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Clutch Problems - Slipping and Engagement


Sheefa

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Hi all

 

Since I had my new HKS LA Twin clutch installed I have had nothing but problems with it. When I first picked up the car from SRD it drove well and engaged nicely. The journey back home was 2 1/2 hours and I was running medium boost most of the time. I only did a few motorway pulls (given the turbo upgrade!) and wasn't hard shifting on the clutch given new. By the time I got home on the drive I could barely get it into gear, especially reverse. I didn't want to force it and called Lee. It appeared "something" had moved and was causing the clutch to drag. Lee advised how to adjust it so upside down in the footwell I went and turned the push rod and engagement was smooth again and car was boosting. There was a little free play in top of pedal as required.

 

However, it's never felt 100% and quite frankly I don't think it's anywhere as nice as my old knackered clutch. Now I have a problem where on boost it starts to massively slip. I can shift normally and generally gradually get up to speed but any hard acceleration on boost (any setting) causes slippage. The clutch has probably covered around 550-600 miles max so should be bedded in nicely. Occasionally if I shift into 3rd or 4th at speed the clutch seems to lock out and I can't get the car into gear - assume this is the clutch overheating or something else.

 

The bite point is just below half way and following advice from Lee again I went upside down in the footwell and attempted to adjust the push rod. However it does appear very stiff and don't think it's moving properly. Before you ask yes I have undone the 12mm adjustment nut!

 

I shouldn't have to adjust this clutch now and given the cost of £1300+ it's a real PITA. I have spoken to two other traders/mechanics who advised they have never had to adjust a clutch since initial setup.

 

Has anyone got any other ideas on what it could be or is it just engagement/adjustment? I'm hoping the clutch isn't worn or the release bearing buggered given all parts were brand new.

 

I came across this on supra forum which is quite useful, sounds like no freeplay in pedal causing slippage but there DEFINITELY is freeplay on mine and a good amount.

 

Any advice greatly appreciate as this is properly p!ssing me off and has done for 10months now.

 

Thanks

Greg

 

 

I see alot of people asking about clutch problems and I couldn't find a thread with all the info, so I thought I post this to help some of you. If there's something wrong or missing feel free to post a comment.

 

CLUTCH SLIPPAGE

 

- no freeplay on the pedal (causes premature wear to the release bearing and disc)

- disc badly worn

- pressure plate springs weak/broken

- overheated disc

- oil soaked linings

- warped disc or pressure plate

 

CLUTCH CHATTER

 

-contaminated disc (most common)

- release finger height uneven

- broken motor mounts

- excessively worn linkage

- warped disc or pressure plate

- pressure plate springs worn/broken

- worn ball stud pivot for clutch release fork

 

CLUTCH DRAG

 

- excessive freeplay of the pedal

- excessive freeplay causes hard shifting (clutch never releases)

- warped disc or pressure plate

- clutch hub seized to input shaft

- worn pivot on release fork

- sticking pilot bearing or bushing

 

RATTLES

 

- release fork loose

- loose hub in clutch disc or broken torsion springs

- badly worn release bearing

- wear on splines (clutch hub or input shaft)

- worn transmission bearings

 

VIBRATIONS

 

- defective disc

- bent input shaft

- defective input shaft bearing

- improper assembly of clutch cover to flywheel

- flywheel/pressure plate out of balance

 

When doing a clutch job it's always good to change the pilot and throwout bearing. If using the same flywheel remember to machine it.

Edited by Sheefa (see edit history)
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This happened to me with my RPS Triple Carbon. Turned out one of the metal plates had developed a wee burr on it causing it to stick in the basket. Clutch was disassembled and the burr filed down until it slid in and out of the basket smoothly and its been 100% since!

 

 

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I would have returned it to Lee 9 months ago mate, it should not be causing this much grief

 

Yes wish I had. Lee has been trying to help, it's a fair distance away that's all so if we could resolve remotely then all good. Doesn't look like it though :(

 

This happened to me with my RPS Triple Carbon. Turned out one of the metal plates had developed a wee burr on it causing it to stick in the basket. Clutch was disassembled and the burr filed down until it slid in and out of the basket smoothly and its been 100% since!

 

Thanks. I think something has seriously moved on journey home after install. It's just never felt "good" and I've not even put it through its paces like any launches etc.

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Yes wish I had. Lee has been trying to help, it's a fair distance away that's all so if we could resolve remotely then all good. Doesn't look like it though :(

 

 

 

Thanks. I think something has seriously moved on journey home after install. It's just never felt "good" and I've not even put it through its paces like any launches etc.

To be honest its a waste of time trying to diagnose the issue without taking it apart and having a look. I don't necessarily think it has to go back to SRD. A local garage or even yourself if you are handy should be able to do it in a morning.

 

 

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Neither a local garage, nor Greg are likely to have the input shaft alignment tool for the twin plate clutch, just before someone pulls it apart and then thinks, oops ;)

 

I thought in the good old days a metal ruler was the alignment tool of choice.

 

Could be worth the OP sending a PM to Jackyboi who was seeing a HKS duel alignment tool last November so probably now has the required tool lying around idle.

 

http://www.mkivsupra.net/vbb/showthread.php?338202-Clutch-alignment-tool-for-V160

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Neither a local garage, nor Greg are likely to have the input shaft alignment tool for the twin plate clutch, just before someone pulls it apart and then thinks, oops ;)

Oh ok my mistake! Didnt realise you needed a specific tool to do those clutches my triple plate was all marked up when we did mine so it just went on the nose of the input shaft and bolted it back up to the basket/flywheel.

 

 

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Managed to adjust it as much as possible with more free play in pedal, I.e loads of thread on rod showing, and it's still slipping on boost. Bloody annoyed. Looks like it'll have to be removed and inspected fully to see what's going on.

 

 

 

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Oh ok my mistake! Didnt realise you needed a specific tool to do those clutches my triple plate was all marked up when we did mine so it just went on the nose of the input shaft and bolted it back up to the basket/flywheel.

 

 

Depends if the clutch has been converted from pull to push type and hence needs bolting to the flywheel BEFORE the g/box is offered up. Giken clutches are like that, hence you need the spline alignment tool. Once the clutch is off is a bit late to discover reassembling needs a spline alignment tool, so i thought forewarned and all that :) Bit like draining gearbox or diff oil BEFORE you check you can undo the filler plug :)

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In that case you probably DO NOT need a special tool for alignment. And a clutch that slips when there's no pre-load on the release bearing is usually FUBAR I'm afraid, or not rated for the TORQUE of the engine (HP is pretty much irrelevant, it's TORQUE....).

 

Looks that way Chris but I can't see how given I've not properly driven the car yet and clutch is rated to 800nm torque as per enclosed and I'm nowhere near that. Plus I've been running on low and medium boost to bed it on properly. Like I said it's never been right since install.

 

image

 

 

 

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My girlfriend 350z has just had a uprated clutch due to her OEM wearing out. A garage fitted the clutch but they said they was not happy with it so they disabled and re installed it again and I think replaced the slave, it was better but not right. They gave the car back to us as we needed it the next day and he told us see how you get on, any issues bring it back. Now like you he is far away so I tried I few things myself ..

 

When warm the clutch got harder and harder to get in gear, reverse was a nightmare. I had a feeling there was air in the system so I have bleed it a few times and now its spot on.

 

I know its a different car but might be worth a try mate

Edited by mplavery (see edit history)
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Looks that way Chris but I can't see how given I've not properly driven the car yet and clutch is rated to 800nm torque as per enclosed and I'm nowhere near that. Plus I've been running on low and medium boost to bed it on properly. Like I said it's never been right since install.

 

https://uploads.tapatalk-cdn.com/20170515/ac7fb9b10aaf69291829debcc8141b88.png

 

 

I honestly do think you have the same issue as me. Take it apart and reassemble it on a bench and if the plates dont slide into the basket smoothly thats the issue. Cant hurt to try i guess! Even better news about not needing the tool :)

 

 

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