[nzenigma]

Would be great to hold a "diesel vibration experience" weekend.   
  I've lost the plot   

They have reserved a room for you on the 2nd floor of the Asylum . Same as me! 

Unfortunately, 3rd floor with the best views is full of nutters from Facebook; aka "the echo chamber".

[nzenigma]

I had this on my FD just before it's 5th birthday (5 years ago).  1800-2000rpm rattle/vibration only in 4th/5th/6th.

IIRC they replaced the flywheel and the noise remained.
They then replaced the clutch and all was good.
I seem to recall they believed it was an issue with springs in the clutch.

I only quote you Lorian so that I can demonstrate why @mickd  and I are in wards 2/34 & 2/35.

 If there is any logic to springs causing vibration it escapes me.

Calculations:

 A 10 kilogram, 300mm  flywheel rotating at 2000 rpm  develops a centrifugal force of 6,711 kilograms.
10 clutch springs with a combined weight of about 100 grams rotating at 2000 rpm develop a centrifugal force of 27 kilograms.

Thats about 200% difference.

Furthermore, the springs travel at 1/3 the speed of the flywheel; however, even at a mere 12.5 metres/second, they are not capable of moving.

And we are asked to believe that this can cause the whole car to vibrate.   

[Dazzler]

@nzenigma With respect Gary, a tiny little lead weight can stop a wheel and tyre vibrating, so maybe your theory is crap. Just saying.. 

[nzenigma]

@nzenigma With respect Gary, a tiny little lead weight can stop a wheel and tyre vibrating, so maybe your theory is crap. Just saying.. 

@Dazzler  with respect, the lead weight is spinning at the same rate as the wheel.

@Dazzler  with respect explain to YOUR members why the clutch replacement rarely  solves the vibration/harmonic issue. 

@Dazzler  with respect explain why the 'spring vibration' is limited to the diesel motor, not manual petrol motors. 

[tw2005]

Would be great to hold a "diesel vibration experience" weekend.   
  I've lost the plot   

They have reserved a room for you on the 2nd floor of the Asylum . Same as me! 

Unfortunately, 3rd floor with the best views is full of nutters from Facebook; aka "the echo chamber".

I 'm not finished with my room yet gents. You'll have to get in line

[Dazzler]

 

[mickd]

Would be great to hold a "diesel vibration experience" weekend.   
  I've lost the plot   

They have reserved a room for you on the 2nd floor of the Asylum . Same as me! 

Unfortunately, 3rd floor with the best views is full of nutters from Facebook; aka "the echo chamber".

I 'm not finished with my room yet gents. You'll have to get in line

 
I'm, a, happy little fruitcake ,
as nutty as can be,
diesel vibrations are the end of me,
they've put me in a straight jacket
and  now I need to pee  !!

 

[nzenigma]

From my room you can hear    

At my window I can see my reflection 

When I'm quiet I calculate stuff    

Sometimes we are allowed to watch the 3rd floor echo chamber 

All this pleasure because of  SRINGS. It can be yours too!

[nzenigma]

 I 'm not finished with my room yet gents. You'll have to get in line

Wow, imagine having the whole basement to yourself 

 

[nzenigma]

@nzenigma With respect Gary, a tiny little lead weight can stop a wheel and tyre vibrating, so maybe your theory is crap. Just saying.. 

 Actually @Dazzler , old mate,  during this clueless meander you touch upon an important point. 

The flywheel is similarly balanced during manufacture; not by adding weight, but by machining metal off it. Like an undamaged wheel, the flywheel's balance remains perfect.
Clutch springs also remain at  their original meager weight, irrespective of tension.

If you missed my edit above, my 'crap theory' is only discussed when talking about diesel not petrol ??????

[Lorian]

And we are asked to believe that this can cause the whole car to vibrate.   

Ah well, thankfully I don't give a frig, I was just quoting my experience and what I recall the dealer saying over 5 years ago in the hope it might help someone.

[BrendanP]

Having read all this lot, doesn't this sound like a DMF problem? There's part of the flywheel driven by the crankshaft, and another part of the flywheel that drives the clutch plate. Between the two parts of the flywheel there is a flexible coupling, which I presume contains springs and dampening material. The whole point of the DMF is to reduce vibration from the engine being transmitted through to the gearbox. Like any system containing mass, dampening and elasticity, resonance will occur at particular frequencies. As the flywheel ages and the damping becomes less effective as rubber parts get harder or start to crack, and the springy parts get tired, the resonant frequency will change to the point where it coincides with engine vibration at a particular rev band. The resonance amplifies the vibration instead of dampening it.

The two parts of the flywheel don't just rotate together at crankshaft speed, they also rock back and forth relative to each other. When they get worn it's this slop between the two halves that leads to excessive vibration. Not a clutch issue.

[dereknunn]

I was assured by the Hyundai dealership who replaced my clutch under warranty that my flywheel is solid and not a dual mass item, but I know there is much conjecture on this subject too. The dealership also assured me no machining of my flywheel took place.

However, the previous DMF post together with another post about changing from an aftermarket to a genuine Hyundai clutch stopping the vibration got me thinking that perhaps the Hyundai clutch plate is not flawed as I was believing, and that maybe the clutch springs becoming loose and rattling are actually caused by an underlying issue; that is to say they are a symptom and not the cause.

In my case a replacement clutch stopped the vibration / rattle completely, but only for 60,000km, exactly the same time it took the original occurrence of the problem to manifest.

So, is it possible that the springs in a new clutch plate, be it of Hyundai or aftermarket origin, mask the vibration, until such time as the underlying issue causes wear to the springs to the point that they become loose enough for the vibration to become apparent again?

As I have said before, I am neither a mechanic or a physicist, and I have no suggestions as to what this underlying issue could be, but perhaps it is relative that peak torque is generated in the noted rev range, and according to the specs, the torque output of the motor is de-rated by Hyundai when it is coupled to a manual transmission opposed to the twin-clutch variant (from GD model onward)

[nzenigma]

Between the two parts of the flywheel there is a flexible coupling, which I presume contains springs and dampening material.

No!!!! The flywheel is one solid lump of steel.

[tw2005]

 I 'm not finished with my room yet gents. You'll have to get in line

Wow, imagine having the whole basement to yourself 

 

Actually , you're genius. I believe you have enough landscape to go underground, the next bat cave.

LINK

[dereknunn]

After a little further reading and googling I am now firmly of the opinion it is NOT my loose clutch springs themselves vibrating, but instead believe they are the cause other vibrations being noticeable.

For those genuinely interested, the following link explains the role of the clutch damper assembly, and how it eliminates vibrations passing from the engine to the drive-train when the clutch is engaged.



And this link includes a rather more scientific explanation for members so inclined.

MODELLING AND EXPERIMENTAL INVESTIGATION OF CLUTCH DAMPER SPRING STIFFNESS ON TRUCK DRIVING COMFORT

This now leaves me wondering whether the vibration in my car is a fault or just a characteristic.

I guess I stick to my plan of fitting an Excedy clutch when the current Hyundai one fails and see if the springs in it last longer than 60,000km.

[nzenigma]

For those genuinely interested, the following link explains the role of the clutch damper assembly, and how it eliminates vibrations passing from the engine to the drive-train when the clutch is engaged.

  Being genuinely interested for several years  I thank you for the vid and appreciate the fact that you now realise that in this case we are not talking about the dual mass flywheel (DMF) 

Given that most drivers have limited technical knowledge it is difficult to fully separate the many reported transmission and damper faults from the 2000 rpm range fault.

To reiterate several years of posts on this subject, many which are also linked to this thread:

The numerous reports of clutch changes provide no clarity as to this being an effective remedy. Many report mild or no improvement in the '2000 rpm range' vibration.

With the exception of one DMF, to my knowledge no clutch/flywheel rattle at idle has ever been reported.

The Excedy clutch is a top performing device that is attempting to replicate the action of the DMF.

Dual-mass flywheel - Wikipedia

Incidentally, the more expensive DMF  has about a 5 year life span, depending on its work load. It comes with the Hyundai 7 speed DCT box.

Your video correctly gives several possible sources of vibration. One is the "loose" un-driven gears in the gear box. However, the reported i30 vibration is constant through 3rd, 4th and 5th gears, (these various loose gears are therefore being used). Using a heavier grade lubricant may resolve or simply illuminate this phenomenon.

After a little further reading and googling I am now firmly of the opinion it is NOT my loose clutch springs themselves vibrating, but instead believe they are the cause other vibrations being noticeable.

After years of further reading I have no firm opinion on the solution for the vibration .. I have a strong suspicion that it is a harmonic oscillation occurring somewhere  in the car.

Question, how do you know YOUR springs are loose?

[Dazzler]

@nzenigma Excellent post thanks Gary.

[BrendanP]

A dual-mass flywheel, by definition, consists of two masses. A flywheel which is made of one solid disc of steel is not a dual-mass flywheel, it's just a flywheel. Clutch plates also contain springs between the outer friction disc and inner splined hub which provide some torsional elasticity.

[nzenigma]

A dual-mass flywheel, by definition, consists of two masses. A flywheel which is made of one solid disc of steel is not a dual-mass flywheel, it's just a flywheel. Clutch plates also contain springs between the outer friction disc and inner splined hub which provide some torsional elasticity.

The construction and operation of the Dual Mass Flywheel (DMF) is covered above and in other threads. It is not relevant to this thread because the FD and GD crdi, with 5 & 6 speed manual box, do not employ it . As I said, they have a solid (single mass) flywheel.

[BrendanP]

I stand pleasantly corrected.

[Dazzler]

I stand pleasantly corrected.

Thank goodness!  That's how we like it. 

[dereknunn]

@nzenigma

I never thought we were talking about a DMF, and I never believed my car was so equipped, as I stated in my post. It was simply the content of the post about how a DMF works that got me thinking about the elimination of vibration in the drive-train (by the clutch).

My vibration, whilst a more common occurrence in higher gears, is certainly far more severe when it does occur in lower gears.

My vibration is no longer apparent by 2000rpm, it only occurs in the 1600 - 1900rpm range.

I confirm I have never experienced any vibration at idle.

You may well be right about a harmonic oscillation, I certainly feel it through the floor of the car more than through the gear shifter and I can certainly understand why Hyundai elected to replace the front section of the exhaust system on my car in their earlier attempts to address the problem.

All I can report with absolute certainty is the vibration was not apparent AT ALL for the first 60,000km, or for exactly 60,000km after a new genuine Hyundai clutch was fitted.

The springs in my original clutch were loose. Very loose in fact. @Dazzler kindly posted the video of them rattling around in the post below, but unfortunately the link no longer works. I probably still have the video but wouldn't know how to post it myself I'm afraid.

Transmission Vibration (Clutch issue) & Coolant Loss

I can't of course be 100% sure the springs in the replacement clutch are loose, but an identical fault after an identical mileage makes it a fairly safe assumption in my book.

If I do need to replace my clutch again I will of course report on the condition of the springs, and in due course how the Excedy item fares in comparison to the genuine Hyundai item. Unfortunately, whether that transpires to be better or worse, it seems likely the springs will give out and the vibration will return long before the clutch otherwise reaches the end of its useful life.

Your comment about lubricant is duly noted and I will mention this next time I'm talking to the service manager at my local dealer who has taken on a bit of an interest in this case himself.

[joel_t]

Thought I'd add 2c worth here. I've read plenty about the various theories and having removed my clutch over the weekend, I have another piece to add to the puzzle.

Mine is a 2013 GD diesel hatch which has always had the vibration/noise/resonance during the time I've owned it. I purchased it with about 150k on the clock and it recently clicked over 196.

There were a couple of instances in the lead up to removing the gearbox where I couldn't select a gear momentarily and on the second of those occurrences there was slippage in third. I didn't drive it again until moving it onto the hoist for repair, during which time it performed normally.

As I suspected, the clutch plate (friction plate) is what failed. The pressure plate is fine, it really could be used again (I'll replace it though) and the flywheel surface is also fine. The flywheel side of the the friction plate is not at all worn out, but the pressure plate side has totally failed (all the friction material gone) but there was a detached ring of material preventing pressure plate damage. Upon closer inspection, two of the friction plate springs contain hollow metal cylinders which are able to move freely backwards and forwards within the spring. The other two contain smaller springs and these don't appear to move.

I suspect that under certain rpm/load conditions, the metal cylinders are not in exactly the same position relevant to the other and this results in a harmonic vibration (which quite possibly is amplified by exhaust/whatever). This vibration is what caused the premature failure of the friction material one side of the friction plate only. The plate eventually shook itself to pieces. I should add that the springs themselves aren't loose really, the rattle comes from within the springs. When you rotate the plate backwards and forwards quickly, there is a noticeable change in momentum as the metal cylinders fly back and forth.

I'm really hoping that the replacement clutch doesn't contain these metal cylinders as I have no idea why they are present in the first place. I'd be interested to know how many of the replacement clutches fitted have these pieces present as this could explain why replacement clutches didn't fix the problem.

Anyway, it'll be interesting to see what happens when I put it back together over the next couple of days.

[tw2005]

That clutch plate is mind blowing, never seen anything like that and te  mountain of dust in the background I assume came out of the bellhousing. It's as if it simply disintegrated

[Dazzler]

Welcome @joel_t

Brilliant 1st post! 

[nzenigma]

@joel_t

200,000 km is fairly reasonable  life from a clutch plate, you can get more or a lot less depending on the work you give it.

The wear you see on the DRIVEN PLATE is the normal end of life. I would change the pressure plate, probably ok, but for a few more bucks you get rid of one that may be tired and has contributed to some wear.

The springs are normal to any clutch plate, despite all the pontification,  there is usually movement and the steel ( or rubber???? ) inside them is usual ,  Im not sure of its role but presume it stops the spring from distorting and compressing too far when under load.

The i30 clutch seems to last a while. On 4x4s we use excedy or similar HD because the makers generally use cheap light duty clutches which burn out quickly and help to destroy the dual mass flywheel. Most owners swap to a cheaper , last for ever, solid flywheel.