Any Clutch Tips

[brianwolf3]

Hello everyone im getting ready to change out the clutch on my 89 bmw 525 this weekend. Is there any tips out there that could help me go through this smoothly? Is there anything different about these cars than others. Any help will be appreciated.

[gale]

Pretty basic. If you've done a clutch on a rear wheel drive car/truck before, it's all intuitive. Do a good visual inspection of the flywheel surface if it's a dual mass & look for hairline cracks. If it's reusable, you can lightly sand the surface with a jitterbug with the "Jon K" treatment.

1. put all 4 corners up on jackstands
2. remove the exhaust
3. remove the alumunum heat shield
4. support the trans & remove the crossmember
5. unbolt the front of the driveshaft at the quibo. Temporarily remove the 2 center bearing bolts to flex the driveshaft enough to disengage the front of the driveshaft from the center stub at the end of the trans output yoke. Re-attach the center bearing bolts to the chassis & swing
the front half of the driveshaft to the side & tie it out of the way
6. lower the trans slightly (make sure the fan clears the radiator, remove the fan if necessary, make sure there's clearance for the head against the firewall
7. undo the clips on the shift lever link rod & remove
8. lower the trans enough to get room to reach the top bell housing bolts (see #6). With e32 & e34 m30's the engine will rest nicely on the swaybar. Use about 30"-36" of socket extensions & a mirror & flashlight to get to all of them. It's good to have a helper turn the wrench while you keep the socket on the bolt.
9. remove the trans. Be careful that it separates straight out without bending/stressing the input shaft. Note that there are 2 sleeves that act like alignment dowels on either side (the 2 larger hex head bolts). Make sure they're there when putting it back together.
10. remove the pressure plate & disk
11. If removing the flywheel, One of bolts also has an alignment sleeve, make sure it goes back in.
12. The pilot bearing comes out by hammering soft bread or playdough thru the center hole with a wooden dowel & hammer. Make sure you put a new pilot bearing in. The newer style pilot bearing is sealed and if so, you can discard the metal & felt washers.
13. good time to replace the rear main seal
14. ditto for the trans input shaft seal
15. the throw-out bearing simply pulls off. Most of the new replacement throw-out bearings are plastic & don't use any grease at the throw-out fork. There was discussion about this about a month ago.
16. undo the spring clip that holds the throw-out fork
17. be sure to replace the plastic pivot dammit that the throw-out fork registers on
18. there is a tiny seal on the shift shaft that usually leaks. It's kind of a pain to remove. I ground the tip of a small disposable screwdriver to hook it from inside the lip of the seal and pull it out. Be careful not to scratch the shaft:

http://www.nmia.com/~dgnrg/tool02.jpg

[Dave M]

Wow, nice write up Gale!

[gale]

One more thing I forgot to add: the guibo has 6 arrows molded into the rubber around the perimeter, 3 point to one side and 3 point to the other. The arrows point to the respective "ears" of the trans & driveshaft yokes that it bolts to. If it's clocked one hole off, the new one won't last very long. When installing, put a wrench on the bolt heads & turn the nuts to tighten, not the bolts, otherwise it can tear out the metal sleeves.



Thanks. I'm up to my ears in transmission jobs lately so all of this is very fresh -- in fact my son & I were in the final stages of putting his back in just last night:

1. A-clutch pack repair on son's 89 535i 4hp22 -- almost finished, we'll road-test it tomorrow.

next:
2. Swap trannies on wife's 93 e36 325ic -- 2nd & 5th syncro's are shot so bought another good used trans.
3. e9 flywheel for my 7 & try out the spare Getrag 260/6 -- will eventually do a 5-spd conversion on my son's e34 & give him my "hand-me-down" parts
4. install 3.73 LSD in my 7 -- finally decided the 3.91 is too high for a daily driver. I'll put the spare 3.64 in my son's e34 if we ever get around to doing the conversion.

[DanDombrowski]

Will you be my Dad?