Cluch springs fouling levers.

[luvvaminor]

Back after a forced absence. I have searched the topics because this must have happened before, but it is a complex description; best if you look at the attached photos and tell me why this has happened. The driven plate springs and the tabs that hold them have been rubbing on the actuating levers (I hope my terminology is near enough). The clutch was fierce and high when I got the car, I assumed it needed a new clutch and I have ordered one but the old one although worn is not down to the rivets. Can anyone enlighten me please? I can get a photo of the release bearing but it has plenty of life in it.
Colin

[philthehill]

The clutch levers are over centering. Over centering should not happen if the clutch is adjusted correctly and the right thrust bearing is fitted.
I would advise that the pressure plate is replaced as well as the driven plate and thrust bearing.

A photo of the rear face of the pressure plate thrust pad would be helpful.

[luvvaminor]

Thanks for replying. I attach a photo of the thrust plate. I have had the car for some years and I did drive it for a while and I tried to adjust the clutch but it was critical. I've now got around to the job. I will be getting the complete B&B kit (which I notice some people are not impressed with) so probably on Monday I will be able to compare. Can't really look at the thrust bearing now, but it looked ok.

[luvvaminor]

Well, I dunno . I attach comparison photos of my new and existing driven plates. Rather different - the boss depth of the one that was fitted is 28mm, the new one from a well-known trusted supplier is just under 19mm. There were many bodges that I discovered on this car, can it be that completely the wrong driven plate was fitted? Incidentally, the new plate is very lightweight compared to the old, and barely 7 1/8th" diameter against nearly 7 1/4". I know it is the metal discs that measure a full 7 1/4", so presumably this is immaterial. But surely the difference in overall thickness must be significant? The clutch was impossible to adjust correctly.

[philthehill]

You do need to prove what the original problem is/was otherwise it may be carried over to the new clutch assy which may not then last very long.

I would suggest that you remove the flywheel, place it on the bench and fit the old cover and new centre/driven plate.
Tighten it all up and see what the position/clearance of the 3 old cover fingers.

The fingers should be well clear of the scuffed shock absorbing springs. A photo of the assembled clutch assy with the rubbing plate removed would be appreciated..

The fingers only have to be depressed a small amount to release the clutch.

If you have access to a press you can depress the fingers as if you are releasing the clutch and see what the clearance is and what position the fingers are in when you can move the centre/driven plate.

If the fingers have been played around with and the clutch linkage is set incorrectly the fingers will over-centre and the result will be scuffed shock absorbing springs.

See the BMC wksp man section E & EE for setting up details.

The new centre plate does look to be a light weight item compared to the original centre plate but if of a reputable make there should be no problem.

The new centre plate does not have the splined boss forward of the friction plate which will reduce the overall depth of the clutch but should have no detrimental effect on the clutch operation.

[luvvaminor]

It's not just the boss that is longer. The distance from the clutch face to the protruding springs is only 7mm on the new disc, on the old disc it is 11mm. I wondered if that was enough to cause the clash. I looked up the number 47238 stamped on the old clutch. It wasn't conclusive but it seemed to point to clutches fitted to 1500cc engines. I was going to do measurements in the manner you suggest but the engine is in the car and I'm not going to do any more dismantling unless forced to. I am old and I ache. I was going to use an accessible flat surface and simulate the flywheel position.

[philthehill]

Can you please give a pointer as to what 1500cc engine/car.

[luvvaminor]

I was led to references to Triumph Sptifires. Getting to the actual sites, the specific number was not used but it must have been linked somehow.

[luvvaminor]

Here is one clear reference linking the Triumph to that number.

[philthehill]

Examining the MOSS parts list the clutch driven plate (10 spline) is for a non UK/Europe Triumph Spitfire 1500cc (Pt No: GCP103AF) which is the same as the Morris 1000 1098cc driven plate (Pt No: GCP103AF).
The UK and Europe Triumph Spitfire 1500cc has a 20 spline driven plate Pt No: GCP230.

To reiterate:-
The original clutch cover or clutch release linkage has been set wrong so as to over centre and/or give excessive travel to the pressure plate fingers.

[luvvaminor]

Ok. Whatever, the plate is different, I have a whole new assembly, everything else looks ok and I think I'll put it all back together and it will be fine. There aren't many sunny days left...

[philthehill]

"It will be fine" is a good attitude but you will still need to determine what was the original cause of the problem so as not to have the same problem arise again further down the road.
I would check that the clutch operating linkage is correctly assembled and that you have 3/4" free play at the pedal.

[luvvaminor]

I am making the assumption that the new clutch assembly is set up to a standard, whereas the pivot settings on the old one may have been "got at". Obviously I will be careful with the pedal linkage setup and I will make sure that there is minimum clutch releasing movement together with full disengagement. I think if I had waited until I received the new clutch I wouldn't have taken up valuable forum space with my photos and query! Over 100 views and only you replied, thanks!

[philthehill]

The forum is doing for you exactly what is was designed for - interaction and problem solving for both MMOC and non MMOC members.
Just happy to be of help.
Phil

[luvvaminor]

Well, I have put it all together, including many other jobs and there are still a few remaining before hitting the road (I hope not literally). The clutch is now fine. I have a rather complicated theory about what may have happened with the original fierce clutch which I will outline as a possibility. I think if I had made the gouges in the clutch mechanism I would have heard something and I believe the adjustment was not at fault. I know the previous temporary owner was a bit of a bodger. Suppose he over-adjusted the release and heard those noises. Suppose he hurredly disassembled and actually turned the pressure plate around the wrong way, assuming that this was the problem because of the marks on the springs. Would this explain the on/off nature of the clutch that I inherited, due to the shock-absorbing springs not functioning? When I took the clutch off the plate fell out so I cannot say it was definitely backwards, but it is the only explanation I can think of. As I said in my previous post, the linings and release bearing were fine. I renewed the bearing for the new clutch obviously. Pointless speculation I know, but it was puzzling. I like to know the "why" of things.