i30 Owners Club

THE GARAGE (SERVICE, MAINTENANCE & REPAIR) => GENERAL => Topic started by: stkman on October 11, 2016, 03:17:34

Title: Low clutch bite point resolution
Post by: stkman on October 11, 2016, 03:17:34
Hi All,

About a year ago when my FD 1.6 diesel i30 was at around 200,00km, the clutch bite point suddenly changed. Previously it was at around half of the available pedal stroke and suddenly was at about 30mm from the floor.
After a week or so, I took the car to my local mechanic who said the clutch was fine … ‘no issues at all’. I carried on driving. Sometimes the bite point seemed to improve a little. Although the next morning when the car was cold, it was back to being quite low.

Searching the i30 forum indicated a few have experienced something similar, sometime being resolved by bleeding the clutch, sometimes not. After putting up with a low bite point for about 8 months and 35,000 km, I took the car into the previously mentioned local mechanic for a complete clutch fluid change (and complete bleed). And afterwards … it was still the same 
Again, I left it for a while. Was getting quite good a double de-clucthing by this stage.  Eventually though, I decided this needed fixing. Off to a clutch specialist. He said the hydraulic system was the place to start as the cheapest. Noticed a weeping clutch slave cylinder. That was rebuilt, the system bled again and I picked it up expecting a vastly improved bite point. Nope, just the same. The master cylinder ‘looked OK’ according to the clutch specialists. But I decided to rebuild the master clutch cylinder (none available new in NZ and quite expensive anyway).

I decided to buy a second hand cylinder and have that rebuilt as then it was simply a swap over and bleed. Had a look at the master clutch cylinder and noticed it looked a little different to what I expected.

(http://i244.photobucket.com/albums/gg11/stkman_photos/clutch%201_zpsoiszfdln.jpg) (http://s244.photobucket.com/user/stkman_photos/media/clutch%201_zpsoiszfdln.jpg.html)

The cylinder appeared like a regular cylinder but then it went into another odd shaped device (the rusty piece in the photo). Bit of research needed here. The ‘extra’ piece is in fact a ‘clutch damper’. My research shows that this damper appears exactly the same as the one used on many models of Subaru. Its function is to slow down the clutch engagement. Initially installed in 2003 on Subaru WRXs after many customers in the US (or so the story goes) destroyed gearboxes by engaging the clutch too quickly. A diaphragm in the damper effectively puts a buffer between the clutch pedal and clutch release arm in the gearbox resulting in an engagement delay. Quite interesting as even from new, I noticed when I really wanted to go quickly (lots of revs, release clutch pedal quickly), the clutch appeared to slip for a second. I assumed it was my poor driving.

Anyway, the delayed clutch engagement is not an uncommon feature in cars these days and many do it. BMW use something they call a ‘CDV’ (clutch delay valve). Earlier Hyundais (up to 2007) used a valve in the clutch slave cylinder to do the same thing – full fluid flow when pushing down the clutch pedal and reduced flow when released.

Do these ‘dampers’ have any negative features? This is where it gets interesting. Just type ‘Subaru clutch damper delete’ into GOOGLE and read away to your hearts content. I read they can cause (especially when the diaphragm in them splits):

•   Disconnected clutch feel (whatever that means)
•   Variable bite point
•   Low bite point

Hmm, wonder if I could delete it. Asked the clutch place. Yes, they had deleted them on Subaru’s by sleeving the cylinder and not drilling the orifice through to the damper. But my i30 cylinder was different than the Subaru setup. The damper was separate from the cylinder. Looking at it, I figured it unscrewed. And so it did with a copper washer to seal it. I decided I could replace it with a bolt  with a copper washer. Measuring up the damper thread, it is M16x1.50. Figured a sump plug would possibly do the trick and GOOGLE told me some Volvo or BMW sump plugs would work. The local parts store had them by size which was even easier. I purchased an M16x1.50 sump plug which had the same thread length as the damper – how handy.

(http://i244.photobucket.com/albums/gg11/stkman_photos/clutch%202_zpsoavqnhwv.jpg) (http://s244.photobucket.com/user/stkman_photos/media/clutch%202_zpsoavqnhwv.jpg.html)

(http://i244.photobucket.com/albums/gg11/stkman_photos/clutch%203_zpscz7gojhg.jpg) (http://s244.photobucket.com/user/stkman_photos/media/clutch%203_zpscz7gojhg.jpg.html)

(http://i244.photobucket.com/albums/gg11/stkman_photos/clutch%204_zpsqfyvq6ke.jpg) (http://s244.photobucket.com/user/stkman_photos/media/clutch%204_zpsqfyvq6ke.jpg.html)


The clutch place rebuilt the cylinder, installed the sump plug in place of the damper, reassembled and bled.
So any improvement in the clutch bite point? Yes, the clutch bite point is back to where it was – half way up the pedal travel.
Reading up the effects of removing a damper it was interesting how it was on the i30. Common claims are:

•   Improved bite point (previously low, sometimes variable) … YES
•   Firmer pedal feel … NO, feels just like before
•   More direct clutch engagement … YES, let the clutch pedal out quickly and you can feel it bite, normal driving not noticeable (I have had 36 cars, all of them manuals over 40 years – have never owned an automatic). No engagement delay at all when I want to really take off quickly – just grabs and goes.
•   More direct pedal feel … MAYBE, sometimes I think I can feel some vibration in the pedal. Maybe that is the engine vibration through the clutch arm, through the hydraulic system into the clutch pedal. Possibly not as smooth as before but still a very easy clutch to use.

The big question is, was it the deletion of damper that solved this issue for me or the rebuilding of the master cylinder? The answer is that I don’t know. I could replace the bolt with the damper, re-bleed and try. And if I am back to a low bite point, can assume there is an issue with the damper  (because for 200,00 km it was fine) and replace the damper. Are they even available as a spare part?
Am I going to?  No, am pretty happy with how it is. I feel I do not need a clutch aid to use a clutch.

DISCLAIMER: I have to put this in. What I have done has worked for me. Some ‘experts’ on forums have suggested what I have done puts more strain on the clutch system and can lead to failure of parts. I can obviously offer no guarantee that if you have a low clutch bit point that this is the issue. And in the same vein, I cannot guarantee that if you do this you will not destroy your clutch completely. This post is provided by me for your  interest only.

Andrew
Title: Re: Low clutch bite point resolution
Post by: Surferdude on October 11, 2016, 05:07:47
Thanks Andrew.  Excellent post.
Title: Re: Low clutch bite point resolution
Post by: Dazzler on October 11, 2016, 05:42:42
Thanks Andrew.  Excellent post.

 :whsaid:

We must me same vintage I have been driving for 40 years and had a similar number of cars. I have had about half a dozen Autos/CVT including a work vehicle or two, but was a manual only man for about 30 years... :cool:
Title: Re: Low clutch bite point resolution
Post by: Shambles on October 11, 2016, 08:34:27
Awesome!  Thanks for such a comprehensive post :goodjob:

I think we'll put this in our Modifying section :D
Title: Re: 摇摇欲坠
Post by: The Gonz on October 11, 2016, 09:05:14
Funny, you're a shambles in any language. :lol:
Title: Re: 摇摇欲坠
Post by: CraigB on October 11, 2016, 09:11:24
Funny, you're a shambles in any language. :lol:
But in Chinese he's Crumbling :)
Title: Re: Low clutch bite point resolution
Post by: Paolo5 on October 11, 2016, 09:16:45
Thanks for the very informative post, Andrew!

 :goodjob2:
Title: Re: Low clutch bite point resolution
Post by: Paolo5 on October 12, 2016, 05:56:10
Hi Andrew,
Just curious here...how long have you been driving your i30 without the damper installed?

Cheers,
Paolo
Title: Re: Low clutch bite point resolution
Post by: stkman on October 12, 2016, 20:15:10
Hi Paolo,

Has been about 2 weeks (~1500 km) since the rebuilt cylinder without the damper was installed.

Great to have a stable bite point. Most of the time just like it was for the first 200,000km ... a nice clutch. Even better when I need to get going quickly. Clutch just bites. Nice.

270,000 km on the original clutch and works fine  :D
Title: Re: Low clutch bite point resolution
Post by: tw2005 on December 01, 2018, 08:00:11
Ol faithful been laid up for 2 weeks, gave it some work today and clutch was being a real bitch. Eventually got to the point I could not grab reverse stationary and forward gears were getting hard straining the synchros.

Thought it was time to bypass the damper valve. Used the recommended M16 x 1.5 sump plug.

REPCO RSP1009 $9 with fibr washer although there was an aluminium one under the damper valve so used that.

Quick bleed of the system and huge difference. Clutch plate now fully releases, no more grinding gears or difficult changes, bite point is at least an 25mm higher.

No noticeable difference in vibrations.

(https://www.repco.com.au/medias/A9278475-1.jpg?context=bWFzdGVyfGltYWdlc3wyODc4NXxpbWFnZS9qcGVnfHN5cy1tYXN0ZXIvaW1hZ2VzL2g0NC9oMzMvOTI1NTMxMjEzMDA3OC9BOTI3ODQ3NV8xLmpwZ3w2ZGMwNmVhOTM5ZGY4YWQxNTJlNGM4N2NmNmNmMzc5ZTQyNDI5ZjdjM2E1NzU3OTEyNmU0ZjIwYWU1ZjFhNDQ3)

416902H900
Title: Re: Low clutch bite point resolution
Post by: nzenigma on December 01, 2018, 08:31:14
Irrespective. The initial post by @stkman  should remain a benchmark.

 He he has brilliantly looked at the problem, worked through solutions, without resorting to motor-mouth reporting, and laid it out clearly  for everyone to understand.

If only there were more of you bro  :hatoff:
Title: Re: Low clutch bite point resolution
Post by: Shambles on December 01, 2018, 09:00:45
Quote from: nzenigma
The initial post by @Stikman should remain a benchmark.

You've tagged the wrong member :rolleyes:
Title: Re: Low clutch bite point resolution
Post by: stkman on December 01, 2018, 19:13:29
Irrespective. The initial post by @Stikman should remain a benchmark.

 He he has brilliantly looked at the problem, worked through solutions, without resorting to motor-mouth reporting, and laid it out clearly  for everyone to understand.

If only there were more of you bro  :hatoff:

Thanks NZ,

The solution worked for me to give me almost an extra 100,000km on the clutch. Eventually though the clutch needed replacing. Upon inspection of the old clutch I noted the throwout bearing had no lining (?plastic or teflon) and would have not been working too well. Possibly a case of overheating the clutch times as I reversed loaded trailers up my steep drive. Or just wear and tear. 292,000km out of a clutch is OK in my book though. When I replaced the clutch I left the clutch hydraulic system as is (without the damper) and am very happy.

I'm interested in seeing what the clutch setup is like in the PDi30. NZ doesn't get the manuals unfortunately ... apart from the i30N though so may pop into a dealer and have a look under the bonnet.

Glad the damper removal helped in your case.

Andrew
Title: Re: Low clutch bite point resolution
Post by: nzenigma on December 01, 2018, 20:26:52
@stkman , mate as said great report and also a testimony to the i30 clutch , as you mention reversing up the steep drive.  :rolleyes:
That is a failing with the FD crdi ( unless you were getting some lower gear in the NZ imports).

I have a steep 3.5 :1 Kiwi style driveway, bit like a Wellington street  :evil:. I cannot start in reverse when half way up it, without major burning smell and smoke.
Ive done a lot of reverse parking in Wgtn in other makes, so can imagine the i30 diesel owners spitting the dummy.
Title: Re: Low clutch bite point resolution
Post by: stkman on December 13, 2018, 08:32:12
@nzenigma , my drive is right on 3.5 to 1 as well. I think I'm getting less stupid as I get older. Since having a new clutch fitted I now don't reverse anywhere uphill (with or without trailer) if I can avoid it by turning around and letting the clutch engage at low revs and idling or powering my way up things with no clutch slip.

Yes I agree, that reverse ratio is taller than I think it should be for relaxed reversing.

Wellington streets are amazing  :D :D :D :D

Andrew
Title: Re: Low clutch bite point resolution
Post by: tw2005 on March 08, 2019, 03:54:00
@stkman

 :link: Hyundai Clutch Damper Valve - low clutch bite point / difficult gear selection (https://www.i30ownersclub.com/forum/index.php?topic=53888.new#new)
Title: Re: Low clutch bite point resolution
Post by: nzenigma on March 08, 2019, 04:41:18

Wellington streets are amazing  :D :D :D :D

Andrew

Especially on those (occasional) wet days  :rolleyes: We all just sit there spinning wheels.  Cheers Gary.  :mrgreen:
Title: Re: Low clutch bite point resolution
Post by: Th3judderman on April 16, 2019, 18:25:18
Hey first post but couldn't find a part number for the plug, gambled on this one and it works fine.
Manufacturer: Corteco
Part Number: 220137S

The mod works, but only if it's your issue. In this instance it appears it's not my issue but worth the punt for £5.
Title: Re: Low clutch bite point resolution
Post by: torbaytony on April 17, 2019, 23:46:26
What a surprize this post was. I have this problem on my I30 which used to be a police car so it could already have a new clutch in it but no record in the history. So having a very low pedal I will be looking to try this fix in the morning and will post again. Thanks for the info. Tony
Title: Re: Low clutch bite point resolution
Post by: AVP on September 24, 2019, 13:38:13
torbaytony
Well, we are still waiting...


On a side note, I have this issue on my I30 CRDI 2014 hatch, and it's only 30.000 KM (no typo). Clutch has a low bite point. I haven't noticed it before, but went to the Hyundai service and they said I need a clutch replacement (so early?) I was quite skeptical about that so I thought they are trying to rip me off. For sure the damper is the issue here as well.
Does anyone has a sketch with the cylinder/damper mechanism ?
Thanks.
Title: Re: Low clutch bite point resolution
Post by: tw2005 on September 24, 2019, 14:58:46
torbaytony
Well, we are still waiting...


On a side note, I have this issue on my I30 CRDI 2014 hatch, and it's only 30.000 KM (no typo). Clutch has a low bite point. I haven't noticed it before, but went to the Hyundai service and they said I need a clutch replacement (so early?) I was quite skeptical about that so I thought they are trying to rip me off. For sure the damper is the issue here as well.
Does anyone has a sketch with the cylinder/damper mechanism ?
Thanks.
I'm a little confused. How did you determine it was the damper? are the photos unclear?
Title: Re: Low clutch bite point resolution
Post by: tw2005 on September 24, 2019, 15:00:36
This may not be GD but it's a good indication of what you're looking at.

 :link: Hyundai Clutch Damper Valve - low clutch bite point / difficult gear selection (https://www.i30ownersclub.com/forum/index.php?topic=53888.0)
Title: Re: Low clutch bite point resolution
Post by: AVP on September 25, 2019, 09:22:24
Correct, mine is the GD, this thread was for the FD but I guess the mechanism and solution are quite the same.
I assume it is the damper as the car has only 35000 Km, I bleeded the fluid, with no results, and I am sure I am using the clutch and gearbox quite careful (it has good rpm/speed ratio, it engages very well, gears change smoothly etc.) just the byte point suddenly dropped from mid range to some 2 cm off the floor or less...   
I already ordered the damper... I might use the bolt next time (cheaper solution). Yet I shall look at your thread, @tw2005, thanks for the reply!
Title: Re: Low clutch bite point resolution
Post by: zatos99 on October 16, 2019, 04:59:01
Hey All,

Have a very similar problem with my CW, low bite point and difficulties putting her in gear. However, I have a unique situation in that my clutch and slave cylinder were just replaced. I have the sump plug ready to install that several people have used to bypass the existing damper, but before I do that I want to make sure I'm not missing anything obvious.

Cheers!
Matt
Title: Re: Low clutch bite point resolution
Post by: nzenigma on October 16, 2019, 11:37:11
Hey All,

Have a very similar problem with my CW, low bite point and difficulties putting her in gear. However, I have a unique situation in that my clutch and slave cylinder were just replaced. I have the sump plug ready to install that several people have used to bypass the existing damper, but before I do that I want to make sure I'm not missing anything obvious.

Cheers!
Matt

No not unique. Often missed. If damper is the same , do the plug trick.
Title: Re: Low clutch bite point resolution
Post by: Lorian on October 16, 2019, 19:12:09
Bleed the slave cylinder too, easy to overlook and not drained fully unless you specifically do it by pulling the clutch fork.

PD looks like it has the same damper :-(
Title: Re: Low clutch bite point resolution
Post by: zatos99 on October 17, 2019, 07:54:47
Just replaced the damper with the sump plug, works a treat. Hardly any vibrations in pedal, changes gears like new. Thanks all for help.

P.S. the Repco lady was shocked when I knew the exact part number haha
Title: Re: Low clutch bite point resolution
Post by: zatos99 on October 22, 2019, 06:12:45
Back again, unfortunately. The new sump plug is working well, but only when the car is relatively cold. When I've been driving around for a while in Sydney, it becomes difficult to change gears. I have bled the clutch 3 times now and am pretty sure it's not that.

Any suggestions?
Title: Re: Low clutch bite point resolution
Post by: nzenigma on October 22, 2019, 09:45:53
did you reverse bleed?
Title: Re: Low clutch bite point resolution
Post by: zatos99 on October 25, 2019, 08:14:12
No, I was not aware of 'reverse bleeding'. I'm guessing that is physically moving the clutch fork to draw clutch fluid into the slave? I'll have a look into it and give it a spin.
Title: Re: Low clutch bite point resolution
Post by: Paolo39 on October 25, 2019, 17:44:09
Hi Andrew,
Just curious here...how long have you been driving your i30 without the damper installed?

Cheers,
Paolo

I removed damper after having problems with gear engagement. 3 months and running fine.
Title: Re: Low clutch bite point resolution
Post by: nzenigma on October 25, 2019, 22:10:02
No, I was not aware of 'reverse bleeding'. I'm guessing that is physically moving the clutch fork to draw clutch fluid into the slave? I'll have a look into it and give it a spin.

Not exactly. Instead of pumping out the clutch bleed nipple, you force fluid in there. The best method has been to run a clear tube from nearest brake nipple to clutch nipple. Open both and pump the brake. Grab an attractive passerby to press brake while you watch underneath .... :rolleyes: .....the car.
Title: Re: Low clutch bite point resolution
Post by: Dazzler on October 26, 2019, 10:50:40
No, I was not aware of 'reverse bleeding'. I'm guessing that is physically moving the clutch fork to draw clutch fluid into the slave? I'll have a look into it and give it a spin.

Not exactly. Instead of pumping out the clutch bleed nipple, you force fluid in there. The best method has been to run a clear tube from nearest brake nipple to clutch nipple. Open both and pump the brake. Grab an attractive passerby to press brake while you watch underneath .... :rolleyes: .....the car.

I might actually grow to like you one day Gary..  :snigger: :goodjob:
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