At 09:16 AM 10/11/2007, Mike LaBranche wrote:
>First, thanks to all that have helped with info, technique, etc on
>getting this clutch out. I still don't have it out, but I've made
>progress. I have the pressure plate pins shimmed. I've unbolted the
>pp from the flywheel. I still can't get the pack to drop out. The
>pilot shaft is simply too long no matter what position I get it in
>fore/aft relative to the pack. After looking at some pics on the forum I think I know why.
>The pics show a gap at the bottom of the bell housing where the TT and
>the pilot shaft join via the coupler. My bell housing has a beam
>running across that gap which is blocking the aft end of the pilot
>shaft. Herr Kempf has suggested unbolting the bell housing from the
>block and sliding it back an inch to gain the clearance required. I
>have to yank the housing anyway to do the ball stud drill/tap dance
>anyway but I ran out of steam last night so I'll try that tonight.
>Man, this beast has really been kicking my butt. Remind me again why
>we love these car? lol
few additional items that'll hopefully make the job go easier:
1. Before dropping the clutch out , mark the fly wheel/intermediate plate/pressure plate for balance orientation. May not be a big deal.
2. When installing, first thing I do is hang the assembly by the clutch lever off the plastic bushing.
3. The '79 uses the disc centered vs. the pin centered method. The flywheel has a slight recess that lets you get things right.
4. When initially orienting things, make sure the nose of the intermediate shaft properly engages the pilot bearing.
5. Also at this stage, make sure the guide sleeve is forward of the attachment point on the casting. It's too dang easy to get the thing behind it.
6. When you get to connecting the clamping sleeve, do the forward bolt first. When aligning the hole for the aft bolt, you'll actually need to withdraw the shaft away from the pilot bearing. This slight movement places the nose of the shaft properly inside the pilot bearing. Not to worry.
I just did my clutch on my 81. First time ever. A few tips from others I used:
1) You don't have to unbolt the starter from the clutch cover plate. Actually easier if you leave on
2) Don't drop the clutch on your head, it hurts a lot and leaves a big bump.
3) You must remove the coupling shaft bolts completely in order to slide the coupler back. Be careful that the rear block holding the bolt has not broken it's tack weld or you may be fishing the block out of the torque tube.
4) Once the clutch cover plate is removed, mentally note or take digital pictures of the location/spacing of coupling plate. This will remove any doubt when reassembling.
5) Using the 3 coat hanger spacers on the pressure plate helps a lot.
6) Wearing gloves you can spin the engine using the starter ring. Spin only in the proper direction unless you are 100% certain your timing belt is tight and won't jump while spinning wrong way.
7) Use chalk or scratch to mark alignment off all components to each other. Helps with re-install.
8) Don't forget to grease everything according to manual.
9) The snap ring holding the release bearing is a pain. Have patience.
10) transfer the balancing marks on the discs to the other side of the discs, otherwise you can't see them when installing.
11) Using heavy grease to pop out pilot bearing did not work for me so I fashioned a bearing puller from a carriage bolt by cutting the head down so it fit in the bearing. Then used a larger socket over the bearing with the head of the carriage bolt inside the bearing. Screwed a nut on the other end of the carriage bolt protruding thru the socket. Cranked the nut and the bearing popped out easily.
12) Make sure guide tube is on the proper side of mounting holes when lifting up new clutch assembly. A floor jack helps with the re-install.
13) Because my exhaust has no catalytic conv. I left the exhaust on. This required me to fashion a long punch to tap the 3 alignment pins back in after the new clutch was installed.
14) Use a bar clamp to engage the clutch then before the two disc spacing alignment by prying the 3 t-bars.
Use a screw driver gently to make sure the clutch discs are resting as far back from the intermediate plate when checking the spacing between the discs and the intermediate plate.
15) Replace the ball cup on the release arm while your in there.
16) Make sure you don't engage the clutch when the slave cylinder is not installed fully. You will pop
out plunger. When bleeding the clutch, push the
slave cylinder in by hand to pump trapped air out, otherwise you may bleed, and bleed, but never get a firm clutch.
Good luck. It's really not that hard.
Nice list, Eric. Got a few adders:
17) Bleed the clutch before installing the slave.
This is done by pressing the rod fully in and holding it there. A balancing act to have the assistant press the pedal carefully while you crack the bleeder. Tip the cylinder so the bleeder is up. A few cycles and you'll have nailed it.
18) The slave cylinder lines and starter block access to the bolts. To get them on attach the lower cover to the bell housing using just a few threads on the forwards bolts. This leaves access space for getting to the bolts.
19) In the absence of the prescribed dry moly spray, dry graphite spray may be used.
20) Lifting the clutch into position may be troublesome. Seems the arm catches and can not be worked through the hole to the stud. Takes a multi-stage approach of lifting, adjusting the guide tube and the shaft and working (repeat) the arm to make it go. Won't just go up in one motion.
21) The front bearing in the torque tube may have walked forwards. This can prevent the clamping sleeve from going back enough. With both bolts out, just force it.
Anyone else have some tips?
The clutch has some leaf spring that help to center the intermediate plate.
It is possible to remove it without trapping the springs but it certainly is easier. Also, THe central pilot shaft needs to be slightly withdrawn so that it isn't stuck in the pilot bearing in the flywheel. Either can hang the clutch pack up. Also, the whole mess is HEAVY and awkward and normally is right over your face while messing with it. Cut a 2 x 4 (or a 4 x 2 for John Holdsworth ;)) so that it pinches between the ground and the starter ring to support while you are freeing it up. You can also use a jack if you're good.
To trap the leaf springs you need to compress them and then trap shims under the heads of the rivets that stick out of the back of the pressure plate (3 equally spaced). This can be done by prying and putting 1/16" dia music wire under the heads. These should look like the kind of staples that you bang a cheap crate together. Like a capital "U" where the width between the open end just fits the shank of the rivet. Compress the clutch with channel locks or vise grips so that you can get the shim under the head and then rotate the clutch pack so that you can do the same to the next 120° away. Continue on to the third. Then make sure the clutch pilot shaft is withdrawn about 1/2" axially and it should all come right out.
Next, if you can get the ball stud remains out you are lucky. I wasn't. I had to pull the entire clutch housing. This was accomplished by removing the tranny from its mounts and pulling it back about 3" so that I could pull the entire bell housing out to have the face spot machined and re-tapped. I removed exactly the thickness of the washer that fits the new stud size so that it would end up at the same height. Then I locktited the ever living bajeezum out of the thing when I put the new one in. Fortunately the new stud is made with larger threads so that you can just drill the old one out and re-tap.
Make sure you check your pilot shaft for wear. Also, I used a clutch kit marked for use on 1980 through 86 cars on my 79 and it worked great. Still going and it was about 1/3 the cost of buying parts for the 78 79 cars.
Also, buy some moly-di and carefully lube any metal to metal contacts in the clutch assembly while rebuilding. Make sure you make the center plate adjustment as well. I do it by just pulling the three little intermediate plate stops back about 1mm as I am reassembling everything. A trick I got from my dusty old 4 vol manual set. Works great.
Hope all this makes sense.
Make sure when lifting that the lubed pilot shaft doesn't move fore or aft on you. It has to be just flush to the front hub on the front side or the assembly won't go. If it move you have to come down and realign and go back up. Better than doing one armed bench presses :) jfk
... You should be able to get the coupler far enough back onto the
drive shaft until you see the splines on the end facing the clutch. It
can be hard to push the coupler back because it is retaining some clamp
force. Like Jay said, use a large screw driver, or brass drift if you have
one, and hammer it back into the torque tube being careful not to get too
ham-fisted. With a few careful blows, you should be able to get the
actual clamp (that the bolt goes through) to loosen it's grip on the sleeve.
Then you know you've got enough room to slide the whole sleeve/clamp back further on the drive shaft...
Hope that some of this helps!!
There are some differences from year to year - It helps to always give the info on your car.
Your questions are covered pretty well in the Factory Workshop Manuals - are you attempting to maintain a 928 without having the manuals? That makes it very difficult, and opens the door for a LOT of potential errors.
Pilot bearing installation:
- Remove old bearing. This can be done with a bearing puller, by making a puller from a bolt and washer, or by filling the opening with grease and driving a shaft into the opening, forcing the bearing out with hydraulic pressure.
- Tap new bearing into place, flush with surface.
- The pilot bearing should be packed with grease.
- The splines get lightly lubricated with OptiMoly.
- A tiny bit of grease on the push rod would help.
- A tiny bit of grease where the arm touches the throw-out bearing would help.
You do not want to put enough grease to risk having any get onto the clutch disc/discs.
Dual 85s Clutch Pack Install Tip
Setup the disc's as per removal & manual, intermediate plate, pilot shaft, throw out bearing & arm assembly. While it is setup on the bench, place a couple of pressure plate bolts in to just hold it together and lined up good. Take a length of mechanics wire, double it up and then some, run it through the holes where the pins go, tighten it up with a pair of pliers, really good. There are 3 of them. This will hold the pack together during installation, much, much easier. There is a space in the intermediate plate where the pin is visible, so the wire can be removed easily, after you put a few bolts in the pressure plate to hold it up in there. Once you get a few bolts in and lined up, cut the wires, install the pins.
If you doing this on your back as I was, I cut a 5" length of 2/4, get a 1/2" round wood chisel and cut out a groove in the wood, 1" deep, 4" long. Put on a small jack and place the clutch pack in it, jack it up into place. Make life a lot easier.