checkmate1996

Guys/Gals,

I just got done replacing my pilot bearing. I wrote down some quick pointers. Sorry no pictures but just wanted to share...

Quick notes on clutch job
Tools Required or to atleast make life easier and less cussing!

• 2 lb sledge hammer - Helps drive pilot bearing in and clutch centering pin
• Block of wood - protect pilot bearing while trying to get pressed in
• Small ball peen hammer - once pilot bearing is seated use this to put the final touches on
• 1/4" punch - to Drive centering pins in and nice heavy swing on the hammer!
• Wedge - remove centering pings
• ring gear wrench
• 3/8 torque wrench - pressure plate to flywheel - 16 ft/lbs
• 3 metal clips to hold the pressure plate, clutch fork, TO bearing in an engaged mode prior to removing
• Various assortment of extensions for ratchet drivers and drivers
• wratchet wrenches
• 8M Allen head
• most socksets are 10m, 13m
• pilot bearing puller
• If you pull the flywheel, you will need a 12pt triple square found at Autozone or NAPA
• Assembly lube - put on the intermediate shaft prior to re-installation
• Grease - put a thin coat on pilot bearing prior to pressing in flywheel
• Shop Towels - for getting assembly lube off of you
• Crowbar / Tire Iron
• nail polish - to paint the backsides of the clutch discs - helps with reinstallation and alignment
• A good attitude!

Points to remember - No Particular order

• Have workshop manual to compare tolerances
• getting the clutch centering pins in and out are a pain
• Helps to have two people - this avoids swearing and growing a 4th arm
• be careful the clutch doesn't drop on you when taking out - it's 25lbs or so feels like it!
• Note the painted marks on the clutch disc - they need to be reinstalled opposite of each other to balance out
• Two versions of intermediate plates exist, you must gap to see which one you have.
• Don't worry about getting the clutch fork attached till everything is tightened up. It's easier to use the crow bar/tire iron as their is something to put pressure against
• make sure the intermeidate shaft guide housing is not put on the wrong side
• don't forget to take out the 3 clips keeping the clutch engaged
• Last step - rotate the ring gear several times and check the intermediate plate adjustments while the clutch is engaged AND disengaged - while disengaged check spin the shaft to check that clutch disks spin freely and have even gapping.
• button everything up!
• Go drive ...er or put the headers back on! uggh!!

vanster

I would be very very careful about using a 12pt triple square from Autozone or any of the low end tool suppliers. If you strip or round off one of the bolts or worse, you are pulling the motor. My suggestion is to invest in Snap On or Maco or similar
I have an 80 with a single clutch, you might consider this option at this point
Much easier to change and set up.

medipedicman

Thanks Checkmate. I have had the clutch with the resurfaced discs on my bench for three weeks. Hopefully my helper will be here this morning to get it back on the 79.

hacker-pschorr

Pilot bearing......
Put it in the freezer days before the install, it will literally slide right in.
Instead of a block of wood, use a socket that is the same size as the outer race.

getting the clutch centering pins in and out are a pain
I must be having a brain fart, I cannot picture what these are or having to mess with them.

Small ball peen hammer - once pilot bearing is seated use this to put the final touches on
Again, use a socket......

Assembly lube - put on the intermediate shaft prior to re-installation
NO - splines call for Moly Lube or Moly Grease. Most auto parts stores carry some.

Two versions of intermediate plates exist, you must gap to see which one you have.
I thought the only differences were the pins that go to the pressure place, and those can be hammered out.

don't forget to take out the 3 clips keeping the clutch engaged
After everything is installed and torqued to spec

Last step - rotate the ring gear several times and check the intermediate plate adjustments while the clutch is engaged AND disengaged
Just need to make sure the intermediate flywheel is centered between the discs when the clutch is disengaged. Use a screwdriver, keep your fingers far, far away.

3 metal clips to hold the pressure plate, clutch fork, TO bearing in an engaged mode prior to removing
If you skip this step, you can easily use c-clamps or a bench vice to press the pressure plate apart and install a shim.



+1
This is where I use a baby sledge, on the 12pt to "wake up" the threads. I've never had an issue getting these out.

The double disc clutch is not that bad. It's far superior to the single disc.

GlenL

Good points above.

The three centering pins are essential. They are difficult to get in/out. Don't deceive yourself that the bolts will center it right. That assembly is turning fast and any off-center assembly will result in vibration.

toofast928

1980 had a single disc? or was it converted some how?

Ducman82

"Two versions of intermediate plates exist, you must gap to see which one you have.
I thought the only differences were the pins that go to the pressure place, and those can be hammered out."

mine has pins, and they are snug fit, but come out and go in with no hammering.

medipedicman

I posted this on my projects thread (https://rennlist.com/forums/928-foru...-2-of-3-a.html) but did not get any feedback yet. I thought you chaps might help, thanks

We reinstalled the clutch today with resurfaced discs and smoothed out plate. We reinstalled the slave, bleed it and then put the starter back on. Everything shifted great on the jack stands and while the idle was very high we decided to take it around the block for the first time in a couple of years.

The 79 was in the garage and facing the road. We exited right, which is downhill. Powered to 3000 rpm in first then engaged clutch as we approached a stop sign. Left the completed stop in first gear with no issues and slowly powered up to 3000 rpm and engaged clutch to shift to second. That is when we heard a loud rattle/vibration from under the shifter.?.?.? It kind of freaked me out so I did not attempt to complete the shift. We rolled for several hundred feet. During that time we noticed that the noise was only present when the clutch was engaged. I had moved the selector to neutral thinking we would just coast to a stop and with the clutch pedal up there was no noise but every time I engaged the clutch the noise would return.
At that point our momentum had taken us as far as it was going to so we faced walking back to the house and returning with the truck and a tow strap or just try to make it work. I engaged first and once the clutch was released it ran fine. Then going up hill at 3000 rpm I tried second. When the clutch was engaged/depressed the vibration noise was very loud. The trans shifted into second with no drama or grinding and when the clutch was released there was no more vibration.

This is my first clutch job and my buddy/helper is a gifted mechanic but no 928 specific knowledge or experience. Where should we start? With the car now back on jack stands we tested the slave cylinder again and it functioned properly. I will remove the starter, the slave, and the lower bell housing at some point this week. BUT, from there I have no clue where to even start. The man who rebuilt the clutch for me said that the throw out bearing was NLA from sachs or he would have gotten one for me. Could this be an issue with vibration? I see them on ebay for $35 all the time and I am sure that Roger could provide something for me.

I hope someone who reads this has a BTDT moment and can share some knowledge.

Thank you in advance

BTW: I was/am thrilled that we made it around the 1/2 mile block. It was very encouraging to see all of the work over the last two years start to pay off.

Dave928S

^^^^
Sounds very much like the throwout bearing to me, and that'd be the first thing I'd be checking.

I think Roger may have been rebuilding units as long as you provided a core ???? It'd be worth checking with him.

medipedicman

Thanks for the feedback Dave. I have another that I could swap in and see if it is any better. I would send one of them to Roger for a rebuild either way.

Thanks again for your help through the years and many 928's.

checkmate1996

+1 on the TO bearing. As my pilot bearing was going bad, I was getting vibration in the shifter all the time at any speed.

Also, the twin disc is a solid platform, it does require some training though which is sadly going away. However, it can handle some serious horsepower!

Yes, according the WSM, there are two versions which have a different tolerance set. Most likely this was the difference between 78-79 clutches and beyond.

If you don't know about centering pins...Uh oh!!

Thanks for the comments and other tips! keep them rolling...

hacker-pschorr

Looking through some threads I see what you are calling "centering pins". I never referred to them as that nor have I ever had issues with them.

Lucky I guess.

checkmate1996

WSM Clutches/Autos - 30-4 - Discusses the centering pins

WSM Clutches/Autos - 30-15 - Discusses differences in tolerances and intermediate ring

hacker-pschorr

Since they've never given me any issues, I never gave much though to the "offical" term. They were just always dowel pins to me.

Knock on wood it stays that way.....

checkmate1996

amen to that!