Kennedy stage 2 fail

[jaqo]

Hello
I have a kennedy stage 2 p/p, it was installed on the flywheel few times but it was never run in a car. We put it in my fiat yesterday with Chris, pressed the clutch pedal few times but it didn't want to disengage completely no matter how did we adjust the cable. We decided to take the engine out and we did notice that some parts of the pressure plate where broken. I don't know if they where broken before or not. Does anyone know what could cause a problem like this? I have a diffrent pressure plate but I don't want to destroy it too. Could a too big throw out bearing movement cause this? That's just a guess, because we tried to tighten the cable a lot, but i don't see a technical possibility of it breaking those parts.

[Bruce]

What length is the clutch arm?

If you send it back to Kennedy, they will replace it.

[jaqo]

I'll check the length, (but remember it's in the fiat with modified fiat pedal assembly).
Why are you asking?

[Frallan]

Nope....I really do not think they will replace it.

Corrosion is a source of fatigue and could very well be the trigger point for breakage.
Not that I think so in this case as it is more likely with too long throw out bearing play.

[Bruce]

I'll check the length, (but remember it's in the fiat with modified fiat pedal assembly).
Why are you asking?

The length of the arm on the gearbox determines the travel of the TO bearing.  I know of 3 different stock lengths, the shortest gives the most travel.
You will also need to report on how long the lever arm at the pedal is.  This is equally important and may be the source.  What is the distance from the center of the clutch shaft to the cable?  (this assumes it's a similar mechanism to a VW)

[Bruce]

Nope....I really do not think they will replace it.

Corrosion is a source of fatigue and could very well be the trigger point for breakage.
Not that I think so in this case as it is more likely with too long throw out bearing play.

Kennedy is pretty good at replacing them.  I've known guys to send in clutches for resurfacing, and they got a new one back!

While it is true that corrosion can create stress risers that could be the location of a break, I would expect the parts to be designed with more safety factor than that.  The tiny bit of corrosion on his clutch shouldn't cause it to break.   I agree with your suspicion that it's TO bearing travel.

[jaqo]

Nope....I really do not think they will replace it.

It's not the point, any way it wouldn't be usefull - sending it from Poland to USA and back would cost to much

Corrosion is a source of fatigue and could very well be the trigger point for breakage.

Yes of course, but it's only a minor surface rust and dust - it's like a 2 years old or less, it was sitting in a garage.

Not that I think so in this case as it is more likely with too long throw out bearing play.

I thought about it but I can't see the way how a to long throw out bearing play would cause it to crack. I thought that maybe it can get stuck between the black part (housing) and the silver one (the plate itself) but I don't think so, after bolting it to the flywheel, there's still a lot of space and - as far as I can see - when you press the diaphragm spring with a throw out bearing, you just release the pressure that diaphragm is normally applying on this silver plate. It's NOT pulling this plate (like some other pressure plates I know) so I can't see the way a too long throw out bearing play can cause this. Am I missing something?

Bruce I do understand simple geometry like this;) I modified the pedal assembly so it would pull the same amount of cable as in a stock beetle (I had a beetle in a garage and just measured the cable movement;)) But i didn't know about the diffrent lengths of stock vw clutch arms, ooops Do you know what should be the value of this trow out bearing travel? I can measure it (taking the engine out takes like 5 minutes) I have a beetle gearbox there (of course). Meanwhile I'll measure all the dimensions.

Regards
Jan

P.S.
Frallan I started thinking about this engine swap and seriously planning it when I was like 15 years old because I saw your black beetle in Warsaw;)

[Bruce]

I thought about it but I can't see the way how a to long throw out bearing play would cause it to crack.

To understand this, you have to go way back in time to the early 70s.  In the olden days, the clutches had coil springs around them.  6 for the Type 1, 9 for the Type 2s.  That type of clutch is what the geometry of your car was designed for.
Now moving to today, nobody uses coil spring clutches any more.  We all use diaphragm spring clutches.  These new type clutches require a lot less travel to disengage them. 

  I modified the pedal assembly so it would pull the same amount of cable as in a stock beetle ....

That is good.  Next you need to measure the length of the arm at the rear (center of rotation to the center of the hole for the cable)
When VW switched to the diaphragm spring clutch around 73, they also made the clutch arm longer.  It went from 73mm to 90mm.  Then a couple of years later, they made it longer again, up to 100mm.  The longer arm at the gearbox causes less throw out bearing travel.

[nicolas]

also the KEP pressure plates are often already pressed in when you bolt them to the flywheel. they tend to be already engaged, if they are not shimmed out or the brake away pressure is measured, you could have had that problem. this does not relate to the clutch cable or pedal travel. the pedal only pushes the springs in and overstress them even more, which could lead to the breakage.

[Frallan]

P.S.
Frallan I started thinking about this engine swap and seriously planning it when I was like 15 years old because I saw your black beetle in Warsaw;)

Cool!!!

Like this? Memory lane.....
This is all  I have on my PC right now but I have more from Poland.  I am happy it inspired.

[jaqo]

I'm the guy (kid...) in a grey t-shirt with my head almost inside your car. You would be surprised how this place (and these people) looks like now;)  It was... 10? 8 years ago?
Sorry for the off topic.

Nicolas - how do you measure the breakaway torque? With the torque wrench attached to the clutch disk? What numbers should I aim for with stage 1 or stage2?

[Frallan]

I'm the guy (kid...) in a grey t-shirt with my head almost inside your car. You would be surprised how this place (and these people) looks like now;)  It was... 10? 8 years ago?

2004 or possibly 2005
I guess you are inside the car in this one?

[jaqo]

Nope - I think it's my brother (1914 cc bug owner now;))

[jaqo]

Ok - I put another pressure plate in, it didn't brake and it works.