Clutch issues

Post by **foggyjames** » 22 Sep 2007 04:02 am

Well my trip to Santa Pod has been called off thanks to clutch problems. I'd like some ideas on what could be causing it, before I invest a lot more time in sorting it out. I've just popped a new clutch in the 360. The old one was slipping, so while the box was off, it made sense...

I got a 3-piece clutch kit from Carl. All pieces were a visual match, and it was a Borg & Beck unit. On refitting, the clutch dragged (i.e. didn't disengage), making gear selection impossible with the engine running. I tightened the cable to achieve more 'peak' compression of the clutch, and it improved matters, but the clutch now slips - presumably because the clutch is constantly semi-released.

My S70's clutch failed in exactly the same way (i.e. it dragged). I have no idea what actually solved the problem, but a new 3-piece kit was fitted, and it fixed it. Which piece was faulty was unclear...but either one of the 3 pieces, or the act of re-seating the box (unlikely) solved the problem.

Any ideas on what could be causing this? Everything looks AOK. The fork appears to be correctly aligned - short of a faulty clutch, an incorrectly seated fork is the next favourite, in my book....but seemingly not so in this case. I guess all I can do is take it all apart again and check it as I go. At least a dragging clutch can be tested with the car in pieces, whereas a slipping clutch must be tested 'on load', with the car fully assembled.

cheers

James

Post by **classicswede** » 22 Sep 2007 11:29 am

If it is a new borg & beck then it could actualy be a LUK clutch wich are a pile of shite.

Asuming that the problem you have is not the reason why you changed the clutch I would guess its a pressure plate problem.

Also to ask the idiot question are you sure the friction plate was fitted the correct way around?

Post by **foggyjames** » 22 Sep 2007 12:51 pm

I'm 99% certain I fitted it correctly, but it's a bit late to check now

The clutch wasn't dragging before I fitted the new one.

One theory I'm working on - what if the pilot bearing were damaged or the TT shaft mis-aligned in the pilot bearing? That would transmit some drive to the shaft regardless of clutch position.

cheers

James

Post by **V6 Man** » 22 Sep 2007 02:05 pm

In theory the input shaft should be a snug fit in the pilot bearing so unless the bearing were damaged there should be no issues there with misalignment - if the bellhousing is flush with the block then the input shaft is in the PB.

If there were no dragging issues before the swap the the PB was ok, so unless you managed to shatter/seize it when refitting the input shaft then it still should be ok.

Did you refit a new thrust bearing or reuse the old one?

Post by **foggyjames** » 22 Sep 2007 02:16 pm

It was a bit tight getting the shaft into the pilot bearing...but it always it. Yes, I used a new release bearing.

Hmm...'tis curious, this...

cheers

James

Post by **redline** » 22 Sep 2007 02:24 pm

I was going to say friction plate wrong way round ,

the centre bore can be offset more on one side than the other if that makes sense

pressure plate side

fly wheel side

perhaps a new cable might be wotrh investing in as well

Post by **foggyjames** » 22 Sep 2007 02:47 pm

Aye, I'll put a new cable in when I put the turbo motor in.

I doubt the plate would bolt up flush with the flywheel with the disc the wrong way around. It certainly is offset (quite a bit) on a 'dished' flywheel car.

cheers

James

Post by **pettaw** » 24 Sep 2007 07:39 pm

I've got 3 suggestions. One is that the friction plate is in backwards. An other is that the release fork has become displaced from the pin inside the bellhousing. The third is that the clutch has seized onto the input shaft and won't come free.

Unfortunately fixing any of the three involve taking off the clutch housing again and all the pita that causes.

Post by **foggyjames** » 24 Sep 2007 08:32 pm

I'm not sure the disc will physically fit backwards...otherwise I agree that it is a favourite. I think the fork is a distinct possibility, although it looks & feels ok...usually it's pretty obvious when it's off, although I'm speaking about hydro clutches which typically have a centre pivot, so it may be different with an end-pivotted cable clutch.

Yes indeed...theorising is all well and good, but I need to get my hands dirty. Dammit. I've had enough for a week or two, but I'll get back on the wagon once the house it tidier and we've sorted some of the issues with it out. The car has had it's time for the moment

cheers

James

Post by **Carl** » 24 Sep 2007 10:07 pm

Doh sorry to hear of your troubles

IIRC I got it from someone on the VOC forum that I had used before without issues.

How does the clutch pedal feel compared to before? Lighter, heavier? Did you grease up the input shaft when putting it all together?

Sounds like s similar problem to what Nat recently had on the 205, which I knew was a release bearing (common problem in old clucthes on them). I resorted to taking the bellhousing bottom cover off, getting a can of white grease with the straw attachment thingy and poking round the flywheel and squirting the input shaft/bearing (and the inside of the casing!) with grease. Worked a treat for a couple of weeks until I found time to change the clutch.

Post by **foggyjames** » 25 Sep 2007 12:11 am

On the face of it, I doubt the clutch is defective. Even if it is, don't you go worrying about it!

The pedal felt similar with a 'normal' amount of preload on the cable. It's damn stiff now, but it would be

I didn't grease the input shaft. I've never done that before, and the manual for the S70 (the last clutch I did) specifically said not to do that, so I was still in that 'mode'. I guess it's possible that if the plate isn't sliding when it's released, the tiny bit of drag created could cause a problem.

I'm still favouring something *like* the fork not being attached properly.

cheers

James

Post by **huskyracer** » 25 Sep 2007 08:30 pm

I recon youve hit the nail on the head with your last post there Foggy, thats what makes it "tight " putting the housing back up too. Seen this a few times, usualy its because there is loads of paint in the splines, Always remember to check the plate fits the imput shaft BEFORE you are trying to wrestle big bits of transmission onto it in the car.......

Post by **foggyjames** » 26 Sep 2007 12:36 am

Thanks Iain. I'll try to work out what's wrong when I take it all out. I was going to call you tonight, actually...but ended up having to go shopping. I'll give you a bell another night.

cheers

James