Driveshaft issues + gearbox removal pics

[Federico]

I'm getting ready to drop my transmission for a clutch/seal service, and I've just removed the driveshaft. At first glance, it seems like the CSB is mounted the wrong way around.
Also, the clocking of both shaft halves looks odd. Is it me, or are they 90° off?

[jayjaya29]

The CSB is mounted correctly.

Did you place the red marks on the shaft?

[Federico]

The CSB is mounted correctly.

Did you place the red marks on the shaft?

Those are my marks; did them before dropping the shaft in case it came apart while doing so. I can't see any older marks.

[jayjaya29]

As long as you didn't have any strange vibrations before dropping it I wouldn't touch it.

[Federico]

As long as you didn't have any strange vibrations before dropping it I wouldn't touch it.

My driveshaft did shudder somewhat when moving off in 1st gear. Having researched the manuals and consulted with a driveline rebuild shop, I have confirmed that the splined joint was mounted 90 degrees off. Some hack had replaced the CSB and messed up the clocking.
BTW, the CSB is also mounted incorrectly. I'll put a new one in, with the open end facing forward, so that I can actually preload it.

As a side note, one of the u-joints had a very tiny amount of play, and the machinist said it was not worth messing around with repacing it.
He said something like "I don't want to take your money for a job that's not needed; bring the shaft back when it's really f*cked, then we'll handle it"
So that's a plus
He also didn't like the GKN u-joints I supplied, stating that the sheet metal caps will conform to the bore they are pressed into, and if the latter wasn't perfect it would cause issues. He prefers to use joints with machined caps when rebuilding BMW shafts.
He's been doing this since the sixties (his son does most of the work now), so I guess he knows his shit

[1st 5er]

Sounds like he knows his too.

[Mike W.]

As a side note, one of the u-joints had a very tiny amount of play, and the machinist said it was not worth messing around with repacing it.

My experience is the U joints get stiff and notchy, not loose. But unlike most places which run the other way at the very mention of a BMW driveshaft, it sounds like he's been there.

[Federico]

Spent the last cuple of days removing the G265.
The clutch doesn't look as bad as I expected; a new sachs unit will go in its place.
As for the rear main seal, it appears to have stopped doing the sealing thing:















These new parts will go in

Rear main seal
pilot bearing
clutch kit
fork pivot & spring
flywheel bolts
clutch plate bolts
3x Transmission seals
trans mounts

Old driveshaft will be reinstalled correctly, with new guibo, CSB, centering bushing, and the rubber insert for the coupling sleeve, which has turned into goop.
I'll try to have a machinist refurbish the shifter bushings; It'll probably be nicer and cheaper than buying the new parts.

[Aldo525]

Hola Federico,

Not sure if your concern is about the original position of the U joint on the driveshaft but here is a picture of a new one I bought last year in Germany for my e28 525ia....maybe the picture clarifies your doubt.

Greetings,
Aldo

[Federico]

Hola Federico,

Not sure if your concern is about the original position of the U joint on the driveshaft but here is a picture of a new one I bought last year in Germany for my e28 525ia....maybe the picture clarifies your doubt.

Greetings,
Aldo

Thanks for the pics. I've confirmed that my driveshaft was separated and joined back together incorrectly. The cap at the rear end of the long tube should be on the same plane as the one near the bearing. You can tell in my pics that this is 90° off. I'll line them up correctly, and worst case scenario I'll have to separate the shaft again and rotate 180°. One of the 2 positions is how it was balanced by the factory.

[Aldo525]

Hola Federico,

Not sure if your concern is about the original position of the U joint on the driveshaft but here is a picture of a new one I bought last year in Germany for my e28 525ia....maybe the picture clarifies your doubt.

Greetings,
Aldo

Thanks for the pics. I've confirmed that my driveshaft was separated and joined back together incorrectly. The cap at the rear end of the long tube should be on the same plane as the one near the bearing. You can tell in my pics that this is 90° off. I'll line them up correctly, and worst case scenario I'll have to separate the shaft again and rotate 180°. One of the 2 positions is how it was balanced by the factory.

I'll check the old driveshaft for any recognizable position marks. It must have had something from the factory to avoid assembly errors, perhaps some very small marks. I'll let you know what I find later.

[Federico]

I'll check the old driveshaft for any recognizable position marks. It must have had something from the factory to avoid assembly errors, perhaps some very small marks. I'll let you know what I find later.

I couldn't find any marks, but sure, any help is appreciated

[Ju@n]

There must be some place you can take the driveshaft to have it balanced, it's not a terribly complicated procedure (and it's not horribly expensive either). I had mine balanced although had the same issue around changing u-joints, the place that worked on driveshafts didn't have the machine to remove this ones, and it wasn't in too much of a bad shape.
Now when I leave my car alone for a couple months, at the very beginning of the drive (at about 60km/h) you can feel a small shudder, it goes away a couple mins after driving and is only there at 60. My guess is that it's the u-joints
I changed the center driveshaft bearing but not the rubber mount itself since it was ok.

[Aldo525]

I'll check the old driveshaft for any recognizable position marks. It must have had something from the factory to avoid assembly errors, perhaps some very small marks. I'll let you know what I find later.

I couldn't find any marks, but sure, any help is appreciated

Federico,

Checked my old driveshaft and one side (long rear) is clearly marked with a faded red dot....unfortunately the other side (short front) is completely rusted by all the years near the exhaust piping so no red dot mark visible...

Can't see any other marks on the steel, I presume fabricators used paint to mark the position, if they did it.

[Federico]

Just posting a final update on this job. The car has been running for a couple weeks now and the diveshaft seems to be working just fine.
The shuddering I felt when pulling away is gone and it also feels smoother when cruising down the highway. Here's some pics:



The rear main seal carrier set me back a few days. One of the threads for the oil pan was stripped so I had a machine shop put inserts in both threads.
I'm glad I didn't try to do this at home: after the job, the machinist told me the magnesium felt very brittle, and it chattered and fought him all the way in:



When installing the Sachs clutch kit, I found the alignment pin to be too thick for the pilot bearing. I ended up buying a universal tool which seemed flimsy at first glance but actually worked perfectly fine. It clamps the disc to the pressure plate and one must align their outer edges before tightening it (it's not a precision tool, just a clamp). The transmission slid right in.





Driveshaft was put back together with the joints aligned and a new febi CSB. The febi part didn't feel as stout as the OE one I removed, but felt fine after mounting and preloading it; we'll see how long it lasts.



I also got a new febi clamping sleeve with its rubber insert, but ended up reusing the original sleeve with was much stronger. The febi was also missing the washer that goes inside. My original rubber insert had rotten and made the driveshaft "click" when coming on and off the throttle. No noise now.



Transmission was reinstalled, bellhousing first and then the tranny itself. I never removed the exhaust so it took a little bit of maneuvering with a helper operating the jack, but it can be done. Tranny has to go up diagonally tail up over the exhaust, then pushed back and up until the input shaft clears the bellhousing, and then lifted to be level with the engine.
As per the BMW manual, the slave was installed temporarily to keep the throwout bearing centered while inserting the gearbox.











Afterwards, I had some issues bleeding the clutch. Since the slave was a few months old I removed the master and found lots of gunk around the piston. I did have an "autofren" brand seal kit in my parts stash, but the rear seal was just wrong for the application. Also, the joint where the rod connects to the piston was quite beat up and I was worried it would detach. A new Sachs master went in and problem solved.

[Ju@n]

Great job!
I hope someday I can go over to Argentina in the e28 Where are you located? Buenos aires?

[Federico]

Great job!
I hope someday I can go over to Argentina in the e28 Where are you located? Buenos aires?

Yes, I'm close to Buenos Aires. With the shortage of tires we're having now, I may end up driving to Uruguay to buy a set. Did that trip several times but not yet with the E28.

[Ju@n]

Great job!
I hope someday I can go over to Argentina in the e28 Where are you located? Buenos aires?

Yes, I'm close to Buenos Aires. With the shortage of tires we're having now, I may end up driving to Uruguay to buy a set. Did that trip several times but not yet with the E28.

Makes sense, I've seen quite a few argentinians driving over. Congrats on the world cup!