BruceWard

Ok, the clutch is off now and I have more pics. Before anything else thanks for walking me through this and Ill keep the pics online for future reference.


As predicted the clutch was shredded




Here is the pressure plate, which has several grooves worn into it.




Here is the fork




Now the flywheel, I dusted it with a shop towel and felt of it with my hand. It is very smooth with no grooves. There are color bands, but they are not grooves.








And as a Bonus Question how does this O2 sensor look




So I am going to buy the equivelant of the Pelican Parts kit from Zims. With all the parts Raj suggested previously and the master and slave cylinders. I have a local shop that can resurface the flywheel or Zims can do it if I ship it to them. But I am leaning towards leaving the flywheel alone. The flywheel feels perfectly smooth to me.

So what do you think?

BruceWard

These are the parts I plan to order, is there anything I should add or subtract?

clutch
pressure plate
release bearing
throwout arm shaft
needle bearings x 2
master cylinder
slave cylinder
release bearing guide tube
pressure plate bolts
pilot bearing

Jay Wellwood

'And as a Bonus Question how does this O2 sensor look'...

aaaa.....like a used O2 sensor.

Seriously, how many miles since it was replaced? When I replaced the O2 sensor on my 928, it looked alot darker as I recall - but looks may be misleading.

About the only way to gauge when to replace the O2 sensor is based on performance - which is hard to judge unless you a an Air Ratio meter (read voltage bridge divider with pretty LED's), or observe the O2 sensor output using a voltmeter.

Don't know about the 968, but on the 928, the O2 sensor provides feedback to the LH unit as a 'fine tuning input' for maximum emission efficiency while permitting max available power output under normal driving conditions. The O2 sensor is bypassed under WOT conditions as emissions are not as much of an issue.

If you replace - ~$100 each. Depending on how hard it is to access, you might consider it as a WYAIT item.

RajDatta

I would change the needle as well. It has grooves from the bearings and it would give you a very unpredictable release. Definitely change the needle, pop the needle bearings out of the fork and check to see if the fork has grooves as well. I might have some of these pieces handy if you need them.
If flywheel feels good and if thats the side that still had the disk material, I would leave it alone as well, unless you are in a mood to be daring. In that case, go ahead and change the main seal on the crank as well.
O2 sensor looks fine.
You can only get to pilot bearing if you remove flywheel. If you don't plan to remove flywheel, no need to order that.
Raj

BruceWard

The flywheel side of the disk was intact and its smooth so Im going to leave that alone and plan to reassemble from here.

I took some pictures of the fork with the bearings removed. The inside of the fork is smooth, but there is some wear on the ends and strange wear on the side.









wear on the side

RajDatta

Thats normal from the release bearing making contact to it. Did you feel the grooves on the needle from the bearings?
I will try to compare it to my release bearing tonight and let you know if the wear is severe.

BruceWard

Raj, the needle is certainly one of the parts to be replaced. The fork is $250 from Sunset and a couple of weeks wait for it. Zims frequently rebuilds forks for 944s and offered to rebuild mine to match up with the new release bearing they will be providing. When the fork in its current condition is mated to the release bearing the bearing can turn about 1/4 inch each way. Zims believes that is too loose, can you confirm?

BruceWard

Back with more quesions but no pictures this time. Can anyone point me to torque specs for the flywheel and clutch bolts.

I bought a short 12mm cheesehead and am going to take the flywheel bolts out tonight. I loosened one earlier and the tool worked well. Those bolts are on there tight though.

Assuming it comes off ok it should get resurfaced tomorrow and the big box from Zims should arrive on Saturday. Anyone have tips for reassembly?

RajDatta

Bruce, are you doing main rear bearing and pilot bearing? I am going with memmory but they are in the 65lbs/ft range. I will verify tomorrow.
Make sure you get them in good before you attempt to turn them, very easy to strip them and then you will need to remove bell housing.

BruceWard

The flywheel came off easy in about 45 minutes. I may have found the magic tool for removing the 968 flywheel. I purchased a set of 4 - 16mm cheeseheads off of Ebay, each one is about 1.5 inches long leaving plenty of room to reach all the bolts on the flywheel.

There is one more set on Ebay, but if there is interest I see a group buy coming on these!
Ebay

I will be changing the pilot bearing, what is the rear main bearing?

I do not plan to change the seal, it appears sealed and I hope to keep the rest of the car intact.

Here are some pictures of the progress


Face of flywheel with the long 3/8th ratchet I attached vice grips to. I needed the vice grips to get enough leverage. These were a lot more difficult to break loose than the crank bolt!


Rear of the flywheel.


The void it all came out of


The set of tools that made it all possible. Not a single bolt was stripped.

I almost bought a bolt out set at Sears just incase, but it would have been a waste of money.

RajDatta

Bruce nice job there. I meant seal, not bearing . Those are some nice looking cheeseheads. The rear main seal is right there but sometimes as they say, "if it ain't broke, don't fix it".
Seems like you should be okay about everything. Good luck with the install.
Regards.

Darth Coupe

Bruce, it seems that I have the same exact failure as you had back in January. I can see shredsd of clutch disc coming out of the seams of the clutch assembly. Right now I am at the point where the window is off, and the needle is out of the fork. I am about to undo the bolt in the shaft in the torque tube, but it of course is not facing down. Any tips on rotating the shaft clockwise to get at the bolt as there is a lot of resistance and I do not want to force anything.

Right now I am thinking of getting the parts I need off of an ebay auction: ebay link. Does this auction though seem shaddy to you as it lists both 944 turbo and 968 on the same auction? I know there are different parts and that is why I am asking the guy to confirm, still waiting on the email. I would go and get the parts from Sunset, but it will take so long to get here. The other option I was considering was Paragon, but the price difference is quite substantial.

Also, it I think I will be off to getting in the zone soon for some triple squares. Any ways, I may be emailing you on your personal experience on this job soon, maybe Raj too, just probably after the cookout weekend.

Any thoughts on what got in there to shred our discs? Mine happened at Mid-OH after a down shift, but it did shift once and then never again. My clutch pedal was then solid like yours, I am thinking a throw out bearing or fork as the fork was stuck on the wrong side and it slipped off of the release bearing.

BruceWard

If you remove the plugs it will be much easier rotate the crank. I had the middle drip pan off and a ratchet hanging off the crank bolt most of the time I was working on the clutch. My wife rotated the crank while I watched for the bolt to come into view.

If you want the 20 piece kit I would buy it from http://www.pelicanparts.com/catalog/...clutch_pg1.htm but if you want to stick to what you need then http://www.paragon-products.com/category_s/119.htm is a good source. You do not need the alignment tool as it does not work for the 968. It sounds like your master and slave cylinder are ok and they are changed from the outside so you might as well save those $s for now.

Darth Coupe

Well, it was definately the clutch. I got it out yesterday and the inner disc is fried. I can take pics later. My question now is where to take my flywheel to be resurfaced. It is in good shape, just want to make sure I cover all of my bases. Also, I stripped one of the clutch bolts when removing it from the flywheel, even with the nice new triple squares I got from Autozone. I was able to cut the head off with my dremel, now I need a replacement. While I am at it, I may just as well get the other 8 as well. Any recomendations on where to get these bolts?

BruceWard

I bought new bolts for the flywheel and clutch from Zims, doing it agan I would buy from Paragon but thats just because I buy everything from Paragon now. Neither Zims or my local resurfacing shop would touch a DMF. So mine was slightly retouched with steel wool and reinstalled.

David at http://www.specclutch.com said he can resurface a DMF for his customers. If you do not find someone locally then perhaps you should try him.