kylejohnston1

I am replacing the clutch in my 91 C2 and I am trying to decide what to do about the flywheel. This is my first time to replace a clutch, so I am not real sure what to look for on the flywheel. There are no cracks, but it apprears that there are significant heat markings to me. I've included pics of the clutch disc so everyone can see what kind of shape it was in as well. The clutch would slip badly under "spirited" acceleration in all gears.

Should I replace the flywheel with the clutch or just get it resurfaced? If resurfacing is the answer, are there any suggestions on where to get this done? I am almost certain I just have the standard dual mass flywheel...no light weight or aftermarket flywheel in the pictures, right?

Thanks for the help!

Kyle
Houston, TX

993Porsche

Although it looks pretty good, but I wouldn't chance it.


Ken

J richard

Hard to tell from the pic but it looks like you've run down to the rivets at some point and since it has a spring centere disk it's hard to say how many cycles are on it... I'd pull it and check it for flatness the condition of the dual mass and have it resurfaced. If it's light wear you can scuff it with a scotchbright pad and mount it up. But it's a pain to pull it all out again if it chatters on you... So I'd at least check it...Are there any ridges that are deep enough to catch a fingernail on?

Colin 90 C2

the flywheel looks like it may have some scoring. can you catch a fingernail on it if you drag it from outside to inside?
Do you have any rivets showing on the flywheel side of the clutch disc?

Indycam

I would leave it alone . The flywheel was not what went wrong .

crg53

There is absolutely no doubt, that flywheel needs to be resurfaced; what does the pressure plate look like? There is no sense in going to this length and not fix it right. Take it to an automotive machine shop for resurfacing and also to check the condition of the rubber in the flywheel.

BlueHeeler

It is somewhat of a philosophical question. Indy is right, ‘If it ain’t broke…’

OTOH how much does a new flywheel cost and how much is your time worth?

kylejohnston1

I've attached 2 pictures of the clutch disc on the flywheel side. I've been able to drag my fingernail across the flywheel without snags. I think I'll play it safe and have it resurfaced assuming it is still within spec.

Anyone know the minimum thickness for the flywheel?

J richard

That's really the right thing to do. You should have the dual mass function checked out as well they do fail, and if it's not a LUK or it has more than 75k on it I think you're on borrowed time anyway. I wasn't clear in my first post, but you have a spring centered clutch, which means at least the disk has been replaced, so unless you know for sure the pressure plate and flywheel may be on their second cycle and should be checke pretty carefully. If you do reuse them you will want to replace the pilot and throwout bearings, and the guide tube and fork needs a look as well.

It's always a crapshoot with reusing parts, takes a bit of experience to know how long it's going to last. Porsche used to make these great little booklets that had all the wear tollerences for each part that were great to make the call. Took the guesswork out of it, you have to go to the full manual(s) for the 964.

springer3

I doubt that is the original clutch. My guess is someone before you replaced the clutch that left those rivet marks without refinishing the flywheel. Do not repeat their mistake. Get a competent machinist to look at the flywheel, and refinish or replace it as recommended. The machinist will be able to tell if it is warped or has hard spots from overheating. It looks refinishable to me, but you can't really tell from the pictures.

Colin 90 C2

after looking at the disc pictures, I have to agree with Springer. Someone previously replaced a disc that was worn down to the rivets.

If you slipping now, then at minimum, you need to replace the pressure plate. The disc actually looks reusable, but then you're only saving $80. What's peace of mind worth?

I can't find a tolerance dimension for the flywheel. Is there one imprinted on the unit?

I think you can pick up a the lwt setup for around $1100. At least that was the price a few years ago.

A machine shop should be able to advise you on resurfacing.

3blackbirds

I'm going to be looking into this project in a few months as well. I'm getting slipping, but not in all gears. I was told from my local dealership that the flywheel can not be resurfaced, but if I were to decide to try to get it done, the people that would touch it are few are far between... From reading this, it can be resurfaced?

Colin 90 C2

slipping is usually an indication of a worn clutch disc. Once it starts to slip, replace it so you don't score your flywheel.
Common wisdom, as I have learned, is to replace the Pressure Plate, the clutch disc, and the throw-out bearing, at the same time. That was with any type of car, but with the P car, you should also check out the guide tube and the roller bearings in the clutch lever arm.

kylejohnston1

I bought the car a few months ago with 135k miles so I am sure the clutch has been done multiple times. Once my flywheel removal socket comes in, I'll be able to do a more thorough inspection. I was planning on buying the Pelican Super Kit ($1116) but I would much rather upgrade to the lwt setup if this can be done for similar $$$.

Colin, does your $1100 estimate above include flywheel and clutch?! If so, does anyone know where I could find those goodies?

It looks like Pelican is getting $1736 for the lightweight setup.

Pelican Super Kit:
http://www.pelicanparts.com/catalog/...Tclutc_pg1.htm

Pelican Carrera Cup Flywheel/Clutch Conversion:
http://www.pelicanparts.com/catalog/...Tclutc_pg3.htm

J richard

Kyle,

do a quick search here on rennlist, I can't remember which forum it was in, 964, racing or the for sale, but somebody had the whole LWF and clutch package for sale, lightly used for $900! I was going to get it just for the parts but you could use it. Even if you replace the bearing it looks like a great solution to your problem.