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I would check and see is a previous owner did the clutch mod.. The only other things I can think of would be a missing fork pivot point but that would be very obvious or if the pressure plate was not fully seated against the flywheel. Can you grab a picture of your clutch pedal, this honestly sounds exactly like the problem I had with mine.
 

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Discussion Starter · #22 ·
I guess I can't rule anything out but I've had the car since 15k miles and it's highly unlikely it was tinkered with but let me know if anything here looks different!

1280487

1280488
 

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Nothing back there to stop clutch travel that I see?

The clutch gets cockeyed on the shaft by a few degrees and the binding won't let it slide. One thing about this though is that the pedal effort did feel slightly higher and there was no "fall off"
 

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Nothing back there to stop clutch travel that I see?

The clutch gets cockeyed on the shaft by a few degrees and the binding won't let it slide. One thing about this though is that the pedal effort did feel slightly higher and there was no "fall off"
Kevin,
That was one of the questions I asked and he said that it did feel the clutch point in the pedal.
Later,
Eldon
 

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Discussion Starter · #25 ·
I maybe had a bit of progress this morning. I wanted to get the car up to temp to bleed coolant and check everything over. Once done I turned the car off, and tried starting it again in 5th with the clutch depressed. It stalled, repeated it a couple of times and after a bit of clanging and clattering I can now start the car in 1st or 2nd (with clutch in) and it doesn't stall, rear axles don't spin but there is a smell of clutch floating around the garage which suggests it's at least partially engaged still.

I'll get the car on its wheels later today and will try a few manoeuvres around the street (hopefully none that cause me to lurch into a lampost!) and see if it frees off a little more, but based on the burning clutch smell I think maybe the longer pushrod might be my saviour.
 

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I maybe had a bit of progress this morning. I wanted to get the car up to temp to bleed coolant and check everything over. Once done I turned the car off, and tried starting it again in 5th with the clutch depressed. It stalled, repeated it a couple of times and after a bit of clanging and clattering I can now start the car in 1st or 2nd (with clutch in) and it doesn't stall, rear axles don't spin but there is a smell of clutch floating around the garage which suggests it's at least partially engaged still.

I'll get the car on its wheels later today and will try a few manoeuvres around the street (hopefully none that cause me to lurch into a lampost!) and see if it frees off a little more, but based on the burning clutch smell I think maybe the longer pushrod might be my saviour.
Longer push rod wont do anything. You can draw the hydraulic system and convince your self easily
 

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Discussion Starter · #27 ·
Longer push rod wont do anything. You can draw the hydraulic system and convince your self easily
Honestly I've read so many posts on it and I fully agree with that, I can't imagine how it works based on how the hydraulic system works... but there are just so many good reviews out there from people who have fitted them and it's "transformed" their shift for the better.

I've just hacked up an 8mm allen key to allow me to prove the concept for myself. At this stage, it's worth a try.
 

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It will move the clutch point higher on the pedal. If everything was perfect, changing to a stiffer diaphragm would not change the clutch point but only create a stiffer pedal. The problem is that everything is not perfect. The system changes from hard lines to a flex line back to a hard line. The flex line will expand as pressure is built in the system. How much, depends on the style of line and it's age. When the flex line expands, the throwout bearing stops moving as much. By putting in a longer pushrod, you move the slave cylinder's idle position deeper into the cylinder housing. This works as long as you do not bottom out the slave cylinder and keep pressure on the throw out bearing.

Later,
Eldon
 

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Discussion Starter · #29 ·
Thanks Eldon, my cut down allen key is the same length as the extended pushrods that are on the market (1/4" longer) and based on my tests last night it shouldn't be in danger of bottoming out the cylinder.

I went back down to the car earlier after it cooled down and I can now shift fairly comfortably into all of the forward gears, maybe with the slight hint of crunch if I did it too quickly. I still however cannot get reverse, it just grinds and I don't want to be too aggressive with it so have not forced it.

Adding the allen key is a cheap experiment, so I'll give it a try in an hour or two. If it lets me grab reverse, then with some confidence I can place an order with a proper one even if I have to pay/wait for one to come from the US.
 

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It sounds like you are still dragging the clutch disk. The forward gears have syncros which will allow you to shift into them. Reverse does not have a syncro so any motion in the shafts will cause a problem.
When you put the long pushrod in make sure that you have some play in the throwout bearing fork so that the bearing is not riding on the diaphragm. If it does, it will wear out the bearing really fast.

Later,
Eldon
 

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Discussion Starter · #31 ·
When you say play, do you mean in the fork itself or in the pedal?

I'll check before making any changes but I'm pretty sure that my fork has no free play anyway, the resistance of the fluid and the spring inside the slave seems to keep the clutch fork pretty tight and even with the standard length pushrod I have to push pretty hard against the clutch fork to get the slave lined up to its bolt holes.

Is that not right? As far as I can tell, the car has always been that way.
 

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If I remember correctly, there should be a spring in the slave unit that pushes out the cylinder which is why it is a pain to install the slave unit. Those of us that do this frequently will install studs because it makes it easier to install the slave unit. By free play, you should be able push the fork back into the slave unit before it engages against the clutch diaphragm.

Later,
Eldon
 

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Discussion Starter · #33 ·
Thanks Eldonz, that makes sense. I did the studs already because it was a massive pain to push it on and line up with the SC bracket etc!

I did a couple more tests with my allen key pushrod. I did manage to crunch it into reverse, but it's not a nice sounding experience. My front suspension is also complete now, so my next trial is to get the car onto its wheels and wheeled out into daylight, I'll try driving a little bit to see how it feels whilst everything is loaded up properly but if it still feels awkward, I'm really running out of things to try other than dropping the box and considering a different clutch kit :(
 

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Out of curiosity, when you were tightening the clutch diaphragm bolts, did you turn each one a turn or two then go to the next one? Slowing working the diaphragm down to the flywheel.
Later,
Eldon
 

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Discussion Starter · #35 ·
Out of curiosity, when you were tightening the clutch diaphragm bolts, did you turn each one a turn or two then go to the next one? Slowing working the diaphragm down to the flywheel.
Later,
Eldon
That is my last remaining thought for an installation error on my part. I did tighten them down gradually, in a star pattern etc but then I second guessed my clutch alignment, slackened off slightly and re-did it. I may have caused it to slightly distort whilst doing that, I can't be 100%. It felt fine at the time, but all these little things are now running through my mind.

Anyway, it's definitely not right. Sometimes disengaging, sometimes not. Had the car on the road and it's very hard to get it into any gear from a standstill with the engine running, reverse still grinds and instantly starts moving me backwards with clutch fully depressed. Feck it, box out again.

Question is, should I be putting a brand new clutch in? Could I have damaged this one with my troubleshooting so far? Obviously it's money I'd rather not throw away as the current one has 0 miles on it... I guess I'll take it apart first and judge it's condition.
 

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It's hard to say. From your description, the diaphragm is definitely not completely disengaging. If the disk was pinched during installation, once the motor was spinning and the clutch depressed, the disk should have recenter itself. It really sounds like the diaphragm is not sitting correctly on the flywheel thus the fingers are not doing what they are suppose to be doing.

Good luck,
Eldon
 

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Discussion Starter · #37 ·
Thanks Eldon, your support has been much appreciate.

I'm sure I'll be back with news at the weekend...
 

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Discussion Starter · #38 ·
Sorry... me again.

I had a flash of motivation tonight, decided if I wanted to fix it this weekend then I had to get the clutch out tonight to give me chance to buy another one if it was trashed.



On first glance all was looking well, no bits of clutch hanging in the bottom of the bellhousing and no missing pressure plate bolts etc. There was a small scuff on the face of the splined hub where it looks like it maybe took a glancing blow by the input shaft on the way in, but it pretty much wiped off with my finger, no damage to speak of.



I took the pressure plate off, I decided (not sure why) to undo the bolts sequentially, sort of "following the clock", I loosened 3 off, then removed three, then did the same with the final 3. As I got round to the 4th bolt (I think) there was a loud twang as some tension was released and one of the bolts that was loosely in had a snapped washer that had splayed open. I've got no idea if this is expected behaviour undoing the pressure plate like this, it clearly had some pent up tension in there.... but that's the point isn't it?



There are some slight burn marks on the friction disc, pressure plate and flywheel - I imagine effect rather than cause of me trying to start the car in fifth and other such shenanigans. Is this detrimental? Obviously it's not ideal, but I'm hoping the product can stand up to it and it not make an appreciable dent in the lifespan of it.







I've taken some reference measurements from my OE clutch and everything seems to be within 1mm of each other, certainly within thresholds of wear. Wondering if I've ended up with a 1ZZ flywheel (for example) that might be just subtly different enough in its offset from the crank to cause issues, but really CLUTCH'ing at straws at this point.

I've got new pressure plate bolts coming on Saturday, so have 24 hours to investigate and try to find a smoking gun. I think the pressure plate bolt washer and the 'twang' I heard is about as close at I've got at the minute, but I'm not overly confident. As ever I appreciate input.
 

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It looks like the clutch is wearing only around the outside.. This might mean that something is not flat, did you replace the flywheel with the clutch or was the flywheel the same one used with your previous clutch?

I doubt its a 1ZZ flywheel as I believe that the bolt pattern and bore size are different and wouldn't fit the 2zz crank.

I would inspect the flywheel, clutch disk and pressure plate to see if there is any taper from the inner surfaces to the outer surfaces. It might also be possible that the washer bound up on the one bolt and the pressure plate wasn't fully seated in that area. Did you check to make sure the pressure plate was fully seated to the flywheel at each bolt location before you removed it?

From the looks of the wear around the bolt holes of the pressure plate and the location of the hot spots my best guess is that one of the points of the pressure plate wasn't fully seated against the flywheel warping the pressure plate carrier and applying uneven force on the clutch.

The bottom right bolt hole on the flywheel doesn't look like it has any ware marks from the clutch being torqued down against it like the other holes have. Similar to the clutch pressure plate image bottom left hole.
 

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Discussion Starter · #40 ·
I think you're right about the wear pattern, it does seem to be towards the outside.

I think the bolt hole witness marks are just bad photography, I've inspected them all and they're much the same. The washers have actually chewed into the pressure plate material a little bit which surprised me with such a low torque spec.

I think the washer binding and so not applying the true torque is the leading theory. I did rotate the full assembly from the side and checked that all contact points between PP and flywheel were flush which they appeared to be, but having the torque marginally off may not be obvious to the eye I guess.

I've done some basic checks with a flat edge and a light on the pressure plate to see if there's a taper, it doesn't seem so. I'll repeat the same test on the flywheel tomorrow once it's on the bench.
 
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