Dead clutch and/or gearbox?

[bmcecosse]

My post was saying exactly that - if you fit a thick 1098 backplate then you need all the 1098 fly/clutch/release. But you could probably get away with a new thick carbon thrust bearing for a while - especially if you refit the return spring......and tighten up that loose screw on the restraining cable !

[Peatree]

Ok I understand why this might cure the problem, but I'd need a thrust bearing with about an inch or more of extra material for this to solve the problem, i.e take up all the slack seen in the photos. Does such a part exist? Surely this would be common knowledge on the forum if it were such a simple solution to matching a 1098 box to a 948 lump?!?

I suspect there may be more than this to the problem in any case... My experience of using the pedal is that of, say, the entire 6 inches of pedal travel, the clutch does not disengage until the very last half inch, hence changing gear with anything other than max pressure on the pedal to make sure it really is disengaged results in crunching. Then, if successful, releasing he clutch means it's engaged again almost instantly from lifting back off. An extra thick thrust bearing would seem to be a solution, but I could do with more than an inch of extra movement in the clutch and pedal to avoid it wearing again any time soon?

Apologies if this is tiresome, I have some understanding of mechanical principles and engineering but I am learning his as I go!

[bmcecosse]

You won't get an extra inch on the carbon thrust - is it possible the clutch fork (that holds the thrust) is bent with over pressure having been applied ? The REAL answer is all 1098 parts with the 1098 gearbox.

[Peatree]

You won't get an extra inch on the carbon thrust - is it possible the clutch fork (that holds the thrust) is bent with over pressure having been applied ? The REAL answer is all 1098 parts with the 1098 gearbox.

So not a thick thrust bearing after all then... ;)

I was thinking the arm must be bent with the abuse it's been getting - previous owner pleaded ignorance so I think the sensible thing all round is all correct 1098 parts and suck it up with some fresh new parts since the engine is coming out in any case.

[philthehill]

I very much doubt that the clutch release arm is bent. It is a piece of forged steel. If there was that much pressure the alloy flanges upon which it pivots and that hold it in place would break away.
When I fitted a 1098cc gearbox to my tuned 948cc engine whilst wanting to keep the lightened 948cc flywheel and comp clutch I had to re-align (bend by heating) the arm and take a small amount out of the carbon thrust top edge to get it to work but work it did.
I agree that fitting all 1098cc parts is the best solution - also the 1098cc ribbed gearbox is a better box than the 948cc smooth cased box.
Phil

[Peatree]

I very much doubt that the clutch release arm is bent. It is a piece of forged steel. If there was that much pressure the alloy flanges upon which it pivots and that hold it in place would break away.
When I fitted a 1098cc gearbox to my tuned 948cc engine whilst wanting to keep the lightened 948cc flywheel and comp clutch I had to re-align (bend by heating) the arm and take a small amount out of the carbon thrust top edge to get it to work but work it did.
I agree that fitting all 1098cc parts is the best solution - also the 1098cc ribbed gearbox is a better box than the 948cc smooth cased box.
Phil

Great to know, thanks Phil. Seems I have a plan.....thanks all. I'll report back on progress....

[bmcecosse]

Yes there are thicker/unworn thrust bearings - and with more 'offset' on the mounting lugs - just not an inch - although how/why you think you need an 'inch' is beyond me. I did say it could maybe keep you going for a while as a low cost fix. I think with some research you may get 1/4 to 3/8" inch more at the thrust - which translated through the leverage could lift the pedal significantly. Someone was recently trying to sell a bent clutch fork....so it can happen. You STILL don't explain where the return spring has gone. I'm going to duck out of this thread now as I'm not amused by the tone of the replies from the OP. We're only trying to help and it doesn't seem to be appreciated.

[Peatree]

Yes there are thicker/unworn thrust bearings - and with more 'offset' on the mounting lugs - just not an inch - although how/why you think you need an 'inch' is beyond me. I did say it could maybe keep you going for a while as a low cost fix. I think with some research you may get 1/4 to 3/8" inch more at the thrust - which translated through the leverage could lift the pedal significantly. Someone was recently trying to sell a bent clutch fork....so it can happen. You STILL don't explain where the return spring has gone. I'm going to duck out of this thread now as I'm not amused by the tone of the replies from the OP. We're only trying to help and it doesn't seem to be appreciated.

Ok... Er... Not sure I've been anything other than appreciative?! Coming back with additional photos and questions is nothing more than curiosity. I have zero intention to upset or annoy anyone so I'll say again... Thanks for the help ALL have offered. I believe I've shown this by confirming I'm taking the advice and acting on it. The debate over bent forks was not my reply, so I hope this isn't what you are referring to?!

FYI, the return spring was removed to adjust the arm, nothing more. I apologise if the lack of this clarity upsets you, but regardless, nothing in my description of the problem has anything to do with the pedal failing to return.

I'll come back again when I have an update, and have made use of the very friendly advice offered here. Id have thought as a user with over 40k posts you'd be experienced enough be able to look beyond forum posts as an indicator f true attitude and personality and not rush to judge someone asking technical questions.

Anyhow, came here for advice on a bloody Morris minor and not to fall out with a stranger so, in case you missed it, thanks for your help!

[bmcecosse]

It's the "so not the release bearing then " that bugged me - it IS the release bearing that could solve your problem - for a while. And that could be years if the car is just a week-end warrior. And the lack of return spring could be why the bearing has worn out quickly - but at long last you have agreed that it is just removed for clarity... I get that. Good luck with it all then...