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UUC Motorwerks 8.5 lb Flywheel with e34 M5 Clutch

Warning: If you are not competent or do not feel comfortable doing any of these modifications or procedures, then please do not do so. I will not be held responsible for any damages caused by a result of your actions. Now on to the fun stuff!

First off, I'd like to say thanks to my Dad for all the help with the uninstall and the reinstall of the transmission and exhaust, and a big thanks to Dick King from King's Auto.

UUC stage II lightweight flywheel (also includes flywheel stretch bolts, two tubes of blue loctite, plate, and pressure plate bolts with lock washers)
e34 M5 clutch kit (includes pressure plate, clutch, and throwout bearing)
x6 Guibo (flex disc) nuts (BMW part # 07 12 9 900 047)
x2 Exhaust gasket (BMW part # 18 30 1 716 888)

Optional (* = pictured below)
*M3 slave cylinder (BMW part # 21 52 1 158 903) [recommended by]
*Driveshaft center bearing (BMW part # 26 12 1 226 731)
*M3 guibo (flex disc) (BMW part # 26 11 2 226 527) [stronger than standard]
*Bitch clip (BMW part # 25 11 1 221 849) [If you're slick you might be able to get it off. I broke mine the first time.]
Selector shaft seal (BMW part # 23 12 1 282 394)
Output shaft seal (BMW part # 23 11 1 224 779)
Input shaft seal (BMW part # 23 21 1 224 820)
*Rear main crankshaft seal (BMW part # 11 21 1 720 310?????)
*Selector rod joint (BMW part # 25 11 1 222 688) [eliminates shift slop, very difficult to replace with transmission installed]
Release Fork pivot pin (BMW part # 21 51 1 223 328)
Spring clip for release fork (BMW part # 21 51 1 223 234)
Pilot bearing (BMW part # ?????)
*Rear exhaust hanger(s) (BMW part # 18 21 1 723 101) [inspect, now is an easy time to replace them]
*Transmission mounts [easy time to replace]
ATF [required if replacing transmission seals]
Motor oil and filter [required if replacing rear main seal]

Jack and stands
Transmission jack or some means of supporting the transmission
Various Sockets and Wrenches
Various extension bars up to 36"
Torque wrench
Pivot to fit extension bar (may not be required, but I used one)
Torx sockets
Hex sockets
Pry Bar
Stiff wire
Penetrating oil (WD-40 or Liquid Wrench)

The following are required only if you are replacing any seals or the pilot bearing.
Pilot bearing puller
Small seal removal tool (a small screwdriver may work)
Brass drift

Air tools always help ease removal and installation


Exhaust and Driveshaft Removal

1) Raise vehicle, properly support vehicle, and remove wheels
2) Loosen and remove 6 bolts at the exhaust manifold to downpipe flanges (penetrating oil is recommended)
3) Lower exhaust onto crossmember
4) Remove center exhaust mounts
5) Loosen 2 bolts on each of the rear exhaust hangers and note their position
6) With another set of hands or a jackstand if close to the ground, remove the two hangers and lower the exhaust out of position
7) Remove heatshields to expose driveshaft
8) Check drive shaft for 2 white dots at connection. These will be used to reassemble the shaft after removal. If they are not present, remark and remove.
9) Loosen nut from guibo (flex disc)
10) Remove bolts from center bearing and carefully lower onto rear brace
11) Remove bolts from guibo and press driveshaft towards rear of vehicle. This should allow the transmission end to pull out of centering guide. Then remove the front half of the driveshaft. Be sure it's position is marked before removing.

Transmission Removal
1) Support transmission with jack or transmission stand.
2) Remove nuts from transmission mounts and remove bolts from support brace. Remove brace with mounts. (Now is an easy time to replace these with something like UUC TME's. I chose the red ones.)
3) Remove the speed sensor from the right hand side of the transmission. It has a wire which runs over the top of the transmission. You will need to remove it from the clips.
4) Remove the shifter knob by pulling straight upwards. Be careful not to hit yourself in the face. Then remove the boot and foam piece from inside.
5) Remove clip (aka 'bitch clip') from the carrier towards the front of the transmission. This will require lowering the transmission. I found that letting it rest on the crossmember did not seem to do any harm. The clip has a small tang on the right hand side which must be lifted before removal. To remove it, insert a flat bladed screwdriver under the tang and use another screwdriver to lift the clip. It's hard to explain, but just give it a shot. I had good luck with it the 2nd time I removed it. Then remove the entire shifting mechanism.

6) Remove 2 slave cylinder bolts and slide slave out. Support the slave with the stiff wire some place out of the way.
7) Begin loosening the 10 torx and 1 standard (it's facing the opposite direction) bolts holding the transmission in place. This is where that 36" (yes 3' long…) extension comes in handy along with the swivel joint. Be sure to support the transmission here to avoid stressing the input shaft.
8) Once all the bolts are loose begin removing them while supporting the transmission. Be sure to note the position of each.
There are 10 torx bolts and 1 small normal bolt holding the backing plate to the transmission. Once you are positive they've all been removed, use the pry bar to separate the transmission from the motor. There is a pin at the top left hand corner, so I'd recommend starting at the top. Then just slide it on out. (easier said than done) I'm sure I've left some small details out here as this really was not this simple.

Clutch/Flywheel Removal
1) Remove allen head pressure plate bolts. These are made of a very soft metal and tend to strip easily. I had no problems using the appropriate sized hex socket then tapping it into place with a hammer to be sure it is seated. Then zip it off with an impact gun.
2) At this point the pressure plate has probably fallen on your foot along with the clutch. Hopefully the pins with hold the whole works in place, but don't count on it.
3) Note the position of the tdc notch on the engine side of the flywheel.
4) Remove the flywheel stretch bolts and then pull the flywheel off.

*If you are not planning on replacing any of the seals you can skip these next parts.*

Before you go pulling all the seals out be sure you have the correct replacements. Now is the time to clean up the transmission if you plan on it. I used a little citric degreaser and water. It cleaned up quite nicely.

I must confess that I had some help from a mechanic friend with the seals. Thanks again to Dick King from King's Auto in Kent. He specializes in foreign auto repair and has a passion for the Porsche 356. He just about always has a 356 he's restoring along with some other interesting Porsche historical pieces.

Selector Shaft Seal Replacement
1) With a small punch, drive the pin out from the selector joint.
2) Remove the joint.
3) Using a small screwdriver or other tool dig the seal out (I was provided with actually a windshield trim removal tool. It worked quite well actually.) Be careful not to dig too far and gouge the inner surface. Look at the seal to see where the metal reinforcement is and shoot for that.
4) Once removed clean the area of any debris, lightly oil the seal, and lightly push it into place. Using a seal driver or similar tool (read: sized socket) lightly drive the seal into place.
5) Reinstall selector joint with a small amount of grease and tap the pin back in.

Output Shaft Seal Replacement
1) Mark the position of the nut in the flange. I was told that if overtightened this could lead to bad things for the transmission.
2) Remove the nut from the flange. I believe it is a 30mm.
3) Using a puller, remove the flange from the shaft.
4) Again, use a small screwdriver or similar tool to remove the seal.
5) Once removed clean the area of any debris, lightly oil the seal, and lightly push it into place. Using a seal driver or similar tool (read: sized socket) drive the seal into place.
6) Place the flange back on the shaft and lightly tap it into place. Screw the nut back on once the flange has slid on far enough. Tighten down nut. (I'm really not sure how much or far.)

Input Shaft Seal Replacement
1) Remove the release fork and the throwout bearing.
2) Remove the collar the t/o slides on. I believe they are allen head bolts.
3) Again, use a small screwdriver or similar tool to remove the seal.
4) Once removed clean the area of any debris, lightly oil the seal, and lightly push it into place. Using a seal driver or similar tool (read: sized socket) drive the seal into place.
5) Replace the collar.

Rear Main Crankshaft Seal Replacement
1) With the flywheel off, the seal with be exposed. Again, use a small screwdriver or similar tool to remove the seal.
2) Once removed clean the area of any debris, lightly oil the seal, and lightly push it into place. Using a seal driver or similar tool (read: brass rod or similar soft metal) drive the seal into place. I used a brass rod to lightly tap the seal into place once I had it set in.

Pilot Bearing Replacement
1) Using a small puller (jaws must fit in a 12mm ID) remove the bearing. This is easier said than done. The tool was available at the time for about $50. I chose to borrow it from a mechanic friend. Some have suggested packing the end of the crank with grease and then inserting a dowel into the center of the pilot bearing. Then tapping it in to push the bearing out. I'm not so certain it would work, but it might be worth a shot as a last ditch effort.
2) Using an appropriate press tool or equivalent (read: blunt end of a sized socket) tap the bearing into place.

Flywheel/Clutch Installation
1) Clean the friction surface on the flywheel.
2) Set the flywheel in place making sure the tdc notch is in the required position.
3) Place the plate onto the flywheel with the new bolts with a bit of the supplied loctite.
4) Torque the bolts down to the specified torque. A flywheel retainer should be used, but a pry bar or similar would work in a pinch.
5) Lightly grease the splines on the clutch disc
6) Set the clutch disk in place and align the pressure plate with the pins on the flywheel.
7) Insert the clutch alignment tool through the clutch and into the pilot bearing. I did not receive the tool with my clutch kit so there were a few options. Find the appropriate tool (available for about $10 at the time plus shipping), modify a similar clutch tool (I have been told that a Ford 5.0 clutch tool will work with some modification), or use a universal tool. I borrowed a universal tool.
8) Once everything is aligned, torque the pressure plate bolts down. UUC supplies standard bolts with lock washers.
9) Remove the clutch alignment tool and check to see that it is close.

Transmission Installation Preparation
1) If replacing the pivot pin, now is the time to do so. Tap out the old one and then place the new one back in. Same goes with the release fork spring.
2) Clean up the release fork and grease on all contact areas (throwout bearing contact, pivot contact, and slave contact) It should be obvious by the wear on the fork.
3) Reinstall the fork.
4) Slide the throwout over the input shaft and check to be sure it all slides smoothly.
5) Lightly grease the input shaft and it's all ready to go back in.
6) I hope I don't need to mention this, but don't forget to refill the transmission with ATF if you've drained it.

Transmission Installation
1) Secure the backing plate to the motor temporarily
2) Lift the transmission into place supporting it as you slide the input shaft through the clutch splines and into the pilot bearing.
3) Supporting the transmission, bolt the transmission to the motor. Be sure the backing plate is lined up correctly.
4) Begin tightening the bolts until the transmission is flush with the motor all the way around.
5) Torque all bolts to spec.
6) Install shifter by inserting end of carrier into foam locator and then aligning the front portion with the transmission. Then install the 'bitch clip.' It goes in much easier.
7) Insert shifter rod pin though joint and reinstall clip. Don't forget the two plastic washers.
8) Reinstall transmission support brace.

The rest of the procedure is just the reverse of removal.
Be sure to align the guibo with the arrows pointing towards the mounting point. Example, the arrow will point towards the flange on the output shaft.
The center bearing needs preloaded by pushing it forward approximately 4-6mm.

Update [03.06.04]:Well, I've not been 100% happy with this clutch/flywheel combination. It still rattled despite UUC's claim that the sprung hub clutch doesn't rattle. Well, I've changed thetransmission fluid from Redline D4 ATF to Redline MT-90 as per recommended by Rob Levinson at UUC. So far so good! I still have not gotten the correct pressure plate (I think I have the e28 M5 plate.) I'll work on getting one some day. The problem with I am having is a grinding when the clutch is fully depressed. So, what is it? Well, after pulling the tranny again, it's the release fork contacting the pressure plate! What a mess....

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