StandardShift.com

I'm tearing apart my wrecked Escort and took the clutch apart. I was wondering how thick the fiction disc is supposed to be (when new). I measured a thickness of 8.5mm overall, 3.5mm on the flywheel side, and 4mm on the pressure plate side.

Here are some pictures:
http://photos.douglasharrington.com/mai ... ewsIndex=2
http://photos.douglasharrington.com/mai ... ewsIndex=2

As far as I know, that's the stock clutch. There are 145k miles on the car (45k of my driving). I'm just curious as to how much life was left on the clutch.

I was amazed at how thin a good clutch disc is. I figured they had to be twice the thickness of a brake pad. When I did my project and took the existing clutch disc out I figured it must be worn out. I bought a new one and it was the same thickness! (I did buy one a little larger diameter to better match the rest of my vehicle.)

The "old" one I have is 7mm thick. I think the new one might be 7.5 or 8mm. Obviously different clutches will differ (duh) but I suspect that your 8.5mm is like new.

There's plenty of photos of both of mine at https://picasaweb.google.com/Perforated ... nsteinberg#

This one is an on-edge comparison of both:
https://picasaweb.google.com/Perforated ... 3375060914

Old one:
https://picasaweb.google.com/Perforated ... 3545167314
https://picasaweb.google.com/Perforated ... 8223382226
https://picasaweb.google.com/Perforated ... 7538963474
https://picasaweb.google.com/Perforated ... 3089917762
https://picasaweb.google.com/Perforated ... 0671596530
https://picasaweb.google.com/Perforated ... 4865198962

New one:
https://picasaweb.google.com/Perforated ... 6534444770
https://picasaweb.google.com/Perforated ... 0544146274

I forgot, are you going to have another Ford? Save that clutch disc, it's good enough to install and use.

Well then, I guess this should be a good thread for all the newbies who have clutch phobia. This was my first standard car, and I obviously didn't put much wear on the clutch for the mileage on it. I thought for sure it would be almost done when I took it out. Note that I do a good deal of highway driving, but I do drive about 20 mi a day in the city (Boston), frequent stops, hill starts, etc. When I was learning stick I managed to do a hill start in 3rd gear by accident on that clutch disc. That was about the worst thing I ever did, and I lugged it more than I slipped the clutch. Obviously it didn't care much.

I did buy the same car again (same year and color even, how cool is that?) So you really think it's wise to reuse it if I ever have to put a clutch in the next car? How about the pressure plate? There are noticeable grooves in the fingers from the throwout bearing. I thought that was one of those things everyone advised against doing since it is so much work to pull the tranny.

That's a good point about the work required.

I saved and intend to use the old clutch disc if I ever need to replace mine, but my RWD transmission is probably less work. My plan (if ever necessary) is to just slap it in and see how it drives, not even get the flywheel resurfaced. I think I can change the clutch in a few hours of work without a helper. If I had a garage, a transmission jack, and a non-hacked input shaft I think I could do it in an hour.

Even so, that clutch is probably like new. I'd save it all, especially the flywheel; that way you can not only have spare parts, but you'll be able to get the flywheel resurfaced ahead of time instead of leaving the car apart while the flywheel is in the shop.

Yes

About reusing the clutch parts: What about the pressure plate? I noticed the fingers have a groove in them from the throwout bearing. If I'm not mistaken, when the clutch pedal is depressed the throwout bearing is pressing against the fingers, and the bearing itself is rotating along with the pressure plate and fingers. So, why is there a groove as if the pressure plate fingers were slipping against the bearing?

Just wondering how that works and why there are grooves.

Can you post a pic of that?

Your understanding of how it works is correct. I guess a seized release bearing could do it pretty severely. I don't know but probably in the long term the normal slippage that happens when the bearing first makes contact with the fingers could do it.

Here's what it looked like from the S10:
https://picasaweb.google.com/Perforated ... 8703540338
https://picasaweb.google.com/Perforated ... 4406318354

Pressure plate:
http://www.photos.douglasharrington.com ... 3.jpg.html

Throwout bearing:
http://www.photos.douglasharrington.com ... 4.jpg.html

One last pic of the whole assembly:
http://www.photos.douglasharrington.com ... ewsIndex=2


The bearing wasn't seized. The grooving isn't severe, but enough that I can feel a ridge is there. I suppose it's normal then. Would you say the pressure plate is safe to reuse? I guess the only concern would be the grooving getting deep enough to start snapping the fingers. If it's just becoming noticeable at 145k I suppose it could last at least another 100k+ before it's an issue. I would of course replace the throwout bearing and pilot bearing. The flywheel looks fine from what I can tell. I imagine I would only have it resurfaced if I were to replace the clutch disc.

Someone else will have to take that question, I don't know if that's too awful. I think it doesn't look as bad as mine did. I'd reuse it, but as I said, I think mine is pretty quick to change.

So that was all after 145,000 miles? Nice!

Marks from the release bearing pressing/scrubbing against the diaphragm spring fingers look normal to me. Even if the bearing is constantly in contact and spinning in unison with the fingers, it still has a radial sliding motion against them every time the clutch is released or engaged. That is why either the bearing face or the spring finger tips are radiused (one or the other, not both).

Rope-Pusher wrote:That is why either the bearing face or the spring finger tips are radiused (one or the other, not both).

Uh-oh...I think mine are not.
https://picasaweb.google.com/Perforated ... 8366541362
https://picasaweb.google.com/Perforated ... 2093667026

Photo doesn't seem to show tops of spring fingers as being radiused, but they might be tweaked enough to provide a rolling contact area.