Clutch still good?

[Swallowtail]

Hi,

I would appreciate opinions on the condition of my clutch. Car is a '73 911t. Clutch disc thickness is about 7.5mm (0.3").

What do you guys think?

[wareaglescott]

IF you are questioning it, and you have it that far apart I suspect you know the smart way to go here!

[Swallowtail]

Thanks for the reply - I have really no idea on how to assess the condition - that's why I'm asking. For example how can I tell if the flywheel is still good?

[Swallowtail]

By the way - the number on the clutch disc is 1861759035. This Sachs part no. is still valid but the discs look nothing like this. Is this the "old" style from many years ago?

[proporsche]

your clutch disc is more likely sport racing clutch not a regular clutch disc..i would put stock in it Remove the TO bearing and inspect the press.plate the flywheel looks ok so is the face of the pressure plate.

Ivan

[gomezoneill]

The flywheel and PP look like they got overheated I see blue.

[proporsche]

gome..that is usually from this kind of disc very hard material..i`d say it is ok....no cracks

[r lane]

That is a hot rod type disc. Rust at the release bearing and PP finger connection. Probably the bearing and that in turn will have grooved the fingers

[Marc Bixen]

Man that's a strange setup. Yea I agree it looks "Sport", but I've never seen a disc like that.And if it were a sport set up, why doesn't it have an Aluminum PP? Anybody have further info?

[reclino]

The disk looks like a centerforce. The factory repair manual will have a thickness spec for new, and a min thickness for wear limit. Some of the Sachs sport pressure plates require a thinner friction material and spec out a different friction disk. 1973 911t I just looked in the manual I have and no thickness is called out. The manual nInha e for the 930 lists this. Strange.

[walt]

I have an old post by Warren Hall who has the 70-74 disc thickness limit at 6.0 mm.

[Walt Fricke]

I'd reuse the flywheel and pressure plate, and as others suggest replace the clutch disk with something more normal, and the TOB just because it is all apart. Yes, signs of local overheating, but the rap on that is that it hardens those areas more than the rest, so they don't wear as much as the rest and end up being high points. There doesn't appear to be the grooving I take to be a sign of wear.

On the flywheel, you can compare the depth of the wear surface with the depth of the area where the PP bolts on - as that area doesn't wear. If there is no lip, so to speak, between the two, you don't have plate wear.

[RedCoupe]

I tend to not reuse pressure plates as I've had experience in the past with the diaphragm springs losing their tension over time, particularly if they have gotten hot a few times. I just haven't been able to get a long life out of a new clutch disk if I don't also replace the pressure plate.

[Swallowtail]

Thanks guys, I will get the full clutch kit (surprisingly affordable compared to my 993) and ask the machine shop that does my engine parts if they can resurface the flywheel.

Still, very strange that nobody has seen this clutch before. A Sachs Race clutch should have other numbers on it in my opinion.