Clutch Budgie Squeak!

[Pete Lewis]

you can drill a new pin position to wear in a new place ...easy 

we have replaced the fork pins in the past with cut down clevis pins 

having the correct brg is a plus  ,  these wear patches all alter the angle the throwout arm works at and yes there is lost leverage 

but wont make the chatter we can see   .but will give heavier pedal loads 

the wear is pretty normal after all these years but fixable  

Pete

 

[Iain T]

Seems a fair amount of pin wear. The problem with most clevis pins is they are as soft as doughnuts so in my view OK for extreme wear cases but you are on a mission to get it ready for the RBRR. 

Fit a split pin in a different position on the carrier as Pete says, I did. Use the correct dowel bolt to align the bellhousing and see if it's any better. I used a normal bolt as it measured pretty much spot on but don't use fully threaded set bolt. 

If its still noisy try singing when stationary 🎶 and have fun next week. Post us how you're getting on please. 

Iain 

[Pete Lewis]

here is a few clues about what happens from a problem misalignment is on one of them  Ha !!

Pete

clutch 3.pdf clutch diag 1.pdf clutch diag 2.pdf clutch failures 4.pdf

[Phil C]

Thanks both. 

Pete, they didn't help! It's like when you look up the cause of an ache or pain on the internet - it always concludes you are going to die!!! 

I think Iain is right. Given the time pressures I will reassemble with the 3/8 dowel bolt and taking care everything is as it should be. Hopefully that will sort the noise/jiggling, but if not, at least get me around the RBRR and to be sorted later!!

With regard to pinning the carrier, not something I have done before. Advice as to how to do this to ensure the pin doesn't fall out would be welcome. Thanks.

Edited October 1, 2023 by Phil C

[Iain T]

3 minutes ago, Phil C said:

With regard to pinning the carrier, not something I have done before. Advice as to how to do this to ensure the pin doesn't fall out would be welcome.

I used a 3mm diameter split pin. Drill holes through the both sides of the grove and push in the pin. The split pin acts as a stop against the fork pins and prevents the carrier from rotating. I think Paddocks and Rimmer sell the carriers with the pin already fitted but then you'll have to remove your bearing and refit. 

Iain 

[johny]

I would like to do something about the fork pins as that amount of wear allows it to rattle around more in the carrier slot. Can they be rotated? Whatever is done has to be good so maybe a spot of weld? You dont want them coming loose later😲

[Pete Lewis]

if you use a spit pin just open the legsthen  it cant fall out    early cars had a small spiral  roll pin , 

and the misalignment due to wrong sized  dowel bolt would make the concentrity between clutch cover and throw out bearing very dubious  and can end up with the clutch disc hub fracturing .

certainly it wont help  but easy to fix  , just find the 3/8" hole  its there ...somewhere 

Pete

 

[Phil C]

3 hours ago, Iain T said:

I used a 3mm diameter split pin. Drill holes through the both sides of the grove and push in the pin.

Will the split pin not restrict the carrier movement towards the gearbox?

[johny]

Remember the bearing is always held in contact with the clutch cover and then moves forwards so well clear of gearbox...

[Ian Foster]

19 hours ago, johny said:

Now I look in the manual under torque settings it does say 5/16" stud, 5/16" bolt and 3/8" dowel bolt for the gearbox to backplate fixing...

I likewise had never spotted this before.

The WSM text doesn't seem to make any reference to a dowel, although page 2.108 has a photo of the engine backplate from the clutch side and there is clearly a stud at the top. (as attached)

You've got me wondering now. I'm pulling the gearbox for a clutch change from an overly strong modern Borg and Beck to a Sachs unit, so will pay due attention on reassembly.

Phil, I don't suppose you put a dial gauge on the diaphragm fingers to check for run-out. That's the only thing I can think of that would wobble the release bearing! BTW I do have a serviceable Classics Clutches (B&B type) and a new 10 spline plate available FOC if you are need. (I'm in Wareham, Dorset).

Ian

PS I have just found a photo of the back of my engine with the top dowel in place. Mildly relieved!

Scan_0120.pdf

Edited September 28, 2023 by Ian Foster
update

[johny]

It wasnt the dowel that was the surprise but the oversize dowel bolt used in one of the positions (5 oclock?) to bolt the gearbox on and act as a second positive location point for it....

[Phil C]

53 minutes ago, Ian Foster said:

Phil, I don't suppose you put a dial gauge on the diaphragm fingers to check for run-out. That's the only thing I can think of that would wobble the release bearing! BTW I do have a serviceable Classics Clutches (B&B type) and a new 10 spline plate available FOC if you are need. (I'm in Wareham, Dorset).

Ian, Thanks for the generous offer, Ive had a day away from the garage today so no progress. Will check the fingers tomorrow and see what I find.

Following everyone's advice I now have a number of things to check/change/repair before reassembly and I am hoping together they will address the problem.

 

[Phil C]

38 minutes ago, johny said:

It wasnt the dowel that was the surprise but the oversize dowel bolt used in one of the positions (5 oclock?) to bolt the gearbox on and act as a second positive l

Correct. In my case the o/s of the two lowest engine plate holes suits a 3/8" bolt/dowel rather than the 5/16" for all other fixings.

[Ian Foster]

44 minutes ago, Phil C said:

the oversize dowel bolt used in one of the positions (5 o'clock?)

Something else to check (and worry about).

[Iain T]

2 hours ago, Phil C said:

Will the split pin not restrict the carrier movement towards the gearbox?

Phil, sorry had a senior moment I used a roll pin. 

[Ian Foster]

1 hour ago, Phil C said:

Will check the fingers tomorrow and see what I find.

Phil

I'll keep an eye on the Forum tomorrow and if needs be we can get the clutch down to you PDQ.

As the RBRR is fast approaching, this needs to be fixed.

Ian

[Iain T]

1 hour ago, johny said:

wasnt the dowel that was the surprise but the oversize dowel bolt used in one of the positions (5 oclock?) to bolt the gearbox on and act as a second positive location point for it....

It was the chap at Canley Classics that diagnosed it from 150 moles away! A big thank you to him. The oversized hole in my bellhouse was caked in rock hard crud and I had to chisel it out to clear. 

I used a dti on a mag base stuck to the flywheel and measured the run out of the gearbox location hole at the back of the bellhouse. I rotated the flywheel and was somewhat alarmed at the near 30thou runout! Anything over 5 thou can cause a problem. 

Norra lotta people know that..... 

Iain 

[Pete Lewis]

when installed the carrier is miles away from the gearbox using a   3mm  split pin wont cause any problem 

unless you got one from the Titanic or Queen Mary 

do make sure you find the 3/8" hole   its so important 

Pete

[Phil C]

11 hours ago, Ian Foster said:

Something else to check (and worry about).

Tell me about it…..😫

11 hours ago, Iain T said:

Norra lotta people know that...

Clever stuff! Makes me feel like I don’t know what I’m doing!!

10 hours ago, Pete Lewis said:

do make sure you find the 3/8" hole   its so important 

Found and 3/8 shouldered bolt awaits reassembly 👍

Silly question but should the thrust bearing be greased?

It looks like a sealed bearing but the WSM talks about pressing in grease?

thanks all 

[Pete Lewis]

they have been a sealed bearing for many years 

some grease on the front cover aids the slide of the carrier , but will attract dust and that can cause sticking later on

many advise dry assy more modern are often plated to help , not on triumphs of the era

a smear of clutch grease or anti seize on the input shaft splines but sparingly 

[Ian Foster]

3 hours ago, Phil C said:

Clever stuff! Makes me feel like I don’t know what I’m doing!!

Phil

Have you been able to check the clutch diaphragm for runout.

The oscillating bearing/carrier was your original problem, which could be related to a lack of dowel alignment of the bellhousing or the clutch itself.

Clutch cover, plate and GT6 standing by, in case delivery to Lyme required. RBRR looming!

Ian

Edited September 29, 2023 by Ian Foster
update

[Phil C]

Ian, 

Not done yet, flywheel still off. Just replaced spigot bush…as I was there.

thinking about alignment - the back plate has only one locating dowel and there is no dowel bolt listed. How can I be sure this is aligned correctly? Some of the retaining bolts are fully threaded - should they be shouldered for better locating?

As I am in a position to deal with this now it would be good to confirm or otherwise.

phil

[Ian Foster]

Phil

Not quite clear from your previous posts, but have you found the hole for the 3/8" bolt at the bottom and do you have the dowel at the top?

Ian

[Iain T]

Normal bolts have a non threaded length so they will do. Don't get worried about a couple of thou a normal 3/8" bolt will suffice. If you are concerned and have a vernier measure the plain diameter of the bolt. I think the rest of the holes in the bellhouse are 5/16" clearance so will allow for some rotation. 

Iain 

[Phil C]

Sorry not too clear

I am now referring to the engine back plate. If the bell house alignment is crucial then the location of the engine plate must be too.

the parts book lists two dowels but I only see one. 8 o’clock on photo.