Driveshafts + UJ,s.???

[Big Dave]

Hi Chaps..
Im in need of a bit of advice...
944S2..

In preparing my car for the weekends track day,s , Ive found that one of the rear driveshaft gaitors was split wide open...[]
So knowing i had a pair of spare "slightly used" items [ supposedly only covered 35K off a turbo.] in the garage i set too + replaced the offending shaft.
No probs in getting the old one off the car[]. + fitted the "new" one on...[ After cleaning + repacking with CV joint grease...I also checked the joints on the replacement shaft for play + they seemed tight....ie no wear..]...

My dilema now seems to be, what feels like a wheel out of balance on the rear...A sort of "shimmy"..[&:][&:][&:][&:]
PS the wheel nuts are tight...[]

Are these shafts fitted on one way only ?? ie gearbox end or wheel end....or are they universal ,,ie fit either way round....??
I hope somebody can help me out ,, as time is running out ,, track day booked for Saturday AM + im travelling down on friday evening .. Blackpool to Bedford....

 

[Fen]

They can fit either way round for sure as swapping them is a quick fix to clicking. I can't really help with the imbalance to be honest, maybe Jon can offer some advice.

Did you use new bolts? If not they will come loose.

 

[dlknight]

Hi Dave,

Have you checked for any play in the drive shaft ? Just grab it in the centre with both wheels on the ground and try and rotate it back and forth. If you have any play then the bearings or races in the CV joint are shot. Also when fitting the new driveshaft back on did you put the spacer/washer plates on before putting the bolts on ? I read on rennlist (think it was rennlist) the other day that someone forgot the spacer/washer plates and was having a problem with the bolts binding with the hub.

Cheers

Dave K.

 

[Indi9xx]

If a driveshaft has spent its life on one side of the car, it will develop groves worn into the shaft more on one side of each internal channel than the other... then if you fit them to the other side of the car, they can in some cases cause a clicking noise or cause a form of vibration (even making it feel like the wheel has a buckle)

So its possible that the shaft had spent many miles to (for example) the nearside of a car, and if its now on the offside (for example) you may have some strange effects.

Any shaft can be mounted in any one of 4 ways on the car...

Say we call the 2 cv joints as A and B, they could be laid out in the following 4 ways.

A---B Trans X---X
B---A Trans X---X
X---X Trans A---B
X---X Trans B---A

In each one of those positions the cv's will wear differently. Put it in another position and it may play up...

On the other hand, its also a good idea to rotate (mount in another position) the shafts on a regular basis, as it will cause the shafts to wear reasonably evenly and last longer... although if you did this perfectly, you would also see all 4 cv's failing at the same time, so it would be more expensive in one hit.

 

[Indi9xx]

Of course, in my diagram, the X's are another 2 cv joints and where it says TRANS, thats the transmission, transaxle or gearbox, depending on what you want to call it

I could have labled the CV's as A, B, C and D for all 4 cv joints, but then I would have had to do diagrams for many more variations.

Does someone want to calculate how many variations there would be for the combinations of all 4 joints on two shafts being included in the CV shuffle?

 

[Fen]

I think I'm right in saying twice the combinations you have drawn: if you assume the X-X in the diagram is in every case C-D, then the only combinations not shown would be those with D-C, which would double the number.

 

[Indi9xx]

So for 4 cv joints there would be 16 combinations of position mounted to the car?

 

[Big Dave]

Hi Chaps..
Ta for the responses... Thats what these t,internet forums are all about..[][]..
Update on progress.
Slept on the idea last night + came up with the idea of removing the "wobbly" shaft + fitting the "other" spare one...
So i set too this am ,, 6-30am...[8|][8|] to be presise..
Only to find out the "other" spare shaft was nakered.[][][] one of the UJ, was defo worn out....Lots of clicking......Drove the car round all day today but it steadily got worse....[][]...SO,,
I set too this evening + changed the "good" uj,s from the wobbly shaft onto the "clicking" shaft...etc etc....
I do hope your keeping up here.....
I was about to put one of the good uj,s onto my split S2 shaft but found out there different [][], the splines didnt line up....[][]....

Now i find that all is well with the motor.. So it must have been the driveshaft was slightly bent... But you cant see it with the naked eye....

I was beginning to think that somebody had it in for me this week end.....[][][8|][8|][][]

 

[Andy Duncan]

The driveshaft repairs kits are about 65 quid +vat for each coupling kit, actually not bad if you can do the work yourself.

You get the grease, gaitor, coupling and gaitor straps. Given the high mileage 944's are racking up, if you intend to keep your car its not a bad investment in my opinion. Just a messy job. Rather than buying a 2nd hand set that may also be worn.

I noticed subtle changes between a set of 944S2 and Turbo S CV's, design of the splined centre part of the coupling was slightly different but I believe all parts are the same spec and therefore interchangeable.

andy duncan

 

[Hilux]

Did you use new bolts? If not they will come loose.

'kin `ell are you sure. I reused them once (Loctite 242) on offside on aborted attempt to change rear bearing and auto2000 swapped CV gaiter and re-used em before I did 150 down an autobahn. [&:][&:][&:]

 

[Andy Duncan]

I can assure you the driveshaft bolts loosen off. I wouldn't fit new ones all the time but I would check them regularly if you track the car.
andy

 

[Hilux]

I wouldn't fit new ones all the time but I would check them regularly

Another thing to add to my list []

 

[Fen]

I know of quite a few that have come adrift and all reused the bolts. I imagine they stretch to maintain torque and are not elastic enough to reuse.

 

[944Turbo]

Mine have done around 30K since last had them off, cleaned them well but reused them, I expect them to all fall out tommorow now,[]
Tony