Discussion
Tried to nip the pins up but it wasn't going to leave much clearance, so the only course of action was to push the pins out.
Fitted the pins properly and now I have this, which looks a country mile better. Looks more convincing with the hex seated up properly against the plate.
The pins have some damage, so have have tidied these up as carefully as I dare.
Just need the new star washers to appear, hopefully tomorrow.
Fitted the pins properly and now I have this, which looks a country mile better. Looks more convincing with the hex seated up properly against the plate.
The pins have some damage, so have have tidied these up as carefully as I dare.
Just need the new star washers to appear, hopefully tomorrow.
Star washers appeared and were duly fitted. I’ve now fitted up the clutch, got the bell housing in and bled the hydraulics.
Result: Not convincing....
Secondary plate now has clearance, but the primary plate at the flywheel does not get sufficient movement.
I’ll bleed the hydraulics again over the next day or so to see if that wins any further movement. From earlier work I’ve got the adjustment at the master to it’s max and if anything I’d rather be reducing that - still possible I suppose if there is some air trapped.
The pedal feel is decent, so I’m thinking that I’m being optimistic here. I suspect there is a slight moment of the pins at the star washers.
Worst case it’s a new clutch.
Does the club membership give discount at any of the bigger suppliers?
Cheers,
Brian
Result: Not convincing....
Secondary plate now has clearance, but the primary plate at the flywheel does not get sufficient movement.
I’ll bleed the hydraulics again over the next day or so to see if that wins any further movement. From earlier work I’ve got the adjustment at the master to it’s max and if anything I’d rather be reducing that - still possible I suppose if there is some air trapped.
The pedal feel is decent, so I’m thinking that I’m being optimistic here. I suspect there is a slight moment of the pins at the star washers.
Worst case it’s a new clutch.
Does the club membership give discount at any of the bigger suppliers?
Cheers,
Brian
Thanks both.
The springs look to be the originals, as I can see wear marks on the ones which contact the flywheel surface. The clutch worked prior to being 'reconditioned'. I did observe the two leaf springs are different guages between the primary and secondary plates. That seems to be in order.
I suppose if the leaf springs are weak, then the gap won't reliably be opened. The secondary plate has heavier guage springs than the primary one at the flywheel face, so I guess it's going to overpower those and allow the gap to open on the secondary plate first.
I've added another video to my excting YouTube series...This hopefully makes it easier to understand compared to my words.
https://www.youtube.com/watch?v=CMbfPwJz0l4
I played the video on my laptop and put a post-it on the screen so that I could mark the initial and final positions of the components.
The secondary plate has plenty clearance - Visually there's obvious movement,and the plate has clearance, but what's not so obvious is whether there's a little bit of loss of movement as the star washer stars/pins pull on the plate to open the gap for the primary friction plate.
I'm not so sure it's a compressibility issue of the linings, (so far). I was thinking if the lining was too compressible the secondary plate would get sqaushed, and then the star washers would be moved further down their pins, resulting in the secondary friction plate having no clearance when the clutch pedal is depressed? It would almost be like it's repositioned itself to account for wear.
My main question is whether there is enough movement (actuation) of the clutch unit? The company that rebuilt it made the commented that they adjusted the diaphragm spring angle when it went back second time to give it more movement.
If I understand this correctly, to operate without drag each plate needs between 0.5 and 1.0mm. So this would need 2 x clearance plus the difference between the star washer depth and the recess,
Things to do:
1) Bleed the hydraulics again to be sure
2) Measure the secondary friction plate clearance and compare to star washer thickness minus the recess depth
Sorry for the slightly chaotic post - my thoughts are processing as I go back and forth between the video's and various thoughts that you've kindly offered. At this stage it looks like I've fixed the problme of the pins (to some extent) but the weakness of the rebuild is that the leaf springs are the originals and show some signs of wear.
Beyond that I think a new AP clutch is on the cards. Might also seek a refund on the 'refurbishment'.
Thanks again,
Brian
The springs look to be the originals, as I can see wear marks on the ones which contact the flywheel surface. The clutch worked prior to being 'reconditioned'. I did observe the two leaf springs are different guages between the primary and secondary plates. That seems to be in order.
I suppose if the leaf springs are weak, then the gap won't reliably be opened. The secondary plate has heavier guage springs than the primary one at the flywheel face, so I guess it's going to overpower those and allow the gap to open on the secondary plate first.
I've added another video to my excting YouTube series...This hopefully makes it easier to understand compared to my words.
https://www.youtube.com/watch?v=CMbfPwJz0l4
I played the video on my laptop and put a post-it on the screen so that I could mark the initial and final positions of the components.
The secondary plate has plenty clearance - Visually there's obvious movement,and the plate has clearance, but what's not so obvious is whether there's a little bit of loss of movement as the star washer stars/pins pull on the plate to open the gap for the primary friction plate.
I'm not so sure it's a compressibility issue of the linings, (so far). I was thinking if the lining was too compressible the secondary plate would get sqaushed, and then the star washers would be moved further down their pins, resulting in the secondary friction plate having no clearance when the clutch pedal is depressed? It would almost be like it's repositioned itself to account for wear.
My main question is whether there is enough movement (actuation) of the clutch unit? The company that rebuilt it made the commented that they adjusted the diaphragm spring angle when it went back second time to give it more movement.
If I understand this correctly, to operate without drag each plate needs between 0.5 and 1.0mm. So this would need 2 x clearance plus the difference between the star washer depth and the recess,
Things to do:
1) Bleed the hydraulics again to be sure
2) Measure the secondary friction plate clearance and compare to star washer thickness minus the recess depth
Sorry for the slightly chaotic post - my thoughts are processing as I go back and forth between the video's and various thoughts that you've kindly offered. At this stage it looks like I've fixed the problme of the pins (to some extent) but the weakness of the rebuild is that the leaf springs are the originals and show some signs of wear.
Beyond that I think a new AP clutch is on the cards. Might also seek a refund on the 'refurbishment'.
Thanks again,
Brian
That's good to know the movement looks reasonable. Think I'll have to devise a photo and give the bits names.
I think I'll add to my list - hold the clutch down and see if I can persuade the plate nearest the flywheel to move. That might help identify it it's the leaf springs that are tired. Suspect this is ultimately looking like a replacement job, albeit I now understnad the whole thing better. I should really do a clean write-up of this to collate things a bit more.
Thanks Qbee for the info on the discounts. It essentially pays for a years subs.
I noticed that Powers market their clutch as uprated, seemingly to cope with their upgraded engines. Not sure I can justify their full price, and I also don't rag my standard car to within an inch of it's life. Hmmh. I usually heed the 'buy cheap buy twice' mantra, but have not done well in this case..
I think I'll add to my list - hold the clutch down and see if I can persuade the plate nearest the flywheel to move. That might help identify it it's the leaf springs that are tired. Suspect this is ultimately looking like a replacement job, albeit I now understnad the whole thing better. I should really do a clean write-up of this to collate things a bit more.
Thanks Qbee for the info on the discounts. It essentially pays for a years subs.
I noticed that Powers market their clutch as uprated, seemingly to cope with their upgraded engines. Not sure I can justify their full price, and I also don't rag my standard car to within an inch of it's life. Hmmh. I usually heed the 'buy cheap buy twice' mantra, but have not done well in this case..
The pin should be fixed as the star washer movement is controlled by the depth of the recess it sits in. This allows the star washer to move one direction on the pin and compensate for wear. Quite a neat and simple solution I think.
That aspect is probably now working correctly. It would appear the next issue are the leaf springs at the flywheel - these are possibly worn and weakened, hence not moving the driven plate off from the primary plate.
I’ll examine it more if this rain stops...
Cheers,
Brian
That aspect is probably now working correctly. It would appear the next issue are the leaf springs at the flywheel - these are possibly worn and weakened, hence not moving the driven plate off from the primary plate.
I’ll examine it more if this rain stops...
Cheers,
Brian
notaping said:
If you look as ukkid35's photo you'll notice that the intermediate plate has half of the springs cut away on the finger place side. This means there will be a bigger push away from the flywheel. I also had this on the first clutch I replaced. As a last resort it might be worth trying.
I was just studying this photo a bit more, and that has more spacers underneath the leaf spring at the flywheel side. Mine has none.Had another look at this at lunchtime.
I depressed the clutch pedal and jammed it down to allow me to examine the clearances. I reckon I’m seeing just over 1mm at the secondary friction plate and nowt at the primary one that mates to the engine flywheel.
If I carefully pry the driven plate beside the primary friction plate it moves reasonably well.
I think the start washers and pins are okay, but perhaps loosing me some movement, but possibly the overriding factor is that the leaf springs at the primary friction plate are not performing well.
Given that I’d rather be driving than spannering I think I’ll throw in the towel with this one and get a new AP unit. Might recover some cost by selling the refreshed friction plates I suppose..
Thanks to all for you input!!
I depressed the clutch pedal and jammed it down to allow me to examine the clearances. I reckon I’m seeing just over 1mm at the secondary friction plate and nowt at the primary one that mates to the engine flywheel.
If I carefully pry the driven plate beside the primary friction plate it moves reasonably well.
I think the start washers and pins are okay, but perhaps loosing me some movement, but possibly the overriding factor is that the leaf springs at the primary friction plate are not performing well.
Given that I’d rather be driving than spannering I think I’ll throw in the towel with this one and get a new AP unit. Might recover some cost by selling the refreshed friction plates I suppose..
Thanks to all for you input!!
The slides are new, and one of them was missed off when it first was rebuilt - that was corrected and I recall checking and it seemed a decent movement.
It was a bit crunchy going into reverse or first, but otherwise okay. I always put that down to either the box itself or clutch wear.
It was a bit crunchy going into reverse or first, but otherwise okay. I always put that down to either the box itself or clutch wear.
The optimistic bit in me says give it a go, but my experience on the initial build and the drag I got from the secondary plate with it's 0.3mm clearance makes me think I'd be on a hiding to nothing.
I went to buy a clutch yesterday only to discover they'd sold out and were awaitng new stock.
On a more psoitive note I bled the brakes last night. A bit heat and cold spray had all the bleed nipples out without any drama. on checking the front pads noticed they are green - EBC Green stuff I assume. These don't seem to be well recieved in Cerbera circles, and I can't say I've ever thought the brakes were good. In my mind they seemed to lack bite, which may of course be that these need a bit of heat through them.
Probably add something more appropriate to my shopping list..
I went to buy a clutch yesterday only to discover they'd sold out and were awaitng new stock.
On a more psoitive note I bled the brakes last night. A bit heat and cold spray had all the bleed nipples out without any drama. on checking the front pads noticed they are green - EBC Green stuff I assume. These don't seem to be well recieved in Cerbera circles, and I can't say I've ever thought the brakes were good. In my mind they seemed to lack bite, which may of course be that these need a bit of heat through them.
Probably add something more appropriate to my shopping list..
I think we are on the same wavelength.
I had someone at a party banging on about their personalised plate (amongst many other things) Had even been stopped by the police for it’s dodgy spelling of her name.
She was less than impressed when I pointed to my own car and suggested I could just change my name by deed pole to W663MAP and have a more accurate and cheap match. That halted the conversation.
I had someone at a party banging on about their personalised plate (amongst many other things) Had even been stopped by the police for it’s dodgy spelling of her name.
She was less than impressed when I pointed to my own car and suggested I could just change my name by deed pole to W663MAP and have a more accurate and cheap match. That halted the conversation.
My new clutch arrived today! Hopefully I'll get it built over the weekend.
In the meantime I'll take some measurements between old and new and see how the leaf/butterfly springs compare.
Hopefully I should be able to put together some form of guidance to prevent anyone else going through this rather torturous process.
In the meantime I'll take some measurements between old and new and see how the leaf/butterfly springs compare.
Hopefully I should be able to put together some form of guidance to prevent anyone else going through this rather torturous process.
Well, a good bit of spannering yesterday.
With just the bell housing on and hydraulics booked up we seem to have a functional clutch.
Spent the rest of yesterday putting it back together. Just got the exhaust to adjust before firing it up to see if it’s all good or not.
I took photos of old and new clutch units and a selection of measurements.
Also dropped the exhaust on my face whilst wrestling it into position. It’s heavy at the best of times, but more so resting on your face. Suffice to say my eyes watered today when I blew my nose!!
My general thought is the springs between flywheel and the driven plate are the cluprit. The new clutch seems to have a different spring and it’s spaced up.
Fingers crossed. New tyres to collect tomorrow.
With just the bell housing on and hydraulics booked up we seem to have a functional clutch.
Spent the rest of yesterday putting it back together. Just got the exhaust to adjust before firing it up to see if it’s all good or not.
I took photos of old and new clutch units and a selection of measurements.
Also dropped the exhaust on my face whilst wrestling it into position. It’s heavy at the best of times, but more so resting on your face. Suffice to say my eyes watered today when I blew my nose!!
My general thought is the springs between flywheel and the driven plate are the cluprit. The new clutch seems to have a different spring and it’s spaced up.
Fingers crossed. New tyres to collect tomorrow.
Fired it up and all gears engage nicely. Absolutely no crunch, so that’s good. It was still up on stands so I’ve still to get a feel for the bite point.
Sealed up the master cylinder cover which I think was my source of a rainwater leak, so an improve the.
Threw on the wheels with new tyres which look good. Can’t wait to take it a run!!
Sealed up the master cylinder cover which I think was my source of a rainwater leak, so an improve the.
Threw on the wheels with new tyres which look good. Can’t wait to take it a run!!
It's been a little while, but I managed to get an MOT and have put 800 odd miles onto the car.
I thought I'd update my experience with the clutch to perhaps help other decide whether to go down the refurbish route rather than buy an outright replacement. Hopefully it gives others a feel for the pro's and con's of clutch refurb versus replacement.
As a brief re-cap, I had to pull my engine out due to a shattered valve shim, which of course led onto having the heads completely refreshed, and then the bearings and rings replaced etc.. As I was that far committed, it seemed prudent to check the clutch linings and decide if these needed replaced. Looking at the history alone it seemed like they would need a refresh, and measuring their thickness confirmed that to be the case.
The dilemma was whether to refurbish the plates or replace the entire clutch unit. With the backdrop of significant outlay on the engine it's quite natural to look for efficiencies in other areas. I was always brought up on the basis that any fool can throw money at something. However, I also am mindful of buy cheap, buy twice.
I decided to try the refurbishment route. What I received back was a nice-looking unit. Everything looked decent. The plates looked good, the diaphragm spring looked fresh. All in all I was pretty pleased.
I duly fitted the clutch and got the big day of firing up the engine. Reverse and 5th were impossible to engage without much crunching. I bled the clutch a few more times. Having bought 5 litres of fluid to cover both the brakes and clutch I was horrified at the volume I have consumed on this affair!
However, despite this, no luck. It still was poor on 5th and reverse. So, out came the starter motor so that I could observe the clutch movement. At this stage it became obvious that the clearance for the plate furthest from the flywheel was insufficient. With hindsight this was because the pins with the star washers had not been correctly tightened by the remanufacturer. So, out came the gearbox.
The clutch was sent back to the remanufacturer, at their own cost for inspection.
On return the pins weren't tight, and I suspect there was a lack of understanding of how it actually worked. To resolve this I had to buy new star washers, split the clutch, tighten the pins and reassemble. This was gleaned for the good folk of this forum.
In went the clutch and gearbox, and the result was much the same. 5th and reverse, not happy. TVR owner also far from happy...
By this stage, I was fairly grumpy, and decided that a new clutch was the best course of action. This also gave me the opportunity to set the two units side by side and see what the issue could be.
The following photographs show the two units.
The upper is the refurb and the lower is the new AP unit. The profile of the spring is clearly different. You can also see the wear on the old spring
This view shows the units sat side by side on the ground - not the best photo, in terms of their respective height.
The new spring certainly looks to be at a better height than the old one. The gauges of the springs seemed to be the same. The primary spring - nearest the flywheel - was heavier than the secondary, on both units.
Similar photograph, perhaps better illustrates it.
Stepping back for a minute. The refurbishment process sorts out the friction lining and, I believe the diaphragm spring. The main problem is the 'leaf' springs that open the clutch at the primary and secondary plates. Those are not available as spares. As far as I understand AP will take the unit back and replace those, but the timescale is not too predictable. I suspect the desire is to supply a whole new unit.
The second issue that prevailed was flywheel wear. This corresponds to the wear on the springs noted above. When refitting the clutch, the key is to ensure that the springs are mated onto a 'fresh' part of the flywheel face. In my case I rotated the clutch round by one mounting hole. However, if the car has had a few clutches then the chances are that the flywheel is showing wear at either side of every clutch mounting hole.
Here's the wear either side of one hole.
Whilst that wear doesn't seem like much, when you couple that with tired/worn springs and a very small distance to open and close the clutch. it spells disaster. As I understand the clutch plate clearance is about 0.5-0.75mm. Tired springs and a worn flywheel are soon going to wick up that and give you a dragging friction plate.
cont....
I thought I'd update my experience with the clutch to perhaps help other decide whether to go down the refurbish route rather than buy an outright replacement. Hopefully it gives others a feel for the pro's and con's of clutch refurb versus replacement.
As a brief re-cap, I had to pull my engine out due to a shattered valve shim, which of course led onto having the heads completely refreshed, and then the bearings and rings replaced etc.. As I was that far committed, it seemed prudent to check the clutch linings and decide if these needed replaced. Looking at the history alone it seemed like they would need a refresh, and measuring their thickness confirmed that to be the case.
The dilemma was whether to refurbish the plates or replace the entire clutch unit. With the backdrop of significant outlay on the engine it's quite natural to look for efficiencies in other areas. I was always brought up on the basis that any fool can throw money at something. However, I also am mindful of buy cheap, buy twice.
I decided to try the refurbishment route. What I received back was a nice-looking unit. Everything looked decent. The plates looked good, the diaphragm spring looked fresh. All in all I was pretty pleased.
I duly fitted the clutch and got the big day of firing up the engine. Reverse and 5th were impossible to engage without much crunching. I bled the clutch a few more times. Having bought 5 litres of fluid to cover both the brakes and clutch I was horrified at the volume I have consumed on this affair!
However, despite this, no luck. It still was poor on 5th and reverse. So, out came the starter motor so that I could observe the clutch movement. At this stage it became obvious that the clearance for the plate furthest from the flywheel was insufficient. With hindsight this was because the pins with the star washers had not been correctly tightened by the remanufacturer. So, out came the gearbox.
The clutch was sent back to the remanufacturer, at their own cost for inspection.
On return the pins weren't tight, and I suspect there was a lack of understanding of how it actually worked. To resolve this I had to buy new star washers, split the clutch, tighten the pins and reassemble. This was gleaned for the good folk of this forum.
In went the clutch and gearbox, and the result was much the same. 5th and reverse, not happy. TVR owner also far from happy...
By this stage, I was fairly grumpy, and decided that a new clutch was the best course of action. This also gave me the opportunity to set the two units side by side and see what the issue could be.
The following photographs show the two units.
The upper is the refurb and the lower is the new AP unit. The profile of the spring is clearly different. You can also see the wear on the old spring
This view shows the units sat side by side on the ground - not the best photo, in terms of their respective height.
The new spring certainly looks to be at a better height than the old one. The gauges of the springs seemed to be the same. The primary spring - nearest the flywheel - was heavier than the secondary, on both units.
Similar photograph, perhaps better illustrates it.
Stepping back for a minute. The refurbishment process sorts out the friction lining and, I believe the diaphragm spring. The main problem is the 'leaf' springs that open the clutch at the primary and secondary plates. Those are not available as spares. As far as I understand AP will take the unit back and replace those, but the timescale is not too predictable. I suspect the desire is to supply a whole new unit.
The second issue that prevailed was flywheel wear. This corresponds to the wear on the springs noted above. When refitting the clutch, the key is to ensure that the springs are mated onto a 'fresh' part of the flywheel face. In my case I rotated the clutch round by one mounting hole. However, if the car has had a few clutches then the chances are that the flywheel is showing wear at either side of every clutch mounting hole.
Here's the wear either side of one hole.
Whilst that wear doesn't seem like much, when you couple that with tired/worn springs and a very small distance to open and close the clutch. it spells disaster. As I understand the clutch plate clearance is about 0.5-0.75mm. Tired springs and a worn flywheel are soon going to wick up that and give you a dragging friction plate.
cont....
In my case I have a new clutch mounted up on the best portion/orientation of the flywheel. If I'm lucky enough to be fitting the next clutch, then I'll be ordering a fresh flywheel for it, as it's likely going to be showing some wear.
At the end of the day the refurbishment route didn't work out for me. It's worked out for others, which is great. I'm hoping that the above helps fellow Cerbera owners gauge whether a refurb is a good route or not.
On the face of it, if you are doing your own spanner work, then £150+vat for re-ling the friction plates looks pretty good. If it's a known good clutch, then perhaps one refurb on a good flywheel is possible.
However, if you're paying someone else for their time to pull the gearbox and replace the clutch, then I'm not very sure the economics are all that good. Yes, it's a lower parts cost, but if the refurbishment doesn't work out, then the additional labour of removing the gearbox once more will wipe out any saving, plus you'll have the joy of buying a new clutch.
In this case I returned the clutch unit and received a full refund. It was still painful doing this work on my driveway, but on the plus side, I’m now pretty good at pulling the gearbox and clutch out.
Ultimately it seems a pity that for the sake of some pretty cheap springs the main clutch components have a relatively short lifespan.
Anyway, hopefully this is food for thought for anyone else contemplating a clutch and flywheel change.
Cheers,
Brian
At the end of the day the refurbishment route didn't work out for me. It's worked out for others, which is great. I'm hoping that the above helps fellow Cerbera owners gauge whether a refurb is a good route or not.
On the face of it, if you are doing your own spanner work, then £150+vat for re-ling the friction plates looks pretty good. If it's a known good clutch, then perhaps one refurb on a good flywheel is possible.
However, if you're paying someone else for their time to pull the gearbox and replace the clutch, then I'm not very sure the economics are all that good. Yes, it's a lower parts cost, but if the refurbishment doesn't work out, then the additional labour of removing the gearbox once more will wipe out any saving, plus you'll have the joy of buying a new clutch.
In this case I returned the clutch unit and received a full refund. It was still painful doing this work on my driveway, but on the plus side, I’m now pretty good at pulling the gearbox and clutch out.
Ultimately it seems a pity that for the sake of some pretty cheap springs the main clutch components have a relatively short lifespan.
Anyway, hopefully this is food for thought for anyone else contemplating a clutch and flywheel change.
Cheers,
Brian
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