PMS if they could give you any dimensions to measure to identify which you have. I'm slightly hoping (for your sanity) that the race clutch type is thicker so at least you know what the problem is!

 

[Kev@KAM]

Race version flywheel would not even be able to be fitted to a standard clutch cover. The race clutches are significantly smaller diameter so the bolt holes are different and the flywheel friction surface is smaller diameter to match.

 

[banhama]

Been doing some actual work these past couple of days, so haven't done anything about the clutch yet.
I guess I must have got the correct flywheel, but will contact PMS on Monday regarding the thickness.

I am seriously considering lifting the engine and geabox out this time, rather than doing everything from underneath.
The main reason being I'll get a much better look at everything, and be able to take better photos for your inspection.

I'll need to get an engine crane, but are there any big reasons why this would be a silly idea?
I have no aircon, the battery is in the car and there doesn't look like there's too much else on top to get out of the way.
I believe you can unplug the engine loom and leave it attached?
So other than that:
Remove air filter and intake pipework
Disconnect PAS pipes having drained the reservoir.
Drain coolant disconnect radiator and heater matrix hoses.
Drain my precious new Redline MT90 and remove driveshafts.
Disconnect gear linkage
Disconnect fuel rail
Unbolt exhaust manifold
Remove 4 x engine/gearbox mounts.
(Remove fire extinguisher pipework and nozzles)

Sounds simple....So what am I missing?