What on earth is wrong with my clutch???
 

Hi guys,

my clutch stopped working on my last track day, and I've been at a loss as to what's wrong with it. Here's the story.

Car was running well, nice and quick. About 10 laps in, I missed third and grabbed first gear instead. The car lurches but holds ok. A couple of laps later I actually get quick enough to get 5th, but when changing back down it won't go in gear. I finally get 3rd, but after that it won't select any gears at all.

I get recovered back to the pits and find that when stationary with the engine running I can't select any gears, but the car will edge forwards when trying to push the gearstick into a gear.

So I diagnose a clutch that won't release. After scouring BMW E34 websites, the suggestion is that the hydraulics are at fault. But after replacing the master AND slave cylinders and bleeding the system with a pressure bleeder, the problem is exactly as it was before.

So:

1. Clutch pedal feels fine
2. Car creeps (quite strongly) when I try and select a gear
3. It has a dual mass flywheel
4. Gears all select fine with engine off, and the car lurches if I turn the starter with it in gear, no matter if the pedal is up or down.
5. It's a BMW M60 3.0L V8 engine and gearbox from the donor E34 530i

I'm wondering now, has the clutch assembly separated from the flywheel? Has the dual mass flywheel broken somehow? (I have no experience with this type of flywheel)

I now have to pull the engine out and I have to get it fixed within 2 weeks for the CKC magazine track day. AAAAAaarrrggghhh! Help!!!

sounds like you gave the old girl a bit too much stick :rolleyes:
looks like its going to be a box off and take a looky inside somthing could be jaming the plate to the flywheel or somthing like that

ok should also have mentioned there are no untoward noises with the engine running, but, with the car in gear, if i rock it back and forth, there is an audible clunk from the bellhousing.

Thanks Baz, problem is, with engine and box separated, the clutch would be stuck on anyway. I'd be devastated to strip it down, not find anything obvious wrong wrong, reassemble it and find it to be still not fixed.

Could the clutch release bearing have collapsed or the bearing in centre of the dual mass flywheel causing you not to be able to disengage the clutch?

I would have a quess at the release bearing as the the flywheel tends to make noises before they really break.

It sounds very similar to my dual mass flywheel on my transit, the centre bearing had disintergrated and jam it in gear.

Terry

My guess would be a fractured cover disc that will then have bitten into the pressure plate had it on a triumph herald once everything just locks up and whatever it is I reckon it is a engine out jobby
good luck tho
K4

Lots of good theories here guys, I'm gonna start stripping it down tomorrow afternoon (as long as 'er indoors will let me).

Unfortunately the cheapest new clutch I can find is £277 !!! Eek!

http://www.ebay.co.uk/itm/New-Clutch...-/290471342805

Is it a 530 e34? This might do.

bob

Oh top find Bob! I'll get it apart asap and probably order one from there. Nice one!

Intresting problem. I am not familar with the set up on the BMW motor. But once had similar issues with a Ford CVH powered Scimitar. Turned out to be the pinion bearing collapsed. Could account for the clunk in the bell housing when you rock it

Part of the drive hub has possibly detached after a few hard take off's,the springs in the center sometimes come out.

Umm, dull question time....

What's the pinion bearing?

its a bearing for a pinion silly :rolleyes:

Ok, got the engine out this afternoon (what else are bank holidays for?) and although I haven't removed the clutch from the flywheel yet, it looks like whats happened is sudden and complete failure of the friction plate. There are bits of disintegrated friction material in the bellhousing, and chunks of it sticking out of the side of the clutch assembly.

I've got a new clutch ordered which will be here on Thursday.

Well, finally cracked it.

Pulled the clutch off today, and found that one side of the friction plate had lost all of it's friction material, which was piled up in the bellhousing and on the floor.

New clutch was due today, just found out I won't get it till Monday, great. In the meantime, there's lots of pics on my blog.

I reckon that its lost all of its newness:rolleyes: Might pay to upgrade to a hd unit

Bob

Heat has broken down the binder and the fibre element has been spun out into the bellhousing. I am dealing with at least 2 a month of these, quite often with people towing boats down to Cornwall and then launching the thing and cooking the clutch in the process.

I suppose the gander of a trackday could have the same results. A HD clutch has less friction material so is more likely to fry, not less.

I hope it was the cover plate side (it looks like it) - otherwise you'd be looking at a flywheel skim... :(

Sod it does that mean the hd competition clutch kit i bought that can handle 70% more torque is not as good as the standard unit???????????

Bob

No it was the flywheel side, it's nice and smooth though, no heat discolouration damage evident.

It will handle more torque, but for much less time

All fixed! and just in time for tomorrows track day at Llandow. It will be great fun bedding it in on track :rolleyes: