engine and drivetrain driveshaft alignment procedure

[Redtail]

Hey Guys, I have a '73 with a 5-speed transmission swapped in and I just replaced the guibo and now I have some pretty bad driveshaft vibrations.  I didn't really do anything special to try and align things and apparently that is far from good enough.

 

So is there an article or step-by-step procedure around explaining how to go about getting everything aligned? I have the Chilton manual but it's basically no help at all.

 

Many thanks,

Zack

[Simeon]

Just to clarify: this is a pre-existing 5 speed swap which had no vibration issues prior to replacing the guibo?

No work done to the driveshaft which saw it split?

Did you preload by adjusting the diff position/ centre bearing?

Take the steel band off the new guibo?

What was the rear transmission mount like?

[Simeon]

Here is an excellent post on the subject found with the excellent search tool.

http://www.bmw2002faq.com/topic/76123-guibo-failure/

Another good one from this post is the presence / condition of the drive shaft centre alignment nipple / bearing doohickey?

[jimk]

Front section of driveshaft may be aligned correctly, but vibration comes from the u-joints angles out of agreement.

[Redtail]

Just to clarify: this is a pre-existing 5 speed swap which had no vibration issues prior to replacing the guibo?

Yes

 

No work done to the driveshaft which saw it split?

Correct it was not split

Did you preload by adjusting the diff position/ centre bearing?

Yes I preloaded it by moving the center bearing forward by the specified amount

I did not touch the diff at all

 

Take the steel band off the new guibo?

It has the 6-bolt guibo that did not have the steel band

What was the rear transmission mount like?

I put a new HD rubber mount (320i I believe) in when I replaced the guibo

Edited September 23, 2015 by Redtail

[Redtail]

Here is an excellent post on the subject found with the excellent search tool.

http://www.bmw2002faq.com/topic/76123-guibo-failure/

Another good one from this post is the presence / condition of the drive shaft centre alignment nipple / bearing doohickey?

 Thanks for the link, I will read through and double check my work. 

 

The bearing/bushing that is inside the driveshaft and centers it on the output shaft of the transmission is present and seems to be in OK condition, though I did not replace it.

 

Does anyone actually align their driveshaft with the fancy 4' long stick tool or is that not really necessary?

 

Thanks again for all the advice guys

[tzei]

Ok so here is mine...

 

Tight fit pieces to diff case & CrMo tube (true) - shows me where pinion points. Parts made for Typ168 and Typ188 diffs.

True bar that has hollow point to fit g.box tail guide pin. Lathed ring in a new c.bearing. This slides over the bar (bearing location and/or g.box lenght can be altered).

 

Have served me well.

[M3M3]

Does anyone actually align their driveshaft with the fancy 4' long stick tool or is that not really necessary?

 

completely unnecessary.   the only part of the alignment you care about is getting the front of the DS square on the quibo.  anything aft of that is irrelevant.  

[Redtail]

completely unnecessary.   the only part of the alignment you care about is getting the front of the DS square on the quibo.  anything aft of that is irrelevant.  

 

This is awesome advice, thanks so much Mlytle. I've been looking at drawings and thinking about welding one up but figured I'd do some more research first.

 

I'm going to follow all the tips in this thread and try another alignment this afternoon, will report back with any progress.

[jimk]

the only part of the alignment you care about is getting the front of the DS square on the quibo. anything aft of that is irrelevant.

Disagree.  Some education on u-joint alignment is due.

Aligning mine (an original owner, non damaged car) got rid of the rumble.  U-joint alignment on 02s can be out, the rear subframe can be whacky.

[M3M3]

and...disagree(sort of) right back at ya! 

 

the front of the driveshaft MUST be aligned with the output shaft of the tranny.  period.  the guibo cannot be out of line.  period.

 

after that is done, the front of the driveshaft may not line up with the rest of it.  only way to fix this is to muck with the not very adustable engine and tranny mounts.  the couple of degrees of misalignment is perfectly acceptable.  this is assuming you have a good driveshaft with u-joint in tight working condition.  yes, you don't want the angles to be radically different (per your diagram).

 

the u-joints are there to accommodate the driveshaft not being perfectly straight.  in fact, there is a viewpoint that the u-joints should not be perfectly straight to prevent wear in just one spot.

 

I have a very noticeable kink in the driveshaft at the center bearing and the diff.  zero issues.  and this is with a driveshaft that is spinning WAY beyond design spec (9k+rpm) with an OD tranny and 4.44 diff at 120+ mph. 

 

heck, the two driveshafts in my 4wd truck (that each have two u-joints) have relatively huge angles in them.  no issues.  that is what u-joints are for.  they do not need to be perfectly aligned.  those fancy alignment sticks for 02's are pointless.  they won't help the angle difference issue you highlighted Jim.

 

JMHO, of course!

Edited September 24, 2015 by mlytle

[kid2002]

I went with Mlytles theory. I'm using an E30 driveline and engine though.. Interesting to see everyone's opinions on the subject.

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[jimk]

I think the alignment of u-joints was completely missed.  Angles of each is not important, but both the first and second need to be as near the same as possible.

My statements are not opinion.  My reference is my college textbook Mechanism and Dynamics of Machinery.  I pulled it off the reference shelf because I don't publish bs.  If I can't back it up, I will be silent.  Additionally there was a study problem in class to show by mathematical proof that the intermediate shaft angular velocity oscillates.  If anyone wants the algorithm I can provide.

I also learned to do it right years before going to college from truck line repair. 

It isn't necessary to muck with the engine mounts to line it up.  A good machinist will adjust the diff angle setting!  Why bust your knuckles if not necessary.

I didn't say anything about the "sticks", they don't  anything to fix a rumble. Angle finders are used after the first section of the driveshaft is aligned to the transmission.

A close look at the diff, the pinion shaft is not parallel to the mounting base surface it points up at the same angle as the engine slopes down.  Get them out of parallel, rumble is generated.

Kiss it off if you guys want, but the correct way is to have the dif input shaft on the same plane as the front section of the driveshaft.

BTW the common name U-joint is really a Hooke's Coupling.

Too much plug and play and follow the next guy on this board.

Edited September 24, 2015 by jimk

[Redtail]

Uhhh well okay, I got the bad vibration fixed.

 

I spent a couple hours with a box of washers under the car shimming and adjusting the transmission mounts and the center bearing mount until the guibo was aligned with the output flange as described above. This fixed my vibration issue. I did not get any deeper into it than that but I will look into it again (according to jimk's tips) if need be.

 

One thing to note is that my tranny mount is on full stop to the driver's side and the center bearing mount is on full stop to passenger's side. Not sure if that's an issue with the 5-speed swap (PO welded in new mounts) or if the engine mounts are worn or some other issue. Either way it is working great now and I appreciate all the advice.

 

Cheers

[kid2002]

Glad to hear you go it sorted out, at least for the time being. Now, enjoy driving it and don't worry about it being "perfect". If you're happy with how it drives that should be good enough. Nothing lasts forever. Tell that to my suspension and wheel specialist..

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