cab 325i drive shaft rubber thing! HELP

[Taz]

hello guys my car was on ramp and i noticed a rubber doughnut thing between my gearbox and prop shaft......it is split and falling apart......is this difficult to change is it hard......wat do i need to do?

[Ant]

unbolt it and remove , simple really dude, you may need to drop the exhaust outa the way and drop the centre bearing to "shorten" the prop enough to remove it from the gearbox spigot

be aware thsoe bolts are tiiiiight !, undo them all with the prop in situ.

Have fun ! make sure and get a new one ASAP, avoid driving if its broken up , 'kin dangerous M8

~HTH

[jonbuoy]

I've not done this job but it look's pretty simple to do, just un bolt, pull the prop out the way, stick a new Donut bush in there and bolt the prop back up, Bob's your Uncle

[mrLEE30]

dont forget to pre-tension the centre bearing when you reassemble, preoceedure covered well in Bentley

[chu346]

dont forget to pre-tension the centre bearing when you reassemble, preoceedure covered well in Bentley

???

[gareth]

i didn't need to pretension...

make sure the bolts are torqued up properly though, mine were too loose thanks to a previous owner or mechanic and that allowed stress cycling and eventual fatigue of the bolts... to cut a long story short, it sheared two off and left the drive passing though one cracked bolt and the centre spigot! a mess and not recommended!

to get a torque wrench in there is a pain, jacking the car up as high as you can will help though.

[mrLEE30]

Bentley proceedure mentions sliding the centre bearing a couple of mm either forward or rearward then tightening it up. i dont have it with me but it is definately mentioned.

i will check.

mrlee

[gareth]

oh yeah... sorry i was being stoopid! forgot about that bit!

[Brianmoooore]

Bentley proceedure mentions sliding the centre bearing a couple of mm either forward or rearward then tightening it up. i dont have it with me but it is definately mentioned.

i will check.

mrlee

Even Haynes gets this bit right.

[Brianmoooore]

I've not done this job but it look's pretty simple to do, just un bolt, pull the prop out the way, stick a new Donut bush in there and bolt the prop back up, Bob's your Uncle

Not quite this simple as the prop has a spigot on the end that locates into the gearbox output flange.
Prop has to be shortened by about 20mm to get this apart, either by the sliding splines in the middle, or by dropping the centre bearing.

[mrLEE30]

to confirm....prop shaft reassemble method

1. position prop shaft at rear diff, centre bearing then loose on the mountings
2. tighten rear coupling with new lock nuts to 72Nm
3. reconnect flex coupling/prop to transmission torque M10 grade 8.8 to 46Nm, M10 grade 10.9 to 72Nm, M12 to 123Nm (with new lock nuts)
4. slide centre bearing forward toward gearbox/UV joint from its unstressed position 4-6mm, then tighten fixings to 22Nm
5. tourque the clamping sleeve on the splined prop coupling to 17Nm


DONT forget when you disasseble the prop to mark it before you undo anything i.e between prop and diff, between prop small and prop large, between prop and dounut, and donut and tramsission output shaft.

it should all go back in same manner (unless you replace the donut)

failure to do so will equal (cue the music) bad bad bad .... bad vibrations


bobs your uncle.

mrlee

[Taz]

got it sorted straight away!.......got a mechanic to do it he charged 30quid......i couldnt jack my car high enough to get under it.......but many thanx to all who replied.......the info was most helpfull......the mechanic was a bit of a nob.....so i told him wat u guys advised me to do!!

may all your e30's hav a long happy life!

[gareth]

Ԛ£30 is cheap.

what was it?

for that little, it could be broken prop donut bolts like i had? if so, did he replace all of them?